Dissertations / Theses: 'Sensory analysis of food'

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Di, Donfrancesco Brizio. "Sensory analysis and acceptability of pet food." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/34524.

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Doctor of Philosophy
Department of Food, Nutrition, Dietetics, and Health
Kadri Koppel
The pet food industry represents a competitive and growing part of the food industry that is constantly looking for innovation to differentiate products in the market. In recent years, the pet food market has undergone a humanization trend that has transformed pet owners into parents. In the light of this trend, pet owner acceptance has become even more crucial to product developers as the owners are the ones who make purchasing decisions. Performing descriptive sensory analysis on pet foods utilizing a human panel can assist in understanding the sensory characteristic of products. Knowing the sensory profile of pet food can then be useful in product development, in order to relate the descriptive data with palatability data from pets and to understand specific sensory attributes that drive pet liking. At the same time descriptive analysis can help understand what drives consumer acceptance of the products. The first objective of the research was to develop a sensory lexicon that could assist researchers and sensory professionals working in the pet food industry to describe appearance, aroma, flavor, and texture characteristics of dry dog food. More than seventy sensory terms were identified, defined, and referenced. The second objective was to utilize this sensory lexicon to understand relationships between sensory properties of products and pet owners’ liking. Results indicated that appearance played a major role in driving consumer liking of dry pet food. The next objective of the research was to understand sensory qualities and acceptance of extruded dry dog food manufactured with different fractions of red sorghum through some of the developed concepts. Sorghum is an important crop to Kansas that represents the first producer in USA. Sorghum characteristics such as a low glycemic index and antioxidant properties make it a perfect fit for pet food industry. A process such as extrusion may then help improve some negative characteristics such a lower digestibility that has been associated with sorghum in the past. Descriptive sensory analysis was performed and results indicated that aroma and flavor profile of the sorghum diets were not dissimilar to the ones of a control diet manufactured with rice, wheat, and corn, grains that are typically used by the pet food industry. Acceptance of pet owners was then assessed through a Central Location Test involving 105 consumers. The whole sorghum diet resulted to be the most liked sample by consumers, at the same level of the control diet. The next objective was then to understand how the experimental diets would be accepted by pets compared in a home situation. Thirty dogs were fed the diets in their own household environment over 20 consecutive days. No differences in acceptance for the diets were found. The last portion of the research was to determine volatile compounds present in the four diets and try to identify possible relationship with the sensory properties of the samples. Thirty-six compounds were identified with aldehydes being the most abundant volatiles group. Several relationships with sensory characteristics of samples were found.

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Bisschop, Sean M. "Food sounds, sensory, acoustic, and mechanical analysis of two snack foods." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq24445.pdf.

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Deans, Gillian A. "Design and analysis of sensory evaluation experiments." Thesis, University of Newcastle Upon Tyne, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240734.

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Liu, Yu-Hui. "Multivariate methods for relating different sets of variables with applications in food research." Thesis, University of Bristol, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303768.

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Pairin, Hongsoongnern. "Understanding the sensory characteristics of fresh and processed tomatoes using descriptive sensory analysis." Diss., Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/261.

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CAMARGO, RITA J. de. "Estudo do tratamento combinado de radiacao ionizante e cobertura de quitosana em mamao papaia (Carica papaya L.)." reponame:Repositório Institucional do IPEN, 2004. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11250.

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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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Kuhlman, Nicholas Grant. "Sensory and Instrumental Analysis of Pasteurized Dill Pickles Made from Acidified, Bulk Stored Cucumbers." NCSU, 2009. http://www.lib.ncsu.edu/theses/available/etd-07092009-110919/.

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Storing fresh cucumbers for an 8 to 12 week period in an acidified, non-fermented environment prior to processing would extend the time for processing locally grown cucumbers into pasteurized pickle products. The effect of acidified storage of fresh cucumbers for up to 120 days prior to their conversion to pasteurized dill pickles was evaluated. Cucumbers stored at 18ÂºC prior to pasteurization maintained a fresh, non-cured appearance as well as a firm texture. Equilibrated acid concentrations of 3.5% acetic acid also helped to reduce the amount of curing and maintained firmness in cucumber tissue. Dill pickles made from acidified, bulk stored cucumbers maintained a firm texture after pasteurization. However, the cured appearance of bulk stored cucumbers increased by 40% within 30 days of pasteurization so that it was much higher than the cured appearance of dill pickles made directly from the same lot of fresh cucumbers and stored for an equivalent period of time after pasteurization. Sour, sweet, bitter and vinegar intensities were similar for dill pickles prepared from either bulk stored or fresh cucumbers. Firmness, saltiness, and dill flavor while significantly different, differed by less than 1 point on a 15-point scale. The major flavor difference between pasteurized dill pickles made from stored acidified cucumbers and pickles made directly from fresh cucumbers is that pickles made from stored cucumbers had an âotherâ flavor. The intensity of this flavor was perceived at a similar level regardless of the brine composition or storage time of the cucumbers prior to pasteurization. Descriptors for this âotherâ flavor were chlorine, pool, barny and metallic. GCxGC-TOFMS analysis of volatile components in dill pickles prepared from bulk stored cucumbers and dill pickles prepared from fresh cucumbers resulted in detection of 24 components that were significantly different (p<0.05) between at least one treatment pair. Individual volatile components did not provide a clear basis for differentiation among different storage brine treatments. However, PCA analysis using the 24 components was able to differentiate treatments.

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Almeida, Susana Cristina Aleixo de. "Emotional responses elicited by wine when pairing with high fat food." Master's thesis, ISA, 2017. http://hdl.handle.net/10400.5/14827.

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Mestrado em Viticultura e Enologia / Instituto Superior de Agronomia / Faculdade de Ciências. Universidade do Porto
This work was aimed at the evaluation of emotional responses elicited by wine before and after food consumption. The tastings were performed by one trained panel and by consumers, segmented by gender, Vinotype, 6-n-propylthiouracil (PROP) sensitivity and Saliva flow rate. Three commercial red wines with different sensory features were used: i) Grand Gold awarded wine from Alentejo (2013); ii) wine from altitude vineyards in Douro (2011), iii) classical European old wine (1999) from Bairrada. Wines were evaluated using a tasting sheet with emotional and conventional tasting descriptors before and after eating a typical Portuguese dish, whose distinctive feature was its high fat content. Overall, food did not change the global evaluation scores given to the wines but some of their characteristics were scored significantly different through the emotional tasting. The results of both panels demonstrated that the emotional responses were more correlated with the global evaluation of the wines than the classical sensory descriptors. Within the trained individuals, the main correlations with global evaluation were obtained with “Initial Impression”, “Expectation for the mouth” and “Impression in relation to odor”. In particular, the global evaluation for the Bairrada wine, could be predicted by a model including these three variables with a R2=0.73. With the untrained tasters, the correlation with global evaluation was only significant for the “Impression in relation to odor”. The average scores given to the three wines by both panels did not diverge, despite their different sensory attributes. Therefore, our work only reflected trends in wine preferences. The untrained panel preferred the Alentejo wine while the trained panel preferred the Douro wine, before the food ingestion. The correlations between the global evaluation and the other sensory descriptors for the Alentejo wine could not explain this preference. We speculate that the untrained panel scored the wines based on what they are used to drink, giving lower scores to the unfamiliar one. The trained panel demonstrated a higher correlation between emotional and sensory descriptors. In fact, the trained panel seemed to understand better the different range of qualities of the wines. After ingesting food, the preference changed only for the trained panel, showing preference to the Bairrada wine. Both panels agreed that the old Bairrada was the most complex and difficult wine to understand In conclusion, the emotional tasting sheet was easy to interpret by all segments of consumers, leading to open and fair answers because it appeals to individual personal feelings. This tasting approach appears to be promising in the rapid learning of the different wine styles. In the future, it would be interesting to evaluate the evolution of scores given to unfamiliar wines that would require time to be appreciated using appropriate foods. This way, the classical European wines, that are difficult to understand by consumers, would have a better chance to be correctly appreciated
N/A

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Dooley, Lauren. "Lexicon development for lip products using descriptive sensory analysis." Thesis, Manhattan, Kan. : Kansas State University, 2007. http://hdl.handle.net/2097/501.

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Van, Eeden Petrus Rabe. "Chemical, sensory and consumer analysis of cork taint in South African wines." Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/2092.

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Thesis (MSc Food Sc (Food Science))--University of Stellenbosch, 2009.
This study focused on a serious quality-related problem in the global wine industry, including the South African Wine Industry, namely cork taint in wine. Annually, large financial losses are incurred by cork suppliers and wine producers, as a result of cork-tainted wine. Although contaminated new unused corks are frequently implicated as the origin of this taint, contaminated cellar equipment and water can also be the source of the problem. An explorative investigation into the incidence of cork taint in South African wines showed that 3.8% of the 133 wines tested, contained 2,4,6-trichloroanisole (TCA) concentrations of 3.5 ng/L and higher, as determined by gas chromatography coupled with electron capture detection (GC-ECD). TCA concentrations higher than 1 ng/L were found in 18% of the wines tested. All affected wines were sealed with solid or agglomerate cork stoppers. These wines were sourced from various wineries in the Western Cape region, South Africa and were of different cultivars. None of the wines sealed with synthetic closures had any detectable TCA, 2,4,6-tribromoanisole (TBA) or pentachloroanisole (PCA) levels and only very low 2,3,4,6- tetrachloroanisole (TeCA) levels (1 ng/L or less). Another group of 28 wines that were rejected by the official South African wine regulatory body on the basis of the presence of mouldy taint during wine certification, was also included in this study. GC-ECD analysis showed that 30% of the wines in this group contained TCA at concentrations of 3.5 ng/L and higher. These results pointed to a relative high incidence of TCA in the wines investigated, especially those sealed with cork stoppers. Although no general conclusions should be made on the incidence of cork taint in the wider wine industry based on the results found within this explorative investigation, these findings confirmed the presence of cork taint in South African wines. Detection threshold values were determined for TCA, TeCA, TBA and PCA in three wine cultivars using the standard ASTM method. Results indicate that factors relating to the wine cultivar seemed to affect threshold values considerably. Our research proposes a detection range rather than an average detection threshold. Detection ranges established for TCA, TeCA, TBA and PCA in Chenin blanc, Pinotage and Shiraz coincide with reported values in literature. This result can be regarded as a valuable expansion of the existing knowledge of detection threshold values. Descriptive sensory analysis indicated significant (P 0.05) changes in the aroma profile of Chenin blanc, Pinotage and Shiraz after TCA, TeCA, TBA or PCA was added to the respective base wines that contained no detectable levels of the haloanisoles. The mouldy taint induced by these haloanisoles were described as mouldy, mouldy-chemical, mouldychlorine, as well as mouldy-acidic. In Chenin blanc, additions of TCA, in the concentration range 1 to 17 ng/L, resulted in a marked increase in the mouldy aroma and was accompanied by an immediate decrease in fruitiness. This change was already evident at added TCA concentrations of 1 ng/L. Similar trends were observed in Pinotage, while the addition of low levels of TCA to Shiraz (2 ng/L) resulted in a significant (P 0.05) decrease in the herbaceous character of the wine. The aroma changes observed were prominent enough to render the wine totally unacceptable in comparison to its original character. Consumers’ degree of liking did not seem to be affected by very low concentration levels of TCA in Chenin blanc, Pinotage or Shiraz, but rejection increased as the concentration increased beyond detection threshold level. A slight gender effect was also noticed. Female consumers appeared to be more sensitive to increasing levels of TCA, whereas male consumers did not respond as negatively to higher concentration levels of TCA. This study makes an important contribution towards understanding the sensory impact of especially TCA contamination in wine, through the establishment of concentration ranges at which these compounds exert a noticeable detrimental effect on the aroma profile of wine. Additional insight into cork taint in wine is provided by the consumer preference studies, where the effects of the taint on the product acceptance by consumers are demonstrated. The development of a modus operandi to ensure that sensory panels provide reliable data, can be regarded as an important contribution to wine-related research. This study is one of the first where advanced sensometric techniques were applied in sensory studies on cork tainted wines.

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Koch, Ilona Sabine. "Development of a sensory lexicon and sensory wheel for rooibos (Aspalathus linearis) and the role of its phenolic composition on taste and mouthfeel." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6569.

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Thesis (MSc Food Sc)--University of Stellenbosch, 2011.
ENGLISH ABSTRACT: The sensory characteristics and chemical composition of rooibos infusions were analysed to establish the extent of variation in sensory attributes and compositional parameters, and investigate whether correlations exist between the sensory characteristics and the phenolic composition. To capture as much potential variation as possible, 69 rooibos samples were collected throughout the 2009 harvesting season from different production areas. The samples were also representative of the different quality grades (A, B, C or D) which are based on the appearance of the leaves, and the colour and flavour of the infusion. Quantitative descriptive analysis was used to develop sensory profiles for each of the rooibos infusions. Considerable variation in the sensory characteristics was observed, highlighting the need for standardised terminology that can be used to describe what is often referred to as “characteristic” rooibos flavour. Aroma, flavour, taste, and mouthfeel descriptors were generated and assembled into a rooibos sensory wheel. The most recurring attributes were selected to compile a rooibos sensory lexicon which provides a definition and a reference standard for clarification of each term. A combination of “honey”, “woody” and “fynbos-floral” notes with a slightly sweet taste and subtle astringency may be regarded as “characteristic” rooibos attributes indicative of good quality tea. Pleasant “caramel” and “fruity-sweet” notes were also observed in a number of infusions, whereas negative descriptors, associated with poor quality rooibos, included “green” and “hay” flavours. Large variation in the composition of rooibos infusions was revealed through the quantification of soluble solids (SS), total polyphenols (TP), tannins and 14 monomeric phenolic compounds, as well as spectrophotometric colour measurements. High quality rooibos was associated with higher levels of SS, TP, tannins and phenolic compounds than low quality rooibos. Correlations between the compositional parameters and sensory attributes of the infusions indicated that several non-volatile compounds, including enolphenylpyruvic acid-2-glucoside, quercetin-3-glucoside, and iso-orientin, were associated with the characteristic sweet taste of rooibos, while bitterness was related to certain flavonoids such as luteolin, quercetin and aspalathin. The only compound significantly correlated to astringency was rutin, although it is likely that aspalathin and several other monomeric flavonoids also contribute to astringency. The tannin content was not associated with astringency possibly because of the limitations associated with the tannin quantification method. To determine whether compositional changes resulting from steam pasteurisation of rooibos leaves influence the sensory quality of rooibos infusions, differences in the phenolic composition and sensory attributes of infusions, prepared from unpasteurised and pasteurised rooibos, were analysed. Steam pasteurisation significantly reduced the SS, TP and aspalathin content of rooibos infusions, as well as the absorbance, especially at a wavelength of 450 nm. It also resulted in significant reductions in the intensities of most of the aroma and flavour attributes, especially the “green” notes associated with low quality rooibos. After steam pasteurisation the prominent “green” flavour of certain samples was frequently replaced by a “hay” flavour. The taste attributes, sweetness and bitterness, remained unchanged, whereas the astringency of rooibos infusions decreased significantly.
AFRIKAANSE OPSOMMING: Die sensoriese eienskappe en chemiese samestelling van rooibostee is geanaliseer ten einde die mate van variasie van die sensoriese sowel as die chemiese profiel te bepaal, asook om vas te stel of korrelasies bestaan tussen die sensoriese eienskappe en die fenoliese samestelling van rooibostee. Om soveel as moontlik potensiële variasie in te sluit, is 69 rooibos monsters tydens die 2009 oesseisoen van verskillende produksiegebiede versamel. Die monsters is ook verteenwoordigend van die verskillende kwaliteitgrade (A, B, C en D), wat op grond van die voorkoms van die teeblare, en die kleur en geur van die tee toegeken is. Kwantitatiewe beskrywende analise is gebruik om ‘n sensoriese profiel vir elke rooibostee op te stel. Aansienlike variasie in die sensoriese eienskappe is waargeneem. Dit het die behoefte aan gestandaardiseerde terminologie onderskryf, wat gebruik kan word om die term “karakteristieke” rooibos geur in meer detail te omskryf. Spesifieke terme vir aroma, geur, smaak en mondgevoel is geformuleer, en gebruik om ‘n sensoriese wiel vir rooibostee saam te stel. Terme wat die meeste voorgekom het, is gekies om in ‘n sensoriese leksikon vervat te word wat ‘n definisie en ‘n verwysingstandaard vir elke term voorstel. Die “karakteristieke” sensoriese eienskappe van goeie kwaliteit rooibostee kan soos volg gedefinieer word: ’n kombinasie van “heuning”, “houtagtige” en “fynbos-blom” geure met ‘n effense soet smaak en ‘n sagte vrankheid. Aangename “karamel” en “vrugtige-soet” geure is ook waargeneem, terwyl terme soos “groen” en “hooi” met swak kwaliteit rooibostee geassosieer is. Groot variasie in die samestelling van rooibostee is verkry deur kwantifisering van die inhoud van oplosbare vastestowwe (SS), totale polifenole (TP), tanniene, en 14 monomeriese fenoliese verbindings, asook spektrofotometriese kleurmetings. Hoë kwaliteit rooibostee is geassosieer met hoër vlakke van SS, TP, tanniene en fenoliese verbindings in vergelyking met lae kwaliteit rooibos. Korrelasies tussen laasgenoemde parameters en die sensoriese eienskappe het aangedui dat sekere nie-vlugtige verbindings, bv. fenielpirodruiwesuurglukosied, kwersetien-3-glukosied en iso-orientien, geassosieer is met die kenmerkende soet smaak van rooibos, terwyl ‘n bitter smaak geassosieer is met spesifieke flavonoïede soos luteolien, kwersetien and aspalatien. Die enigste verbinding wat betekenisvol gekorreleer het met vrankheid was rutien, maar dit is waarskynlik dat aspalatien en ander monomeriese flavonoïede ook bygedra het tot vrankheid. Die tannieninhoud het nie verband gehou met vrankheid nie, vermoedelik as gevolg van die beperkinge van die chemiese metode vir tannienbepaling. Om te bepaal of stoompasteurisasie van rooibos die sensoriese kwaliteit en chemiese samestelling van rooibostee beïnvloed, is die verskille in fenoliese samestelling en sensoriese eienskappe van die tee, berei van ongepasteuriseerde en gepasteuriseerde rooibos, ondersoek. Stoompasteurisasie het ‘n betekenisvolle verlaging teweegebring van die SS, TP en aspalatien inhoud, sowel as van die absorbansie van die tee, veral by ‘n golflengte van 450 nm. Dit het ook gelei tot ‘n statisties betekenisvolle vermindering van die intensiteit van die meeste aroma en geur eienskappe, veral die sogenaamde “groen” eienskap wat met swak kwaliteit rooibos verbind word. As gevolg van stoompasteurisasie is die opmerklike “groen” geur van sekere ongepasteuriseerde monsters herhaaldelik vervang deur ‘n “hooi” geur. Die smaakeienskappe, soet en bitter, was onveranderd, terwyl vrankheid statisties betekenisvol afgeneem het as gevolg van pasteurisasie.

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Wang, Chia-Lin. "Probiotic lactobacilli as a soy yogurt starter culture - microbiological, chemical and sensory analyses /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1422974.

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Apelman, Linnea. "Hur beskrivs sensoriska egenskaper inom deskriptiv analys? : En kvantitativ tvärsnittstudie av artiklar publicerade 1974-2019." Thesis, Umeå universitet, Institutionen för kost- och måltidsvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-179774.

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Bakgrund Deskriptiv sensorisk analys (DSA) syftar till att beskriva sensoriska egenskaper (attribut) hos livsmedelslprodukter. En bedömarpanel analyserar ett produktprov genom att identifiera, namnge och mäta intensiteten hos ett antal attribut. Syfte Syftet med undersökningen var att studera hur attribut identifieras, beskrivs och presenteras inom vetenskaplig tillämpning av DSA. Metod Sjuttiofyra artiklar, publicerade i vetenskapliga tidskrifter mellan 1974 och 2019, analyserades kvantitativt med hjälp av deskriptiv statistik. Sjutton variabler användes för datainsamling. Samband mellan variablerna analyserades med hjälp av statistiska tester. Resultat Av artiklarna var 96 % publicerade i tidskrifter utan specifik inriktning mot sensorisk analys. I två tredjedelar av artiklarna tillämpades generisk deskriptiv analys (GDA). I fler än hälften av artiklarna avvek panelen från vad som rekommenderas kring bedömarantal eller tid för träning. I snitt användes 1,4 ord för namngivning av attributen. I hälften av artiklarna definierades inte attributen. I två tredjedelar av artiklarna presenterades inte några referensprodukter för att illustrera skalstegen. I tre fjärdedelar av artiklarna presenterades attributen i metodbeskrivningen. Meddelandelen substantiv var 68,2 % och 31 % adjektiv. En måttlig negativ korrelation mellan andelen substantiv och tiden för träning av bedömarpanelen var statistiskt signifikant. Slutsats I många vetenskapliga studier utförs DSA utan att gällande rekommendationer kring bedömarpanelen följs. I artiklar publicerade i vetenskapliga tidskrifter presenteras attributen inprecist nog att ifrågasätta användbarheten hos resultaten. Att ge den kvalitativa delen av undersökningen, identifiering och namngivning av attributen, status resultat skulle kunna öka intresset för att definiera attributen och illustrera skalstegen, vilket är en förutsättning för att tolka det kvantitativa resultatet (intensitetsmätningen) på ett meningsfullt sätt.
Background Descriptive sensory analysis (DSA) aims to describe the sensory attributes of food products. A panel of assessors analyze a sample of the product to identify and name a set of attributes and estimate their intensity. Objective The aim of the study was to research how attributes are identified, described and presented in the scientific use of DSA. Method By using descriptive statistics, 74 articles published in scientific journals between 1974 and 2019 were analyzed quantitatively. Data collection was conducted using 17 variables. Correlations between variables and differences between groups were analyzed using statistical tests. Results Of the articles 96 % were published in non-sensory-specific journals. Generic descriptive analysis (GDA) was used in two thirds of the articles. In more than half of the articles the number of assessors, or the time spent on assessor training, differed from what is recommended. An avarage of 1.4 descriptive words were used to name each attribute. In half of the articles no definitions of the attributes were given. In two thirds of the articles no reference products were presented to illustrate the attributes or different points of the scale. In three quarters of the articles the attributes were presentet in the section of method description, and not the results. The avarage share of nouns was 68.2 % and 31 % adjectives. A moderate negative correlation between the share of nouns and the time spent on panel training was significant. Conclusion Sometimes DSA is used without panel recommendations being followed. There are scientific articles where the sensory attributes are presented vaguely enough to question the usability of the results. To interperet naming of the sensory attributes as a qualitative results could motivate a more defined presentation, which would benefit the quantitative result (intensity assesment) by explaining what is meassured.

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Botha, Janita J. "Sensory, chemical and consumer analysis of Brettanomyces spoilage in South African wines." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4141.

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Thesis (MSc Food Sc (Food Science))--University of Stellenbosch, 2010.
ENGLISH ABSTRACT: This study focussed on the sensory effects of the main volatile compounds produced by Brettanomyces yeast causing spoilage in wine. This research firstly aimed to determine the detection thresholds of eight Brett-related spoilage compounds in wine. The second aim was to determine the sensory effect of the four most important Brett-related compounds when present individually in wine. The third aim was to determine the sensory effects of these four compounds when present in wine in a range of combinations, and to further investigate their effect on consumer liking. Finally, this project aimed to investigate the incidence of these compounds in a small range of South African wines. The sensory detection thresholds of 4-ethylphenol, 4-ethylguaiacol, 4-ethylcatechol, 4- vinylphenol, 4-vinylguaiacol, isovaleric acid, isobutyric acid and acetic acid were determined. Apart from 4-ethylcatechol, these values generally agreed well with recent literature where values determined in wine are available. However, the discrepancies highlighted the importance of the effect of the medium (wine) when determining sensory detection thresholds. The use of the median as alternative calculation method was also investigated, and it was found that this method gives more insightful results than the standard American Society of Testing Materials (ASTM E679-04) method. Four compounds, namely 4-ethylphenol, 4-ethylguaiacol, 4-ethylcatechol and isovaleric acid were profiled individually in wine using a trained sensory panel. It was found that all four compounds caused a suppression of the natural berry-like character in the wine, which induced a sick-sweet character. 4-ethylphenol contributed Elastoplast™ and leather aromas in the wine, both of which are commonly associated with Brettanomyces taint. 4-ethylguaiacol added a medicinal aroma to the wine, and 4-ethylcatechol and isovaleric acid were responsible for savoury and pungent aromas, respectively. 4-ethylphenol, 4-ethylguaiacol, 4-ethylcatechol and isovaleric acid were also profiled in combination according to the central composite design. Several univariate and multivariate methods were applied to the dataset obtained. PARAFAC, a multiway method not widely utilized regarding sensory data, was applied to the data, the results of which were complementary to those obtained during univariate and multivariate analyses. It was found that there is a great deal of interaction between the four compounds profiled in terms of sensory effects. The most notable was the Elastoplast™ attribute, the intensity of which was affected by all four compounds. The pungent attribute was also affected by the 4-ethylphenol concentration. Consumer analysis revealed that some of the samples spiked with Brettanomyces-spoilage compounds were preferred to the unspiked (control sample). However, no further relationship could be found between consumer liking and either chemical composition or sensory profile. It is therefore speculated that consumer liking of Brettanomyces infected wine is driven by more complex sensory or socio-demographic factors. Finally, the concentration of 4-ethylphenol, 4-ethylguaiacol, 4-ethylcatechol, 4-vinylphenol, 4- vinylguaiacol, isovaleric acid, isobutyric acid and acetic acid was determined in a small set of South African wines, selected to contain a high proportion of wines spoiled by Brettanomyces. Significant correlations were found between 4-ethylphenol and 4-ethylguaiacol, as well as 4- ethylphenol and isovaleric acid. However, no correlation could be found between 4-ethylphenol and 4-ethylcatechol. It is speculated that this lack of relationship is due to the different precursor profiles present in the analysed wines. This study paved the way for future investigations on the sensory effects of Brettanomyces spoilage in Pinotage red wine.
AFRIKAANSE OPSOMMING: Hierdie studie het gefokus op die sensoriese invloed van die belangrikste vlugtige komponente wat deur die Brettanomyces gis geproduseer word en bederf veroorsaak in wyn. Eerstens is gefokus op die bepaling van die deteksiedrempelwaardes van agt Brett-verwante bederwende komponente. Die tweede doelwit was om die sensoriese invloed van vier van die mees belangrike Brett-komponente te bepaal wanneer hulle individueel in wyn voorkom. Die derde doelwit was om die sensoriese invloed van hierdie vier komponente te bepaal wanneer hulle in verskillende kombinasies in wyn voorkom, asook die effek daarvan op verbruikervoorkeur. Laastens is gepoog om die voorkoms van hierdie komponente in ‘n klein seleksie van Suid- Afrikaanse wyne te bepaal. Die sensoriese deteksiedrempelwaardes vir 4-etielfenol, 4-etielguaiacol, 4-etielcatechol, 4- vinielfenol, 4-vinielguaiacol, isovaleraatsuur, isobuteraatsuur en asynsuur is bepaal. Met die uitsondering van 4-etielcatechol het die waardes oor die algemeen goed ooreengestem met waardes wat onlangs in die wetenskaplike literatuur gepubliseer is. Die uitsonderings het egter die belangrikheid van die medium (wyn) gedurende die bepaling van sensoriese deteksiedrempelwaardes uitgelig. Die gebruik van die mediaan as ‘n alternatiewe berekeningsmetode is ook ondersoek en daar is gevind dat hierdie metode meer insiggewende resultate lewer as die standaard American Society of Testing Materials (ASTM E679-04) metode. Vier komponente naamlik 4-etielfenol, 4-etielguaiacol, 4-etielcatechol en isovaleraatsuur is individueel in wyn geprofileer met behulp van ‘n opgeleide sensoriese paneel. Daar is gevind dat al vier die komponente die natuurlike bessiekarakter in die wyn onderdruk terwyl dit aanleiding gee tot ‘n onnatuurlike soet karakter. 4-etielfenol is gekenmerk aan Elastoplast™ en leeragtige aromas in die wyn en beide van hulle word algemeen geassosieer met Brettanomyces bederf. 4-etielguaiacol het ‘n medisinale aroma tot die wyn toegevoeg en 4- etielcatechol en isovaleraatsuur het respektiewelik souterige (“savoury”) en sterk (“pungent”) aromas tot gevolg gehad. 4-etielfenol, 4-etielguaiacol, 4-etielcatechol en isovaleraatsuur is ook in verskeie kombinasies geprofileer volgens die sentrale saamgestelde ontwerp (“central composite design”). Verskeie enkelveranderlike en meerveranderlike statistiese analisemetodes is ook op die datastel uitgevoer. PARAFAC, ‘n meerrigtingsmetode wat nie normaalweg vir sensoriese analise data gebruik word nie, is ook uitgevoer op die data en die resultate was komplimentêr tot die van die enkelveranderlike en meerveranderlike analisemetodes. Daar is gevind dat, met betrekking tot sensoriese effekte, daar noemenswaardige interaksie tussen die vier komponente plaasvind. Die mees opmerklike hiervan was die Elastoplast™ aroma, waarvan die intensiteit deur al vier die ander komponente geaffekteer is. Verder is die sterk (“pungent”) aroma beïnvloed deur die 4-etielfenol konsentrasie. Verbruikersvoorkeur-analise het aangedui dat sommige van die monsters waarby Brettanomyces bederwende komponente gevoeg is, verkies word bó die kontrole-wyn. Daar kon egter geen verdere verband gevind word tussen die verbruiker se voorkeur en, nog die chemise komposisie of sensoriese profiele, van die wyn nie. Daar kan dus gespekuleer word dat verbruiker voorkeur van Brettanomyces bederfde wyn gedryf word deur meer komplekse en sosio-demografiese faktore. Laastens is die konsentrasies van 4-etielfenol, 4-etielguaiacol, 4-etielcatechol, 4-vinielfenol, 4- vinielguaiacol, isovaleraatsuur, isobuteraatsuur en asynsuur in ‘n seleksie van Suid-Afrikaanse wyne bepaal. Dié wyne is spesifiek so gekies sodat ‘n aansienlike aantal van hulle met Brettanomyces bederf was. Betekenisvolle korrelasies is gevind tussen 4-etielfenol and 4- etielguaiacol, sowel as 4-etielfenol en isovaleraatsuur. Daar is egter geen korrelasie tussen 4- etielfenol and 4-etielcatechol gevind nie. Daar word vermoed dat hierdie gebrek aan korrelasie te wyte is aan die voorloperkomponent profiele teenwoordig in die wyne. Hierdie studie het die weg gebaan vir verdere ondersoeke na die sensoriese effekte van Brettanomyces bederf in Pinotage rooi wyn.

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Swaney-Stueve, Marianne. "Descriptive analysis by children, inexperienced and experienced adults, and comparisons among the groups /." free to MU campus, to others for purchase, 2001. http://wwwlib.umi.com/cr/mo/fullcit?p3036863.

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Magnuson, Shelby M. "Descriptive analysis of pecan cultivars, a comparison of raw and roasted pecans, and how pecan flavor changes over time." Thesis, Kansas State University, 2015. http://hdl.handle.net/2097/20104.

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Master of Science
Food Science Institute - Human Nutrition
Kadri Koppel
Pecan [Carya illinoinensis(Wangenh.) K. Koch] is a native North American nut tree that has progressed into a significant agricultural crop. Flavor characteristics were evaluated for sixteen pecan cultivars: ‘Giles’, ‘Hirschi’, ‘Maramec’, ‘Oswego’, ‘Lakota’, ‘Chetopa’, ‘Colby’, ‘Witte’, ‘Dooley’, ‘Kanza’, ‘Pawnee’, ‘Stuart’, ‘Chickasaw’, ‘Peruque’, ‘Major’, and ‘Henning’ using descriptive sensory analysis. A trained panel consisting of six panelists first developed a vocabulary for the raw pecans and scored the intensities of the samples for 20 flavor attributes. Results showed that the sixteen samples differed significantly (P ≤ 0.05) on 10 of the attributes. ‘Giles’, ‘Lakota’, and ‘Pawnee’ differed from the other 13 cultivars for the majority of the attributes. The remaining thirteen cultivars showed few differences in individual attribute ratings, but did show differences when mapped using multivariate techniques indicating as many as two clusters of pecan cultivars based on flavor. The same sixteen cultivars were then roasted and evaluated using descriptive sensory analysis by the same trained panel using the same 20 flavor attributes. Three texture attributes were also evaluated. These results were compared to the results from the raw pecans. Results showed that 4 attributes differed significantly across all cultivars when raw and roasted flavor was compared. Ten of the flavor attributes had higher intensities for the roasted pecans than for the raw pecans. Most of these attributes fell within the categories of ‘nutty’ and ‘sweet’. When pecans were roasted many flavor attributes were intensified, as compared to when they were raw. How the flavor of the sixteen cultivars changed over a 12 month period was then evaluated. Raw pecans were evaluated when fresh, at 3 months, 6 months, 9 months, and 12 months by descriptive sensory analysis. A trained six member panel evaluated four flavor attributes at all five time points. Results showed that bitter had the highest intensity scores for all 16 cultivars at all 5 time points. Rancidity increased over time and sweetness decreased over time for all attributes. The results from these studies can be used as a baseline for future pecan research.

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Brown, Marissa. "Sensory characteristics and classification of commercial and experimental plain yogurts." Thesis, Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/4114.

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Liou, Bo-Kang. "Sensory analysis of low fat strawberry ice creams prepared with different flavor chemicals and fat mimetics." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/4497.

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Thesis (Ph. D.) University of Missouri-Columbia, 2006.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 3, 2007) Includes bibliographical references.

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Li, Han. "Development of a preference ranking procedure with dogs." Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/36230.

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Master of Science
Department of Human Nutrition
Kadri Koppel
Palatability of pet food is an important factor influencing food purchase decision of pet owners. In industry, single- or two-bowl methods are traditionally used to determine food acceptance or preference by pets but shortcomings exist to these methods. The first objective of this study was to propose and develop a preference ranking procedure. Preliminary testing consisted of five phases each lasting five days. Each day twelve beagles were presented 5 treats encased in identical rubber toys (“kongs”). The order of selection was considered as the ranking of preference. The five phases consisted of training, testing lab-baked treats formulations with five varieties of fats, starches and proteins, and commercial foods. The dogs generally ranked 1-2 flavors above others, indicating this procedure could be a more efficient method to determine preference since more samples can be evaluated simultaneously. The second objective was to validate this procedure by following the same process as the preliminary test. The results from phases 2 to 4 showed a similar pattern. For phase 5, various treat formulations were tested by combining the most to least preferred ingredients in each category. The results proved that the ranking of the formulations resembled the preference of the dogs for individual ingredients. Therefore, this procedure was concluded to be reliable. The third objective was to use descriptive sensory analysis to study the sensory characteristics of the treats and gain insights on the drivers of dogs’ preference. Five highly trained panelists profiled the aroma of the treats and the data was analyzed with the preference results collected from the dogs. The external preference maps showed that fish and meaty aromatics tended to be liked by the dogs and grain and musty/dusty aromatics appeared to be disliked. The last objective of this study was to further explore the applications of this procedure by studying the effect of toy/puzzle toy of the treat and ingredient dosage/ratio. With the same dogs, Styrofoam cups (puzzle toy alternative) and kongs were evaluated separately with the same treats. The results collected with Styrofoam cups were similar but less discriminating than kongs. It potentially suggested that the difficulty level of the toy can affect the significance of the dogs’ preferences. No significant preference was observed when testing the treats with different ratio of the most and the least preferred protein sources, although the human descriptive panel was able to provide different profiles for the samples. In conclusion, the preference ranking procedure is a reliable test method but more research is necessary to further explore applications.

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Ng, Sing Kwei. "Application of microwave sensors for rapid food analysis." Thesis, Manchester Metropolitan University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.479020.

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Miller, Ashley E. "Descriptive analysis of black walnut cultivars and relationship between consumer acceptance and descriptive analysis of black walnuts in a sugar cookie base." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/14638.

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Master of Science
Food Science - Human Nutrition
Delores Chambers
Researchers evaluated the flavor characteristics of seven black walnut (Juglans nigra L.) cultivars: Brown Nugget, Davidson, Emma K, Football, Sparks 127, Sparrow, and Tomboy using descriptive sensory analysis. Seven trained panelists developed a lexicon for the black walnuts and scored the intensities of the samples for 22 flavor and taste attributes. Results showed that the 7 samples differed significantly (P ≤ 0.05) on 13 of the attributes. For the majority of the attributes, only Emma K differed from the rest of the cultivars by being characterized with lower scores for black walnut ID, overall nutty, nutty-grain-like, nutty-buttery, floral/fruity, oily, and overall sweet. It also was higher in acrid, burnt, fruity-dark, musty/earthy, rancid, and bitter attributes. Researchers then incorporated the black walnut cultivars into a simple cookie recipe and evaluated the samples for differences in flavor attributes using the same trained panelists. Nine of the 25 attributes differed significantly across cultivars: black walnut ID, overall nutty, nutty-buttery, brown, toasted, acrid, rancid, overall sweet, and sweet (P ≤ 0.05). Lower mean scores in black walnut ID, overall nutty, and sweet and higher mean scores in rancid and acrid characterized the Emma K cookie. A PCA biplot revealed that cookies with Football, Sparks 127, and Sparrow walnuts related with one another and the attributes nutty-woody, leavening, and piney. A consumer acceptance test for six of the cookies (Tomboy cultivar was excluded) was also performed. There were four significant clusters of consumers that differed in their acceptance of the cookie samples. Cluster 1 preferred Football, clusters 2 and 3 each showed no overall preference, and cluster 4 preferred Emma K suggesting a set of niche consumers for black walnut cookies. Results presented in this paper can assist black walnut growers in determining which cultivars to plant and harvest. By knowing which cultivars have the most desirable flavor characteristics, growers can focus time and resources on select cultivars, therefore resulting in higher quality black walnuts as products to be sold to consumers in various formats. By consciously choosing which cultivars to harvest, black walnut growers can meet market demand and increase profit.

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Hanekom, Evette. "Chemical, sensory and consumer profiling of a selection of South African Chenin blanc wines produced from bush vines." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/71812.

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Thesis (MScFoodSc)--Stellenbosch University, 2012.
ENGLISH ABSTRACT: Twenty five commercial Chenin blanc wines produced solely from bush vine vineyards and including three vintages, three styles and five production areas, were sourced for this study. Descriptive sensory analysis (DSA) and chemical analyses including GC-FID (gas chromatography fitted with a flame ionisation detector) and FTMIR (Fourier transform mid-infrared) spectroscopy were employed to establish the sensory and chemical characteristics, whereas consumer tests were conducted to determine consumer perception and liking of bush vine Chenin blanc wines. DSA (a profiling technique) was also compared to the sorting task (a classification technique) with a description assignment to evaluate the sorting task’s ability to profile wines. According to the results of DSA, the wines separated into two groups. One group associated with sensory attributes which can be considered indicative of the Fresh and Fruity Chenin blanc style. The other group associated with sensory attributes which can be considered indicative of the Rich and Ripe style of Chenin blanc. No separation between the wooded and unwooded Rich and Ripe styles was apparent. According to the results of the chemical analyses, the wines also separated into two groups. This separation seemed to be caused by vintage and the chemical changes associated with ageing as the wines from the youngest vintage (2010) was strongly associated with high levels of esters and malic acid. The older wines were situated farthest away from these attributes indicating low concentrations. When comparing the results from the sorting task and DSA, it could be seen that similar wine style groupings formed, indicating that DSA can also be regarded as an effective tool when categorising wines. The differences in the positioning of some of the wines and attributes on the DSA multivariate plots and the sorting task plots could be attributed to the difference in panels used. The sorting task was conducted using an expert panel with persons illustrating significant technical knowledge of Chenin blanc wines. Experience, exposure and technical knowledge tend to establish a common language amongst wine experts which could have caused the expert panel to perceive some wines differently when comparing the results of the latter panel to that of the trained panel. DSA was found to remain the most effective method for establishing a comprehensive sensory profile. Consumer analyses showed that regular white wine drinkers prefer the unwooded styles (Fresh and Fruity and Rich and Ripe unwooded) of Chenin blanc more than the wooded style. It was also found that consumers with a higher level of objective wine knowledge tend to associate the terms ‘bush vine’ and ‘old bush vine’ with the Rich and Ripe style of Chenin blanc, whereas consumers with a lower level of objective wine knowledge associated ‘old bush vine’ with the Fresh and Fruity style. Since all the wines used in the consumer analysis were produced from old bush vines, it is evident that consumer education on the impact of bush vine training system and vine age on wine quality is needed. Better understanding of these principles could lead to elevated product appraisals and consumer satisfaction.
AFRIKAANSE OPSOMMING: Vyf en twintig kommersiële Chenin blanc wyne, uitsluitlik van bosstok wingerde geproduseer, is bekom vir hierdie studie. Die wyne het drie style, drie oesjare en vyf produksiestreke ingesluit. Beskrywende sensoriese analise (BSA) en chemiese analises, wat GC-FID (gas chromatografie gekoppel met vlam-ioniserende deteksie) en FTMIR (Fourier-transformering mid-infrarooi) spektroskopie insluit, is uitgevoer om onderskeidelik die sensoriese en chemiese eienskappe van die wyne te bepaal. Verbruikerstoetse is ook uitgevoer om verbruikerspersepsie en -voorkeure vir bosstok Chenin blanc wyne te bepaal. BSA (‘n profilerings tegniek) was ook vergelyk met ‘n sorterings taak (‘n klassifikasie tegniek) met ‘n beskrywings opdrag, primêr om die sorterings taak se vermoë om wyne te profileer te ondersoek. Volgens die resultate van BSA, het die wyne in twee groepe verdeel. Een groep het met die sensoriese eienskappe wat op ‘n Vars-en-Vrugtige-styl dui, geassosieër. Die ander groep het met sensoriese eienskappe geassosieër wat met die Volrond-styl verband hou. Geen verdeling tussen die gehoute en ongehoute wyne binne die Volrond-styl was sigbaar nie. Volgens die resultate van die chemiese analises, het die wyne ook in twee groepe verdeel. Die verdeling blyk asof dit veroorsaak is deur oesjaar en die chemiese veranderinge wat met wynveroudering gepaard gaan. Wyne van die jongste oesjaar (2010) het ‘n sterk verband met hoë vlakke van esters en appelsuur getoon. Die ouer wyne was verder weg van hierdie eienskappe geleë, wat op laer ester en appelsuur konsentrasies dui. Wanneer die meerveranderlike resultate van die sorterings taak (met en sonder die aanduiding van sensoriese eienskappe) en dit van BSA vergelyk word, kon soortgelyke groeperings gesien word. Dit is ‘n aanduiding dat BSA ook wyne effektief kan kategoriseer. Die verskil in posisionering van sommige wyne tussen die BSA en sorterings taak resultate, kan toegeskryf word aan die verskillende panele wat gebruik is om die tegnieke uit te voer. ‘n Deskundige paneel (wynkenners) is gebruik om die sortingstaak uit te voer. Ervaring, blootstelling en tegniese kennis is geneig om te lei tot die vestiging van ‘n gemeenskaplike taal onder wynkenners. Hierdie gemeenskaplike taal kan as rede aangevoer word vir die uiteenlopende analise van sommige wyne wanneer die resultate van die deskundige paneel met dié van die opgeleide paneel (in BSA gebruik) vergelyk word. Dit is gevind dat BSA, wanneer ‘n omvattende sensoriese profiel bepaal moet word, die mees effektiefste metode bly. Verbruikerstoetse het getoon dat gereelde witwyn-verbruikers die ongehoute Chenin blanc style (Vars-en-Vrugtig en ongehoute Volrond) bo die gehoute styl verkies. Dit is ook bepaal dat verbruikers met ‘n hoër vlak van objektiewe wynkennis neig om die terme ‘bosstok’ en ‘ou bosstok’ met die Volrond-styl van Chenin blanc te assosieer, terwyl verbruikers met ‘n laer vlak van objektiewe wynkennis die term ‘ou bosstok’ met die Vars-en-Vrugtige Chenin blanc styl assosieër. Aangesien al die wyne wat in die verbruikerstoetse ingesluit is van ou bosstok wingerde geproduseer is, is dit duidelik dat verbruikeropvoeding insake die effek van die gebruik van bosstokke en ou wingerdstokke op wynkwaliteit noodsaaklik is. ‘n Beter begrip van hierdie beginsels sal lei tot verhoogde produkwaardasie, asook ‘n toename in verbruikertevredenheid.

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Talavera, Bianchi Martin Jose. "Sensory analysis of pac choi and tomato grown under organic and conventional systems." Diss., Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1627.

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Yenket, Renoo. "Understanding methods for internal and external preference mapping and clustering in sensory analysis." Diss., Kansas State University, 2011. http://hdl.handle.net/2097/8770.

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Doctor of Philosophy
Department of Human Nutrition
Edgar Chambers IV
Preference mapping is a method that provides product development directions for developers to see a whole picture of products, liking and relevant descriptors in a target market. Many statistical methods and commercial statistical software programs offering preference mapping analyses are available to researchers. Because of numerous available options, there are two questions addressed in this research that most scientists must answer before choosing a method of analysis: 1) are the different methods providing the same interpretation, co-ordinate values and object orientation; and 2) which method and program should be used with the data provided? This research used data from paint, milk and fragrance studies, representing complexity from lesser to higher. The techniques used are principal component analysis, multidimensional preference map (MDPREF), modified preference map (PREFMAP), canonical variate analysis, generalized procrustes analysis and partial least square regression utilizing statistical software programs of SAS, Unscrambler, Senstools and XLSTAT. Moreover, the homogeneousness of consumer data were investigated through hierarchical cluster analysis (McQuitty’s similarity analysis, median, single linkage, complete linkage, average linkage, and Ward’s method), partitional algorithm (k-means method), nonparametric method versus four manual clustering groups (strict, strict-liking-only, loose, loose-liking-only segments). The manual clusters were extracted according to the most frequently rated highest for best liked and least liked products on hedonic ratings. Furthermore, impacts of plotting preference maps for individual clusters were explored with and without the use of an overall mean liking vector. Results illustrated various statistical software programs were not similar in their oriented and co-ordinate values, even when using the same preference method. Also, if data were not highly homogenous, interpretation could be different. Most computer cluster analyses did not segment consumers relevant to their preferences and did not yield as homogenous clusters as manual clustering. The interpretation of preference maps created by the highest homogeneous clusters had little improvement when applied to complicated data. Researchers should look at key findings from univariate data in descriptive sensory studies to obtain accurate interpretations and suggestions from the maps, especially for external preference mapping. When researchers make recommendations based on an external map alone for complicated data, preference maps may be overused.

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Polowsky, Patrick. "Analysis of surface crystals on soft washed rind cheeses using polarized light microscopy and their effect on the sensory perception of grittiness." ScholarWorks @ UVM, 2018. https://scholarworks.uvm.edu/graddis/864.

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With the rising popularity of artisanal cheese in the United States, the soft washed rind category has emerged as a fast-growing segment of the marketplace. There is much anecdotal evidence to suggest a common sensorial defect in soft washed rind cheese is a gritty/sandy texture attributed to crystal growth on the rind of these cheeses A preliminary study was undertaken to develop a set of criteria to visually identify crystals found on soft washed rind cheeses. Single crystal identities were presumptively determined using polarized light microscopy (PLM), and cross-checked using powder x-ray diffractometry (PXRD). Two distinct crystal groupings were determined based on these metrics. Group 1 crystals had high birefringent coloring, angle of extinction (AE) ≈ 90°, and were smaller and less circular than Group 2 crystals (P<0.05). Group 2 crystals had no birefringent coloring and AE ≈ 18°. Using established mineralogical data, Group 1 and Group 2 crystals were identified to be struvite and ikaite, respectively. These crystalline bodies are situated in an amorphous cheese matrix (i.e. smear), which create difficulties when examining via PLM and PXRD, leading to high background noise. To remedy these issues, a novel method for harvesting crystals was developed. Smear scrapings were immersed in NaOH (pH=10) to dissolve smear material, which resulted in improved PLM and PXRD performance. A subsequent observational study was conducted to understand the prevalence of surface crystals and grittiness associated with washed rind cheeses sourced from the U.S.A. and Europe. Crystal types were identified via PXRD and PLM. Crystal size and shape (circularity) metrics were determined via PLM and image analysis. A descriptive sensory panel (n=12) was used to evaluate grittiness presence and intensity. Identified crystal types included ikaite, struvite, calcite, and brushite. Mean crystal length and area ranged from ~30μm to ~1100μm, and ~500μm2 to ~200,000μm2, respectively. Sensory perception threshold for grittiness occurred at a mean crystal length of ~70μm and mean crystal area of ~2900μm2. Below these threshold levels, cheeses presented with negligible grittiness. Above these threshold levels, grittiness was highly correlated with crystal length and area (r=0.93 and 0.96, respectively; P<0.001). These results indicate surface crystals have a direct impact on the sensorial quality of soft washed rind cheeses.

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Ledeker, Christie N. "Differences in sensory characteristics among various mango cultivars in the form of fresh sliced mango, mango purée, and mango sorbet." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/12125.

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Master of Science
Food Science Institute, Human Nutrition
Delores H. Chambers
Fresh mangoes are highly perishable, and therefore, they are often processed to extend shelf-life and facilitate exportation. Studying the transformation that mango cultivars undergo throughout processing can aid in selecting appropriate varieties for products. In the 1st part of this study, the flavor and texture properties of 4 mango cultivars available in the United States (U.S.) were analyzed. Highly trained descriptive panelists in the U.S. evaluated fresh, purée, and sorbet samples prepared from each cultivar. Purées were made by pulverizing mango flesh, passing it through a china cap, and heating it to 85 °C for 15 s. For the sorbets, purées were diluted with water (1:1), sucrose was added, and the bases were frozen in a batch ice cream freezer. Much of the texture variation among cultivars was lost after fresh samples were transformed into purées, whereas much of the flavor and texture variation among cultivars was lost once fresh mangoes and mango purées were transformed into sorbets. Compared to the other cultivars, Haden and Tommy Atkins underwent greater transformations in flavor throughout sorbet preparation, and processing reduced the intensities of some unpleasant flavors in these cultivars. Tommy Atkins was the only cultivar that had flavor differences from other cultivars when it was in sorbet. Results suggest that cultivar variation is generally not detectable in mango sorbet unless the cultivar has a distinct initial flavor. In the 2nd part of this study, descriptive panelists in Thailand evaluated the flavor and texture properties of fresh samples and purées prepared from 6 cultivars grown in Thailand. Thermal processing had unique effects on the flavor of each cultivar, especially Nam Dok Mai and Chok Anun; Nam Dok Mai significantly decreased in mango identity and peach flavors after processing, whereas Chok Anun significantly increased in sweet, mango identity, and pineapple flavors. Although a slight amount of flavor variation among cultivars was lost because of thermal processing, most of the texture variation was eliminated. Because of significant changes in flavor and texture after heat treatment of mango cultivars, manufacturers should select cultivars for mango purées based on their properties after thermal processing.

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Taylor, Kaitlyn Elizabeth. "Evaluation of Flavor Variation in Swiss Cheese from Five Factories Using Selected Ion Flow Tube Mass Spectrometry (SIFT-MS), Descriptive Sensory Analysis, and Consumer Testing." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366113857.

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Liggett, Rachel Esther. "Multivariate Approaches for Relating Consumer Preference to Sensory Characteristics." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1282868174.

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Greene, Jeffrey Lynnette. "Characterization of Naturally Occurring Fruity Fermented Off-flavor in Peanuts Using Descriptive Sensory, Consumer, and Instrumental Analyses." NCSU, 2007. http://www.lib.ncsu.edu/theses/available/etd-06192007-175623/.

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Peanuts are a valuable agricultural commodity and roasted peanut flavor is the driving force for consumer purchase and consumption. The development of off-flavors is a major concern to the peanut industry and physiological differences (i.e. oil and sugar content) among the different maturity classes can influence the presence and/or absence of specific flavors. Fruity fermented (FF) is a common off-flavor found in peanuts and is developed when peanuts are cured at excessive temperatures (>35ºC). Previous literature has characterized FF off-flavor using descriptive sensory analysis; however, there is little information on FF off-flavor using consumer evaluation. The peanut plant has an indeterminate flowering pattern meaning a range of maturities are present at harvest and the immature and mature peanuts differ in roasting and flavor quality. Immature peanuts tend to have more FF off-flavor than mature peanuts which results in a FF distribution within large peanut lots. The flowering pattern and heterogeneous distribution of immature and mature seed make it challenging to obtain an accurate determination of FF off-flavor in a bulk lot. Establishing links between flavor and volatile flavor compounds can be obtained by using sensory and instrumental analyses. Currently, there is little research published on the volatile components that contribute to naturally occurring FF off-flavor. The objectives of this research were to: i) characterize consumer?s perception of FF off-flavor, ii) measure the variability and determine the FF distribution in bulk lots, iii) and identify the volatile compounds responsible for naturally occurring FF off-flavor using sensory and instrumental analyses. Descriptive sensory analysis was conducted to determine the no FF and FF samples used for the consumer study. Two-hundred and eight consumers evaluated a control (no FF off-flavor), low (1.0 FF) intensity, and a high (3.0 FF) intensity using two different scaling techniques: category and line scales. Results indicated FF off-flavor negatively impacts consumer acceptance of peanuts and the line scales were more sensitive and showed more differences among the samples compared to the category scale. The second study investigated the distribution of FF off-flavor in peanut lots and the results indicated that FF intensity varied from lot to lot and within a single bulk lot. Solvent assisted flavor evaporation (SAFE), solidphase microextraction (SPME), gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS), and model systems were conducted to identify the compounds responsible for naturally occurring FF off-flavor. Volatile analysis indicated that ethanol and the esters previously reported as causing FF off-flavor were not detected in natural FF samples by solvent extractions; however, they were present in natural and artificially created Georgia Green and Flavor Runner 458 samples by headspace extractions. These findings emphasizes that the use of laboratory created samples should not be used to identify off-flavor sources in peanuts. Additionally, the use of analytical techniques to identify FF off-flavor in bulk lots cannot be achieved using ethanol or esters as indicators.

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Salabak, Dane E. "Determination of Sensory Characteristics and Antioxidant Capacity of Pawpaw Pulp During Frozen Storage." Ohio University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1353528036.

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Andersson, Sebastian. "En undersökning av baobabfruktens teknologiska och sensoriska egenskaper vid såstillverkning." Thesis, Högskolan Kristianstad, Avdelningen för mat- och måltidsvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-21218.

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Undersökningens målsättning var att utveckla en sås baserad på torkat baobabfruktkött. Baobab är ett träd som främst växer i Afrika och både fruktköttet, kärnorna, bladen och barken kan användas som livsmedel eller örtmedicin. Frukten har ett högt näringsinnehåll av både makronutrienter och mikronutrienter. Torkat fruktkött utvunnit från baobabfrukten användes för att skapa en stabil emulsion som smaksattes för att passa som sås till en vegansk havre/algburgare. För att undersöka vilka smaksättningar som konsumenterna gillar utfördes ett gillandetest i en matbutik. Dessutom användes en semi-tränad panel för att utföra ett beskrivande test med havre/algburgare och baobabsås. Havre/algburgarens smakprofil hade utvecklats från tidigare projekt av Aventure AB. Det beskrivande testet undersökte hur baobabsåsens smak, pH-värde och viskositet påverkar havre/algburgarens smakprofil. Undersökningarna visar att konsumenterna föredrar en sås baserad på en emulsion med lägre viskositet och att de inte gillade en neutral baobabsås. Konsumentundersökningen visade även att när baobabsåsen sväljs resulterar det i en sämre munkänslan som kan bero på de olösliga partiklarna i baobabfruktköttet. De olika smaksättningarna av emulsionerna påverkade havre/algburgarens sensoriska profil olika, den sudanska smaksättningen maskerade smaken och doften av alg medan den neutrala emulsionen ökar intensiteten av brända doften och den brända smaken i havre/algburgaren.
The study will provide a sauce based on dehydrated baobabpulp. Baobab is a tree mostly grown in Africa of which the pulp, kernels, leaves and bark can be used for food applications or as herbal medication. The fruit has a high nutritional value of both macronutrients and micronutrients. During the study, dried pulp extracted from the baobab fruit was used as an emulsifier and flavoring of a sauce adapted for a vegan oats/kelpburger. In order to investigate which flavor the consumers prefer and to determine the taste of the end product, an acceptance test is carried out in a grocery store. A semi-trained panel was used to perform a descriptive test with oats/kelpburger and baobab emulsion. The sensory profile of the oat/kelpburger were developed from a previous project av Aventure AB. The descriptive test examined how the baobabsauce taste, pH and viscosity of affect the sensory profile of oats/kelpburger. The studies show that consumers prefer a sauce based on an emulsion with a lower viscosity and do not like a neutral baobabsauce. Upon swallowing, the level of liking of texture decreases and this may be due to insoluble particles in the baobabpulp. The different flavorings of the emulsions affected the oat/kelpburger's sensory profile differently, the Sudanese emulsion masked the taste and aroma of kelp while the neutral emulsion increased the intensity of the burnt taste and aroma of the oat/kelpburger.

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Heenan, Samuel Peter, and n/a. "Sensory and instrumental characterisation of consumers perceptions of fresh baked flavour to provide direction for new product development." University of Otago. Department of Food Science, 2009. http://adt.otago.ac.nz./public/adt-NZDU20090805.144153.

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Freshness is a holistic attribute of a food product, with a meaning that most often includes how recently produced or harvested a food currently is and to what extent it has been preserved. Without knowledge of production date, consumers will judge perceived freshness by the sensory properties of foods. However, these properties are not easily identified and described, as they vary considerably between different product types. The objective of this thesis, was to determine the sensory properties that consumers most associate with baked product freshness, and to determine the volatile composition responsible for "fresh-baked" flavour. In addition, relationships were determined and modelled between volatile composition, sensory properties and perceived freshness, in order to predict perceived freshness without the need for further consumer testing. Two consumer studies were carried, where perceived freshness of 10 breads, 5 cakes and 5 biscuits was measured based on appearance, flavour and texture, and by product odour only. Individual differences in perceived freshness were represented on two-dimensional Freshness Maps generated using Principal Component Analysis (PCA). Consumers used similar terms to describe product freshness, but different terms were associated with specific product types. An understanding of the sensory characteristics associated with perceived freshness was determined by examining relationships between perceived freshness and descriptive analysis (DA). Sensory characteristics perceived to convey freshness in one product type did not necessarily convey freshness in another. Further relationships between perceived freshness and sensory characteristics were determined for 20 bread types. Descriptive analysis was carried out with all breads, whereas perceived freshness was measured for 10 of these. Three consumer clusters were identified that were homogenous in their freshness perceptions, indicating that perceived bread freshness varied among consumers. Perceived freshness of breads not evaluated by consumers, but assessed by descriptive sensory analysis, were predicted for each consumer cluster using Partial Least Squares Regression (PLSR). Most fresh breads were described as having "porous" appearance, "floury", "toasted" and "malty" odour, "sweet", "buttery", and "oily" flavour, and "sweet" aftertaste. Least fresh breads were described as "musty" odour, "sour" flavour and "sour" aftertaste. In addition, Proton Transfer Reaction Mass Spectrometry (PTR-MS) measured the volatile composition of all 20 bread types. Thirty-three mass ions significantly discriminated between bread types. Relationships were determined between odour and flavour sensory attributes, and mass spectral data using 15 of the 20 breads. PLSR models predicted the sensory properties and perceived freshness of all breads including five types not included in the construction of models. Bread perceived to be most fresh shared a similar combination of positively correlated mass ions, m/z 87, 97 and 117, also represented by "dairy" odour and "buttery" flavour, whilst the masses m/z 63, 69 and 91 were negatively associated with bread freshness, represented by the sensory attributes "grain", and "musty" odour, and "sour" flavour. The influence of sweetener, fat type and time from baking on perceived freshness was determined for cakes. Four sweeteners (sucrose, glucose, xylitol, isomaltose), three fat types (butter, margarine, shortening) and two times from baking (days zero and 15) were investigated. Descriptive analysis was carried out using a trained panel, and volatile composition of measured using PTR-MS. Twelve cake samples with the largest sensory variation were further selected for consumer testing for perceived freshness. Results demonstrated that sweetener type, fat type, time from baking and their interaction significantly influenced the sensory properties, volatile composition, and perceived freshness of cakes. There was no evidence of perceived freshness segmentation among consumers. Perceived freshness of the twelve cakes not evaluated by consumers was predicted using sensory properties, volatile composition, and their combination. The freshest cakes were evaluated on the day of baking, and contained a combination of margarine and sucrose, and butter and sucrose. The least fresh cakes were evaluated after 15 days of storage and contained a combination of shortening and isomaltose, and butter and isomaltose. The most fresh samples were positively correlated with mass ions m/z 124, 74, 97 and 93, and sensory characteristics of "buttery" odour, and "buttery", "eggy" flavour. The least fresh samples were negatively correlated with mass ions m/z 110 and 95, and sensory characteristics of "rancid", "dusty" and "fatty" odour. Best predictions were obtained for cakes evaluated on day zero that contained a combination of shortening and sucrose. This research established an objective knowledge of consumers' perceived freshness of baked product types in terms of sensory properties and volatile composition. This approach enabled the understanding of ingredients and time from baking influences, as well their interaction on baked product freshness. The predictive models developed that examined relationships between PTR-MS spectra, sensory characteristics and consumer perceived freshness can be applied to predict freshness of baked products not assessed by consumers.

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Whetstone, Sara. "Impact of seasonings on sensory attributes of beef across three cuts of steak and two USDA grades." Thesis, Kansas State University, 2012. http://hdl.handle.net/2097/13523.

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Master of Science
Department of Human Nutrition
Koushik Adhikari
Three cuts of steak (strip, chuck-eye and top blade) of two United States Department of Agriculture grades (choice and select) underwent seasoning and tenderization treatments to study whether flavor and texture quality could be enhanced within cut and grade of steak. Treatments included: 1) seasoning alone, 2) a combination of seasoning + bromelain (enzymatic tenderizer), or 3) control (no seasoning and/or bromelain). The seasoning included: kosher salt, black pepper, onion powder, garlic powder, cumin, and ground oregano. All of the steaks were cooked to an internal temperature of 71° C (medium doneness). Six trained descriptive panelists evaluated the samples. The results of this study indicate that it may be possible to improve eating quality of choice and select chuck-eye and choice top blade to be more similar to strip steaks of the same USDA grade. Both treatments increased flavor and texture attributes in these samples that have been shown to have an impact on liking scores. Choice chuck-eye samples had decreased bloody/serumy and metallic scores and increased umami and initial flavor impact with both treatments. Both treatments increased brown/roasted flavor in select chuck-eyes. Tenderness, fat-like and umami were increased with the seasoning + bromelain treatment in select chuck-eyes. Choice top blade steaks with seasoning alone had increased umami flavor. Both treatments impacted attributes (fat-like, umami and sour) of the select strip steak that differed from choice strip steaks. The next step to this research is to investigate whether consumer liking scores are consistent with conclusions made from descriptive analysis results. Overall, these treatments could be a valuable tool for beef retailers.

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Chanadang, Sirichat. "Sensory evaluation and consumer acceptability of novel fortified blended foods." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35459.

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Doctor of Philosophy
Food, Nutrition, Dietetics and Health
Edgar Chambers IV
Fortified blended foods (FBFs), which are the mixture of cereals and legumes fortified with micronutrients, have been widely used as supplementary foods for vulnerable populations such as infants and young children in developing countries around the world. The evaluation of current FBFs showed limited evidence on their effectiveness in treating childhood malnutrition, resulting the several recommendations on processing and formulation changes to improve their quality and ability to meet nutritional needs. Sensory properties are one of the important determinants for the success of the new FBFs. Therefore, sensory testing was conducted to determine the potential of novel FBFs to be used as supplementary food compared with FBF currently used in food aid programs. Descriptive sensory analysis was performed on novel FBFs along with the traditional FBF (Corn soy blend plus; CSB+) to determine sensory characteristics of each FBF. Results showed that novel FBFs had more pronounced toasted characteristics and higher sweetness than CSB+, due to the higher temperature during extrusion process and the addition of sugar in the novel formulation. In addition, novel FBFs that had higher amount of legumes (e.g. soybean, cowpea) in their formulations, especially for all sorghum cowpea blends, showed higher intensity in beany characteristics. Sensory shelf-life testing showed that novel FBFs could have shelf lives at least 2 years with no detection of off-note characteristics and these was comparable to the shelf life of the current FBF (CSB+). Sensory testing was also performed with target populations: children who eat the food and care givers who prepare it, during a 20-week field trial to determine the acceptability and preference of novel FBFs and current FBF. Results showed that all novel FBFs were highly preferred or accepted by children, even though, some of them might need longer time and more exposures to allow children to have more experience and be familiar with the food before being satisfied or preferred that food. In contrary, CSB+ that had bland flavor tended not to be well accepted and highly preferred by children compared to novel FBFs. Moreover, giving children more opportunities to consumed food prepared from CSB+ did not help to improve its acceptability or preference. Data from household visits and interview sessions showed that porridges prepared from novel FBFs required less cooking time than CSB+ and no additional ingredients needed to be added compared to CSB+ where sugar and milk were common additions. Finding from this research indicated that novel FBFs have high potential to be used successfully as supplementary food with comparable shelf life, and higher acceptability and preference to FBF currently used in food aid programs. In addition, the simple cooking of novel FBFs make them valuable to caregivers who have limited time and access to energy sources and nutrient-rich ingredients.

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Hannum, Mackenzie Elizabeth. "Developing a valid and reliable measure of engagement in consumer and sensory evaluations as a way to improve data quality." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1586518254719161.

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Syarifuddin, Adiansyah. "Multi sensory integration as a strategy to compensate for sodium and fat reduction in food." Thesis, Dijon, 2015. http://www.theses.fr/2015DIJOS088.

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Au cours des dernières années, les autorités sanitaires ont recommandé une réduction de la teneur en sel et en gras dans la consommation alimentaire quotidienne. Cependant, les aliments à teneur réduite en sel et en gras sont souvent peu appréciés par les consommateurs, ce qui a amené au développement des recherches sur les stratégies possibles pour maintenir l’acceptabilité des aliments tout en réduisant les teneurs en ces ingrédients. Dans cette thèse, l’intégration multi-sensorielle et les cinétiques de libération du sel et des arômes mesurées in vitro ont été étudiés pour évaluer leur potentialité à compenser une réduction en sel et matière grasse d’un fromage modèle de composition variable et d’un fromage réel (type trappiste).Dans une première étape, une approche sensorielle a permis d’étudier les interactions multi-sensorielles arômes-saveurs-texture pour les formages modèles et réels. La structure et la perception sensorielle de vingt-quatre modèles fromagers variant en composition (2 niveaux de gras, 2 de sel, 2 de pH à l’emprésurage) et aromatisés avec un arôme de sardine (associé au sel), d'un arôme de beurre (associé au gras) ou non aromatisés (témoin) ont été caractérisés par des mesures rhéologiques (compression uniaxiale) et des mesures sensorielles (profil descriptif). Les résultats ont montré une influence de la composition sur la structure et la texture perçue des produits. Par ailleurs, l’arôme sardine a conduit à une perception plus salé ; l’arôme de beurre a permis de renforcer la perception du caractère gras. Toutefois cette influence des arômes sur les autres dimensions sensorielles est fonction de la texture des produits donc de leur composition et de leur structure. Ces résultats ont été étendus à des fromages réels avec toutefois des spécificités. Si l’arôme sardine renforce la perception du sel, seul l’arôme de beurre associé à l’arôme de sardine permet de renforcer le caractère gras.Dans une deuxième étape, une approche physico-chimique a été développée pour explorer les cinétiques de libération des stimuli odorants et sapides dans des conditions simulant la mastication in vitro à l’aide d’un simulateur de mastication. L’objectif était d’utiliser les données ainsi obtenues pour expliquer l’influence de la structure des produits et de leur déstructuration lors de la mastication sur les effets sensoriels observés dans la première étape. Les modèles fromagers et les fromages réels ont été ainsi étudiés. La libération des composés volatils a été évaluée en connectant le simulateur de mastication à un spectromètre de masse à pression atmosphérique (PTR-MS) ; la libération du sodium a été suivie grâce à une sonde de conductivité. Les résultats ont montré une influence des trois paramètres de composition (teneur en matière grasse, en sel et pH à l’emprésurage) sur les cinétiques de la libération des arômes. Cette variation dépend néanmoins de la nature de l’arôme suivi ; les arômes plus hydrophobes étant moins sensibles aux variations de la teneur en matière grasse et plus sensibles aux variations de pH et donc à la structure du produit. La cinétique de libération du sel lors de la mastication in vitro est aussi largement influencée par la composition et la structure des produits. Outre la teneur en sel qui conditionne les quantités libérées, la teneur en matière grasse et le pH à l’emprésurage module la cinétique de libération du sel. Au final, ces travaux montrent une importante contribution de la cinétique de libération et donc probablement de la temporalité des sensations dans perception globale du sel et de la matière grasse lors de la consommation d’un aliment complexe
In recent years, health authorities worldwide advise for a reduction of salt and fat in daily food consumption. However, foods with reduced salt and fat content are often not appreciated by consumers, Therefore, the formulation of low-salt-fat foods that maintain acceptability is a major concern in food research. In this thesis, the multi-sensory integration and release kinetics of flavor compounds were explored as strategies to compensate for salt and fat reduction in cheese products (model cheeses and real cheeses). The objective was to better understand the mechanisms leading to aroma and salt release during mastication and to evaluate how the matrix composition and structure influence salt and aroma release profile.Multisensory integration approach to compensate for salt and fat reduction was studied in a first step. The structure and sensory perception of 24 cheese models varying in composition (2 levels of fat, 2 salt, 2 pH at renneting) and flavored with either a sardine aroma (associated to salt), a butter aroma (associated to fat) or not flavoured (control) were characterised by rheological measurements (uniaxial compression) and sensory evaluation (descriptive analysis). The results demonstrated an influence of the composition on the products structure and perceived texture. Furthermore, a significant saltiness enhancement was induced by sardine aroma while significant fat perception enhancement was induced by butter aroma. However, this influence of the aroma on other sensory dimensions depends on the texture of the products thus on their composition and structure. These results have been extended to real cheeses but with specificities. If the sardine flavor enhanced the perception of salt, only butter-sardine-flavor enhanced the perception of fat.In a second step, a physico-chemical approach was developed to explore the release kinetic of flavor compounds during in vitro breakdown using a chewing simulator. The aim was to use these data to explain the influence of the structure of model cheeses and real cheeses and their breakdown during chewing on sensory effects observed in the first step. Volatile compounds release was monitored by connecting the chewing simulator to a proton transfer reaction-mass spectrometry (PTR-MS), while salt release was monitored using a conductivity probe. Results showed that product composition and structure (fat, salt and pH at renneting) influenced aroma release, which however depends on the nature of the aroma: the more hydrophobic compounds are less sensitive to variations in fat content and more sensitive to variations in pH and therefore to the products structure. The salt release kinetic during in vitro chewing was also influenced by the composition and structure of the products. Indeed, beyond salt content which determined the amount of salt released, fat content and the pH at renneting modulated the release kinetic. In conclusion, this work showed a significant impact of the flavor compounds release kinetic and probably of temporality of sensations on the overall perception of salt and fat when consuming a complex food

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Maughan, Curtis A. "Development of a Beef Flavor Lexicon and Its Application to Compare Flavor Profiles and Consumer Acceptance of Grain- and Pasture-Finished Cattle." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/915.

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Flavor lexicons are used in sensory evaluation to determine the flavor profile of a food product. The objective of this study was to develop a flavor lexicon for cooked beef, which can then be used in various projects relating to beef quality such as studies investigating animal diet, marinating, ageing, or other enhancements. A descriptive panel of 10 people was used to develop a flavor lexicon of 18 attributes, including astringent, barny, bloody, brothy, browned, gamey, grassy, juicy, fatty, livery, metallic, oxidized, roast beef, and the five basic tastes (bitter, salty, sour, sweet, and umami). In contrast to other studies on beef, this lexicon was developed to include both positive and negative attributes. The lexicon was able to show that rib eye steaks from the Longissimus dorsi muscle in grass-fed animals were significantly (p<0.05) higher in barny, bitter, gamey, and grassy flavors, and lower in juicy and umami flavors. The steaks were also rated by consumers, who showed a preference for grain-fed beef over grass-fed beef. The ratings of the descriptive panel were related to the consumer panel scores to equate the lexicon terms with a positive or negative consumer degree of liking score. Those terms that were considered positive in this study due to their positive correlation with consumer liking include brothy, umami, roast beef, juicy, browned, fatty, and salty. The terms that were inversely associated with consumer liking were barny, bitter, gamey and grassy, among others. A separate descriptive panel was conducted on the Spinalis dorsi (or “cap” muscle) of the rib eye steak, with similar results. Additionally, descriptive and consumer evaluations found no difference between two types of grass diets, namely alfalfa and sainfoin. Different mixtures of beef and chicken were also evaluated to determine flavor differences between the two meats. Chicken was found to be more closely correlated to brothy, juicy, sweet, and umami, among others, while beef was found to be more closely correlated to terms such as gamey, bloody, oxidized, metallic, roast beef, and astringent. Throughout these tests, the newly developed lexicon was shown to be an effective tool for profiling fresh meat samples.

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Marques, Carla Sofia Santos. "Determinação da vida útil de pastéis sortidos." Master's thesis, ISA/UTL, 2011. http://hdl.handle.net/10400.5/4026.

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Mestrado em Engenharia Alimentar - Instituto Superior de Agronomia
This work was carried out for a benchmark company in the food retail sector and aimed to study the shelf-life of four types of assorted pastries: Bolo de arroz, Mil folhas, Palmier recheado and Jesuíta. The cakes were stored after thawing at a temperature of 20 ºC and humidity of 80% up to four days. After these periods the cakes were subjected to microbiological, physicalchemical and sensorial analysis. The values obtained were compared with the INSA (Instituto Nacional de Saúde Dr. Ricardo Jorge) microbiological values guide for assessing the microbiological quality of ready to eat food prepared in catering establishments. The Mil folhas and the Palmier recheado presented no satisfactory values ( 104 CFU of microorganisms at 30 ºC/g) for the microbiological parameters, so they were not analyzed at the sensorial level. Only the Bolo de arroz and the Jesuíta had microbiological quality that allowed the realization of these tests. From the statistical analysis performed on the answers given by the list of tasters, it was concluded that, after thawing the cakes, the zero-day´s samples and the 24 h samples were sensorially similar with p0.05, while the cakes with more time after thawing showed significant differences. The results obtained in the present work allow to conclude that, in order not to lose quality and consumer acceptability, consumption of the Bolo de arroz and Jesuíta analysed here, should be made no later than 24 hours after its thawing.

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Bastian, Mauresa. "Effects of Panelist Participation Frequency and Questionnaire Design on Overall Acceptance Scoring for Food Sensory Evaluation in Consumer Central Location Tests." BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/4446.

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Two studies were conducted to determine the effect of panelist participation frequency and specific aspects of questionnaire design on overall acceptance scoring in consumer central location tests. Regarding participation frequency, research subjects who participate frequently in some survey types are known to provide responses that differ from subjects who participate less frequently, known as panel conditioning. With respect to questionnaire design, overall acceptance (OA) question placement and usage of pre-evaluation instructions (PEI) in questionnaires for food sensory analysis may bias consumers' scores via carry-over effects. To investigate these concerns, data from consumer sensory panels previously conducted at a central location, spanning 11 years and covering a broad range of food product categories, was extracted, compiled, and analyzed. For the first study, data was analyzed to determine evidence of panel conditioning by measuring the effect of participation frequency on mean consumer OA scoring among frequent, moderate, and infrequent participants. Practical significance and occurrence of panel conditioning, defined as mean scoring differences of ≥ 0.50 on a discrete 9-point scale hedonic point, were examined. Results indicate that for overall acceptance, in general, mean scoring differences were not practically significant and did not signify occurrence of panel conditioning. For the second study, OA question placement was studied with categories designated as first (the first evaluation question following demographic questions), after non-gustation questions (immediately following questions that do not require panelists to taste the product), and later (following all other hedonic and just-about-right questions, but occasionally before ranking, open-ended comments, and/or intent to purchase questions). Additionally, each panel was categorized as having or not having PEI in the questionnaire; PEI are instructions that appear immediately before the first evaluation question and show panelists all attributes they will evaluate prior to receiving test samples. Post-panel surveys were administered regarding the self-reported effect of PEI on panelists' evaluation experience. OA scores were analyzed and compared (1) between OA question placement categories and (2) between panels with and without PEI. For most product categories, OA scores tended to be lower when asked later in the questionnaire, suggesting evidence of a carry-over effect. Usage of PEI increased OA scores by 0.10 of a 9-point hedonic scale point, which is not practically significant. Post-panel survey data showed that presence of PEI typically improved the panelists' experience. Using PEI does not appear to introduce a meaningful carry-over effect.

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Jonsäll, Anette. "Sensory quality of pork : Influences of rearing system, feed, genotype, and sex." Doctoral thesis, Uppsala University, Department of Domestic Sciences, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-517.

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Hampshire crosses of different genotype and sex were used to investigate the effects of rearing system, feed and handling on sensory quality, consumer preference and cooking loss. A selected and trained panel carried out descriptive tests. Two preference tests were carrieout by, in each case, 200 consumers.

The genotype had a major effect on sensory quality in all four studies irrespective of rearing system, feed and sex. In three of the four studies pork from RN¯ carriers scored higher for juicines, tenderness, acidulous taste and meat taste intensity.

Sex showed contradictory effects on sensory quality, while rearing system and feed had minor effects on sensory properties of pork.

Hams (M. biceps femoris) from pigs reared outdoors scored lower for juiciness and acidulous taste than hams from pigs reared indoors. Loins from pigs organically reared (KRAV) scored lower for juiciness and higher for crumbliness than ones from pigs conventionallreared.

Loins (M. longissimus dorsi) aged four days from conventionally fed pigs were juicier than ones from silage-fed pigs. When loins were aged eight days there was no difference in juicines while acidulous taste became weaker and tenderness and meat taste intensity increased.

In the case of loins stored frozen one year, those from silage-fed pigs scored higher for acidulous taste and off-flavour than those from conventionally fed pigs.

Cooking, thawing and total loss data showed minor and contradictory differences between genotypes, sexes, rearing systems and feeding regimes.

Organically and conventionally produced loins were equally liked and loins from RN¯ carrier pigs were preferred to loins from non-carriers.

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Florea, Anca Stefana. "Electrochemical affinity sensors for biomedical, food and environmental applications." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10126/document.

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Les capteurs électrochimiques sont des outils pour la détection fiable, peu coûteux, avec une haute sensibilité et sélectivité, pour la détermination des composés biologiques et chimiques dans les domaines du diagnostic clinique, l'environnement et l'industrie alimentaire. Particulièrement, les Immunocapteurs, alliant une très grande spécificité. Également des nouveaux techniques produisent des résultats similaires, par exemple, les capteurs basés sur la technique des Polymères à empreinte moléculaire, la quelle produise des récepteurs artificiels. La technique devient très important dans les sciences bioanalytiques parce qu'il porte des avantages inhérents sur les récepteurs naturels: une grande stabilité dans des diffèrent environnement et conditions, également comptent avec une grande flexibilité dans la conception, une large gamme de molécules peuvent être utilisées. L'objectif du travail présenté ici est de développer des capteurs électrochimiques avec une très grande affinité et spécificité pour une analyte. Les quelles comprennent des applications très divers comme dans la protection de l'environnement, la sécurité alimentaire et le domaine biomédical. La première partie de la thèse présent l'état actuel de la conception et techniques de fabrication des biocapteurs. Ensuite, les aspects généraux des immuno capteurs électrochimiques et capteurs base sur des aptamères sont présentés ici, ainsi que plusieurs exemples rapportés dans la littérature pour la détection de marqueurs biologiques du cancer. Les avantages de l'intégration nanomatériaux dans les dispositifs de détection sont présentés. Ensuite, plusieurs aspects sur la technique des Polymères à empreinte moléculaire sont introduits. La partie personnelle de contribution est structuré en trois chapitres: en premier temps la méthodologie et les résultats obtenus pour le développement de deux essais biologiques pour la détection du marqueur tumoral Mucinl. Le premier chapitre est dédié sur un capteur à base de billes magnétiques, dans le deuxième chapitre une capteur aptamère base sur des nanoparticules d'or sans aucun marquage et finalement un capteur basée sur la technique des Polymères à empreinte moléculaire, cette protocole a été appliqué pour la détection d'explosifs, des médicaments, des hormones et les pesticides
Electrochemical sensors provide reliable and inexpensive tools for the determination of biological and chemical compounds with high sensitivity and selectivity, in the fields of clinical diagnosis, environment protection and food industry. Immunosensors hold particular promise, combining the high specificity of immuno- reactions with the sensitivity of electrochemical methods. Artificial receptors based on molecularly imprinted technique attracted considerable attention in bioanalytical sciences due to inherent advantages over natural receptors, such as high stability in harsh conditions and freedom of molecular design towards a wide range of molecules. The aim of the thesis presented here was to develop electrochemical affinity sensors based on various recognition receptors for environment monitoring, food safety and biomedical field. The first part of the thesis reviews the current state of knowledge in these fields. General aspects of electrochemical immuno- and apta-sensors are presented herein, together with several examples reported in the literature for the detection of cancer biomarkers. The advantages of integrating nanomaterials in sensing devices are then presented. At last, several aspects of the molecularly imprinted polymers are introduced. The personal contribution part is structured in three chapters, that include the methodology and results obtained for the development of biosensors for the detection of Mucinl tumor marker, the first chapter being focused on bioassays based on magnetic beads and second chapter on a label-free aptasensor based on gold nanoparticles, and finally, a third chapter dedicated to the molecularly imprinted-based sensors for the detection of explosives, drugs, hormones and pesticides

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Doan, Alisa Rebekah. "Determining a sensory model for predicting successful and unsuccessful products: a case study of flavors for a snack category." Diss., Kansas State University, 2010. http://hdl.handle.net/2097/4329.

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Doctor of Philosophy
Department of Human Nutrition
Edgar Chambers IV
Companies introduce new products with the goal of achieving success. However, many products fail. The overall objective of this research was to design processes for determining sensory and market characteristics of food products that could predict success. The first sub-objective was to determine if success could be predicted using information known before launch. The second sub-objective was to describe a process for determining specific sensory characteristics that promote success. Most methods chosen for this research are commonly used. However, previous research has identified a relationship between consumers liking and salivation, without defining a method. Thus, three salivation methods were selected for initial testing: spit, cotton rolls and sensory scale. These were tested on foods with different textures. Although all methods gave similar results, the spit method was chosen for further testing of flavor differences. Differences in salivation measurements were found for snacks where flavors were different but texture was unchanged. Next, flavored snack products from 15 countries were selected that were successful or had failed. Questionnaires were completed for each product and included questions related to authenticity, familiarity, current trends, packaging and marketplace issues such as product competition and pricing, all of which would be known before launch. A discriminant function was developed that correctly identified 75.8% of the successful flavored snack products as successful and 66.7% of the unsuccessful products as unsuccessful. Stepwise comparisons were used to determine that four variables are necessary to correctly categorize these products. The products then were clustered into three groups to select 34 products from 11 countries for further sensory testing. Information from extensive sensory descriptive methods were evaluated individually and in various combinations through stepwise regression and discriminant analysis. The final sensory model correctly predicted all successful and unsuccessful products, had an R-square of 0.84 and included nine regression factors: seven flavor attributes and two flavor attribute ratios. Many of the attributes were base flavor notes necessary for this flavored snack category. A process for selecting key attributes for success was described. For this snack category, creating products with flavors that interact well with base flavor notes can lead to a successful product.

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Padmanabhan, Natarajan. "A novel mechanism for delivering nutrition: sorghum based fortified blended foods using extrusion." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/16302.

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Master of Science
Department of Grain Science and Industry
Sajid Alavi
The objective of the study was to investigate extrusion as an alternative processing method and grain sorghum as a viable substitute for corn in fortified blended foods (FBFs) used in nutrition and food assistance programs around the world. In the first part of this study, sorghum-soy blend (SSB), corn-soy blend (CSB) and whole corn-soy blend (WCSB) were developed using extrusion and compared with traditional CSB13 for physico-chemical and sensory properties. After milling of extrudates, average particle size (PS) ranged between 341-447 microns, with 78-85% below 600 microns. In general, Bostwick flow rates (VB=12-23 cm/min) of rehydrated blends (11.75% solids) were within standard specifications but higher than CSB13. Descriptive sensory analysis indicated that the sorghum-based rehydrated blends were significantly less lumpy and had a more uniform texture as compared to corn-based blends and CSB13. In the second part, the impact of decortication level and process conditions was investigated with respect to sorghum-based extruded blends. Degree of gelatinization of the whole sorghum-soy blend (WSSB) and decorticated sorghum-soy blend (DSSB) extrudates ranged from 93-97%. Expansion ratio (ER=3.6-6.1) was correlated with specific mechanical energy input (SME=145-415 kJ/kg; r=0.99) and average particle size after milling (PS=336-474 microns; r= -0.75). Rehydrated blends at 20% solids concentration provided recommended energy density (0.8 kcal/g) for FBFs. Bostwick flow rates had high correlation (r = -0.91) with pasting data (final viscosity) obtained using rapid visco analyzer (RVA). Addition of oil (5.5%) prior to extrusion was also studied, and resulted in process instabilities and also lower shelf-life as determined via descriptive sensory analysis (rancid and painty attributes) and gas chromatography-mass spectroscopy (hexanal, heptenal and octanal concentrations). In conclusion, extruded sorghum-soy blends met standard specifications for energy density and consistency (Bostwick flow rate), and were superior in some aspects as compared to extruded corn-soy blends and traditional corn-soy blends (CSB13). Relationships between extrusion mechanical energy input, expansion, particle size after milling and consistency of rehydrated blends were established. Consistency of the rehydrated blends is an extremely important criterion as it affects the ease of ingestion by target consumers (children below 5 years, in this case).

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Hooge, Susan E. "Impact of potassium chloride on saltiness, bitterness, and other sensory characteristics in model soup systems." Thesis, Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/691.

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RISCAZZI, PAOLA. "Nutritional, environmental optimization and sustainability communication of food productions." Doctoral thesis, Università Cattolica del Sacro Cuore, 2013. http://hdl.handle.net/10280/1742.

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La presente tesi inizia con un’analisi dell’aspetto nutrizionale degli alimenti. In particolare, è stato discusso il concetto di dieta equilibrata, con riferimento ai principi della “dieta mediterranea”. Proprio da questo modello alimentare trae ispirazione la “ottimazione”, una tecnica sviluppata e utilizzata per programmare pasti conformi a specifici standard nutrizionali (15/30/55 tra proteine, lipidi e carboidrati sull’apporto energetico totale, proporzioni tipicamente mediterranee). Tali preparazioni alimentari sono state testate anche attraverso metodi di analisi sensoriale. Il passaggio successivo è stato l’estensione del concetto di “ottimizzazione nutrizionale” a quello di “ottimizzazione ambientale”, dovuto all’ipotizzato minor impatto ambientale della dieta mediterranea. Il LCA (Life Cycle Assessment) è la tecnica che è stata utilizzata per valutare l’impatto ambientale di alcuni prodotti alimentari, quali verdure surgelate, un salume e un formaggio. Un ulteriore passaggio è stata la creazione di uno strumento di comunicazione, una nuova etichetta ambientale, realizzata per essere utilizzata dalle aziende per comunicare le loro performance ambientali e quindi il loro impegno al miglioramento continuo, e dai consumatori per ottenere maggiori informazioni sull’impatto ambientale dei prodotti acquistati quotidianamente, al fine di accrescere il proprio senso critico ed effettuare acquisti consapevoli.
The thesis begins with an analysis of the nutritional aspects of foods. In particular, the concept of balanced diet has been discussed, by referring to the principles of "mediterranean diet". Just from this food model, the “optimation” draws inspiration, a technique developed and used to plan meals consistent with specific nutritional standards (15/30/55 between protein, fat and carbohydrate on the total energy intake, typically Mediterranean). These food preparations have been tested through sensory analysis methods. The next step is the extension of "nutritional optimization" concept to the "environmental optimization” one, owing to the presumed lower environmental impact of the Mediterranean diet. LCA (Life Cycle Assessment) is the technique used to assess the environmental impact of various food products, such as frozen vegetables, cured meats, dairy products. A further step is the creation of a communication tool, a new environmental label, designed to be used by companies to communicate their environmental performance and therefore their commitment to continuous improvement, and by consumers to obtain more information on the environmental impact of the foods daily consumed, in order to increase their critical sense and make purchases in a conscious way.

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Obrdlíková, Blanka. "Stanovení vybraných vonných látek v potravinách a kosmetických výrobcích." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2014. http://www.nusl.cz/ntk/nusl-217093.

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This diploma thesis is focused on the problematic of assessment of allergenic aroma compounds in various matrices. In the frame of European legislation 26 of potentially allergenic compounds are stated, whose content in cosmetic products is limited. In the case of foods there is not such restriction so far. In the experimental part, the allergenic aroma compounds in chosen samples of cosmetic and food samples were identified and quantified using Solid phase microextraction in conjunction with gas chromatography. Sensory evaluation of aroma or taste is also included.

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Jolley, Bianca. "Development of quality control tools and a taste prediction model for rooibos." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/95991.

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Thesis (MScFoodSc)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: In this study quality control tools were developed for the rooibos industry, primarily to determine the quality of rooibos infusions. A considerable variation between samples of the same quality grade has been noted. As there are no guidelines or procedures in place to help minimise this inconsistency it was important to develop quality control tools, which could confront this problem. Both the sensory characteristics and phenolic composition of rooibos infusions were analysed in order to create and validate these quality control tools. Descriptive sensory analysis was used for the development of a targeted sensory wheel and sensory lexicon, to be used as quality control tools by the rooibos industry, and to validate the major rooibos sensory profiles. In order to ensure all possible variation was taken into account, 230 fermented rooibos samples were sourced from the Northern Cape and Western Cape areas within South Africa over a 3-year period (2011-2013). The aroma, flavour, taste and mouthfeel attributes found to associate with rooibos sensory quality were validated and assembled into a rooibos sensory wheel, which included the average intensity, as well as the percentage occurrence of each attribute. Two major characteristic sensory profiles prevalent within rooibos, namely the primary and secondary profiles, were identified. Both profiles had a sweet taste and an astringent mouthfeel, however, the primary sensory profile is predominantly made up of “rooibos-woody”, “fynbos-floral” and “honey” aroma notes, while “fruity-sweet”, “caramel” and “apricot” aroma notes are the predominant sensory attributes of the secondary profile. The predictive value of the phenolic compounds of the infusions towards the taste and mouthfeel attributes (“sweet”, “sour”, “bitter” and “astringent”) was examined using different regression analyses, namely, Pearson’s correlation, partial least squares regression (PLS) and step-wise regression. Correlations between individual phenolic compounds and the taste and mouthfeel attributes were found to be significant, but low. Although a large sample set (N = 260) spanning 5 years (2009-2013) and two production areas (Western Cape and Northern Cape, South Africa) was used, no individual phenolic compounds could be singled out as being responsible for a specific taste or mouthfeel attribute. Furthermore, no difference was found between the phenolic compositions of the infusions based on production area, a trend that was also seen for the sensory characterisation of rooibos infusions. Sorting, a rapid sensory profiling method was evaluated for its potential use as a quality control tool for the rooibos industry. Instructed sorting was shown to successfully determine rooibos sensory quality, especially based on the aroma quality of the infusions. However, determining the quality of the infusion based on flavour quality was more difficult, possibly due to the low sensory attribute intensities. Categorisation of rooibos samples based on the two major aroma profiles i.e. the primary and secondary characteristic profiles, was achieved with uninstructed sorting. The potential of using sorting as a rapid technique to determine both quality and characteristic aroma profiles, was therefore demonstrated, indicating its relevance as another quality control tool to the rooibos industry.
AFRIKAANSE OPSOMMING: Gehaltebeheer hulpmiddels is as deel van hierdie studie vir die rooibosbedryf ontwikkel, hoofsaaklik om die sensoriese kwaliteit van rooibostee te bepaal. Aansienlike verskille is tussen monsters van dieselfde gehaltegraad opgemerk, primêr omdat daar in die wyer rooibosbedryf beperkte riglyne of prosedures in plek is om kwaliteitsverskille effektief te bepaal. Dit is as belangrik geag om gehaltebeheer hulpmiddels te ontwikkel om laasgenoemde probleem aan te spreek. Spesifieke gehaltebeheer hulpmiddels is dus vir hierdie studie ontwikkel en gevalideer deur die sensoriese eienskappe en fenoliese samestelling van rooibostee te analiseer. Beskrywende sensoriese analise (BSA) is gebruik om ‘n sensoriese wiel en leksikon vir die rooibosbedryf te ontwikkel en te valideer. Om alle moontlike produkvariasie te ondervang, is 230 gefermenteerde rooibos monsters afkomstig van die Noord-Kaap en Wes-Kaap areas in Suid-Afrika oor ‘n tydperk van drie jaar (2011-2013) verkry. Die aroma, geur, smaak en mondgevoel eienskappe wat met rooibos se sensoriese kwaliteit assosieer, is bevestig en uiteindelik gebruik om die sensoriese wiel te ontwikkel. Die gemiddelde intensiteit en persentasie voorkoms van elke eienskap is in die wiel ingesluit. Twee belangrike “karakteristieke” sensoriese profiele wat met rooibos geassosieer word, is geïdentifiseer, nl. die primêre en sekondêre sensoriese profiele. Tipies van beide sensoriese profiele is ‘n kenmerkende soet smaak en vrank mondgevoel, daarenteen bestaan die primêre sensoriese profiel hoofsaaklik uit "rooibos-houtagtige", "fynbos-blomagtige" en "heuning" aromas, terwyl "vrugtige-soet", "karamel" en "appelkoos" aromas die oorheersende sensoriese eienskappe van die sekondêre profiel is. Die korrelasie tussen die fenoliese verbindings en die smaak en mondgevoel eienskappe van rooibos ("soet", "suur", "bitter" en "vrankheid") is ondersoek met behulp van verskillende tipe regressieontledings, nl. Pearson se korrelasie, gedeeltelike kleinstekwadrate regressie (PLS) en stapsgewyse regressie. Korrelasies tussen individuele fenoliese verbindings en die smaak en mondgevoel eienskappe was laag, maar steeds betekenisvol. Alhoewel die uitgebreide stel monsters (N = 260) verteenwoordigend was van vyf oesjare (2009-2013) en twee produksiegebiede (Wes-Kaap en Noord-Kaap, Suid-Afrika), kon geen individuele fenoliese verbindings uitgesonder word as betekenisvolle voorspellers van spesifieke smaak of mondgevoel eienskappe nie. Verder is daar ook geen verskil tussen die verskillende produksie-areas wat betref fenoliese samestelling gevind nie. Soortgelyke resultate is bevind vir die sensoriese karakterisering van rooibostee. Sortering, 'n vinnige sensoriese profileringsmetode, is geëvalueer vir sy potensiële gebruik as 'n gehaltebeheer hulpmiddel vir die rooibosbedryf. Gestrukteerde sortering was suksesvol om rooibos se sensoriese kwaliteit, veral die algemene aroma kwaliteit van rooibos, te bepaal. Hierdie profileringsmetode was egter nie so suksesvol om rooibos se algemene geur, smaak en mondgevoeleienskappe te bepaal nie. Hierdie tendens kan moontlik toegeskryf word aan die betekenisvolle laer intensiteite van laasgenoemde sensoriese eienskappe. Die kategorisering van die rooibos monsters op grond van hul karakteristieke primêre en sekondêre sensoriese profiele is suksesvol deur middel van ongestrukteerde sortering bepaal. In die geheel gesien is die potensiaal van die sorteringstegniek as ‘n vinnige metode om die algemene sensoriese kwaliteit, asook die karakteristieke aroma profiele van rooibos te bepaal, dus bewys. Hierdie vinnige sensoriese profileringstegniek hou dus besliste voordele in vir die rooibosbedryf as dit kom by sensoriese gehaltebeheer.

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Cottone, Elyse. "Use of natural antioxidants in dairy and meat products : a review of sensory and instrumental analyses." Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/2267.

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Lee, Jeehyun. "Green Tea : flavor characteristics of a wide range of teas including brewing, processing, and storage variations and consumer acceptance of teas in three countries." Diss., Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1700.

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Sangaletti, Naiane. "Estudo da vida útil do queijo Minas frescal disponível no mercado." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-19102007-100720/.

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O queijo Minas frescal é um produto muito perecível e de curta duração. É necessário boas práticas de higienização durante sua produção e condições de armazenamento adequado para evitar a contaminação de microrganismos patogênicos e deteriorantes. Este trabalho teve por objetivo avaliar a vida útil do queijo Minas frescal durante o período de 30 dias armazenado a 4°C, através de análises sensoriais, microbiológicas e físico-químicas. Foram selecionadas seis marcas de queijo Minas frescal com registro no Serviço de Inspeção Federal (SIF), comercializados em supermercados de Piracicaba/SP até ser encontrado um produto dentro dos padrões da legislação vigente (BRASIL, 2001). O queijo selecionado foi adquirido direto do próprio lacticínio. As análises foram realizadas nos períodos de 1, 10, 20 e 30 dias após a fabricação do produto em três diferentes lotes denominados A, B e C. A contagem da população de microrganismos psicrotróficos totais, psicrotróficas proteolíticos, psicrotróficas lipolíticos, bactérias lácticas assim como de bactérias mesófilas totais apresentaram constante aumento mostrando crescimento de 8,50; 8,04; 8,30; 6,05 e 7,7 log UFC/g, respectivamente. Apenas do 30º dia do lote C o produto apresentou-se impróprio para o consumo com 1,7x104 NMP/g de Escherichia coli. Observou-se a redução do pH de 6,66 a 5,85 (0,81) e o aumento do ácido láctico de 0,044 a 0,07% (0,026%). O teor de gordura do queijo foi de 21,3% não sendo observado a sua redução. A quantidade de ácidos graxos livres foram determinados pela lipólise a qual aumentou em 0,22 mg KOH/g de gordura juntamente com a evolução dos microrganismos lipolíticos. A proteína variou de 21,30% a 22,10% sem diferença estatística significativa. A análise sensorial realizada pelo teste de aceitação através da escala hedônia teve entre 6,5 a 7,5 como pontuação o que indica que os julgadores gostaram ligeiramente e gostaram moderadamente do produto respectivamente durante o período de 30 dias. Conclui-se que o desenvolvimento das bactérias mesófilas, psicrotróficas totais, psicrotróficas proteolíticas, psicrotróficas lipolíticas e bactérias lácticas tem crescimento constante no queijo mesmo sob refrigeração levando este a se deteriorar com o passar do tempo. Da mesma forma o aumento significativo da acidez e de ácidos graxos livres. Apesar do aumento dos microrganismos e as alterações químicas o produto não teve mudanças sensoriais quanto aos atributos aparência, cor, odor, sabor e textura perante os dias de armazenamento. Uma vez que o queijo seja produzido sob ótimas condições higiênico sanitárias, ele é capaz de atingir o período de 30 dias de vida útil quando mantido a 4° C.
The Minas fresh cheese is very perishable product and its a short shelf life. Good practical of hygienic condition is necessary during its production and adjusted storage to prevent the proliferation of pathogenic and damage microorganism. This work had the objective evaluating the shelf life of the Minas fresh cheese for 30 days storaged at 4°C, through sensorial analyses, microbiological and physic-chemistries. Six marks of Minas fresh cheese commercialized in supermarkets in city Piracicaba/SP were selected, those are registered in Serviço de Inspeção Federal (SIF), but just one of them is inside of the standards of the current law (BRASIL, 2001). The select cheese was acquire direct of the Factory Dairy. The analyses were carried out in the periods of 1, 10, 20 and 30 days after the manufacturing of the product in the three different lots named A, B and C. The counting of the population of psychrotrophic microorganism total, psychrotrophic proteolytic, psychrotrophic lipolytic, lactic acidy bacteria as well as of mesophilic bacteria pesent constant increase showing growth of 8,50, 8,04, 8,30, 6,05 and 7,7 log UFC/g, respectively. On the 30th day of the lot C the product showed improper for the consumption with 1,7x104 NMP/g de Escherichia coli. It was observed a reduction of pH of 6,66 the 5,85 (0,81) and the increase of the lactic acidy of 0,044 the 0,07% (0,026%). The content of the cheese fat was 21,3% therefore its reduction wasn't observed. The amount of free fatty acid was determined by lipolysis which increased in 0,22 mg KOH/g of fat together with the evolution of the lipolytics microorganisms. The protein varied from 21,30% to 22,10% without difference significant statistics. The sensorial analysis carried through by the test of acceptance out the hedônic scale had punctuation between 6,5 the 7,5 what it indicates that the judges liked slightly and moderately respectively during the period of 30 days. The conclusion is that the development of the mesophilic bacteria, total psychrotrophic microorganism total, psychrotrophic proteolytic, psychrotrophic lipolytic and lactic acidy bacteria has constant growth in the cheese under refrigeration taking it this if to spoil with passing of the time. In the same way the significant increase of the acidity and free fatty acid. Despite of the increase of the microorganisms and the chemical alterations the product did not have sensorial changes how much to the attributes appearance, color, odor, flavor and in the presence the storage days. A time that the cheese is produced under excellent sanitary conditions hygienical, it is capable to reach the period of 30 days of shelf life when kept 4° C.

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