Готові списки джерел за темами / Sensory characterization of cheeses

Добірка наукової літератури з теми "Sensory characterization of cheeses"

Автор: Grafiati

Опубліковано: 11 травня 2022

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Статті в журналах з теми "Sensory characterization of cheeses":

Pisano, M. Barbara, M. Elisabetta Fadda, Maura Deplano, Arianna Corda, Maddalena Casula, and Sofia Cosentino. "Characterization of Fiore Sardo cheese manufactured with the addition of autochthonous cultures." Journal of Dairy Research 74, no. 3 (April 30, 2007): 255–61. http://dx.doi.org/10.1017/s0022029907002464.

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This work evaluated the effect of adjunct autochthonous cultures on the chemical, microbiological and sensory characteristics of Fiore Sardo cheese during ripening. A total of twelve batches of cheeses were manufactured according to the technical Disciplinary of Fiore Sardo cheese, with and without different combinations of autochthonous strains isolated from the native microflora of artisanal Fiore Sardo. There were no significant differences in the cheese compositional parameters between experimental and control cheeses, but the addition of cultures led to a statistically significant decrease in pH values in experimental cheeses. The evolution of total mesophilic bacteria, total coliforms and lactic acid bacteria were significantly influenced by the addition of autochthonous cultures in most of the experimental cheeses. As for sensory characteristics, all the experimental cheeses reported significantly higher scores especially for shape, texture, interior openings, taste and aftertaste. This study demonstrated the beneficial effect of the addition of selected autochthonous cultures in accelerating the disappearance of undesirable flora and improving the typical sensory characteristics of the cheese, and confirmed the importance of ewes' milk as a source of technologically interesting strains that could be used to ensure a higher quality of artisanal cheese productions.

Nyamakwere, F., G. Esposito, K. Dzama, M. Muller, E. I. Moelich, and E. Raffrenato. "A Survey of Cheese from Small-Scale Artisanal Producers in Western Cape, South Africa." Journal of Food Quality 2021 (October 29, 2021): 1–9. http://dx.doi.org/10.1155/2021/3708786.

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The objective of this study was to assess cow milk cheese from small-scale producers in the Western Cape Province, South Africa. Forty cheeses were selected, and microbiological data of the samples were analyzed with age (1, 3, 6 months), cheese type (Cheddar, Gouda, other), and milk type (raw and pasteurized) as main factors. Rapid sensory characterization was done using the sorting technique. The results indicated that the available cheese types were diverse, with minority (20.0%) in the Gouda group followed by Cheddar (32.5%) and “other” (47.5%). Most of these cheeses (45%) were aged three months and produced using pasteurized milk (92.5%). Five cheese samples did not meet the European Union standards for coliforms, and four samples tested positive for Escherichia coli. Sensory analysis results showed a clear differentiation between mature and young cheese. In conclusion, the current market presents more diverse milder cheeses, and there is a need to follow proper hygiene protocols to reduce cross-contamination.

Cagno, Raffaella Di, R. Evan Miracle, Maria De Angelis, Fabio Minervini, Carlo G. Rizzello, Mary Anne Drake, Patrick F. Fox, and Marco Gobbetti. "Compositional, microbiological, biochemical, volatile profile and sensory characterization of four Italian semi-hard goats' cheeses." Journal of Dairy Research 74, no. 4 (October 26, 2007): 468–77. http://dx.doi.org/10.1017/s0022029907002804.

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Four semi-hard Italian goats' milk cheeses, Flor di Capra (FC), Caprino di Cavalese (CC), Caprino di Valsassina (CV) and Capritilla (C), were compared for compositional, microbiological, biochemical, volatile profile and sensory characteristics. Mean values for the gross composition in part differed between cheeses. At the end of ripening, cheeses contained 7·98−8·51 log10 cfu/g of non-starter lactic acid bacteria. Lactobacillus paracasei, Lb. casei and Lb. plantarum were dominant in almost all cheeses. As shown by the Principal Component Analysis of RP-FPLC data for the pH 4·6-soluble fractions and by the determination of free amino acids, secondary proteolysis of CC and CV mainly differed from the other two cheeses. A total of 72 volatile components were identified by steam distillation-extraction followed by gas chromatography-mass spectrometry. Free fatty acids and esters qualitatively and quantitatively differentiated the profile of CV and CC, respectively. The lowest concentrations of volatile components characterized FC. Descriptive sensory analysis using 17 flavour attributes was carried out by a trained panel. Different flavour attributes distinguished the four goats' cheeses and relationships were found with volatile components, biochemical characteristics and technology.

Fusco, Vincenzina, Grazia Quero, Palmiro Poltronieri, Maria Morea, and Federico Baruzzi. "Autochthonous and Probiotic Lactic Acid Bacteria Employed for Production of “Advanced Traditional Cheeses”." Foods 8, no. 9 (September 13, 2019): 412. http://dx.doi.org/10.3390/foods8090412.

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Microbial characterization of two Italian traditional cheeses, Giuncata and Caciotta Leccese, was carried out, with the aim to isolate autochthonous bacterial strains to be used as starters to improve and standardize the quality of these cheeses. More than 400 bacterial isolates were found, using PCR-based identification, to belong to 12 species of the Streptococcus, Lactococcus, Lactobacillus, and Leuconostoc genera. The dominant strains were screened for antagonistic activity against pathogenic and spoilage bacteria and exopolysaccharide production, acidification, and proteolytic activity. Since Streptococcus macedonicus was found to be the most prevalent lactic acid bacteria species present in milk and in both types of cheese, the best performing strain of this species was successfully used, alone or in combination with a selected autochthonous Lactococcus lactis strain, in pilot-scale productions of Giuncata and Caciotta Leccese cheeses, respectively. The combined inoculums of selected autochthonous strains positively influenced the sensory characteristics of both Giuncata and Caciotta cheeses. Finally, the selected autochthonous cultures were enriched with a potentially probiotic Lactobacillus rhamnosus strain and successfully used in pilot-scale productions of these traditional cheeses. To the best of our knowledge, this is the first study reporting the use of an autochthonous S. macedonicus strain as a starter for the production of cheeses with added probiotics. In addition, the identification of the probiotic strain in the feces of healthy volunteers fed with the advanced traditional cheese proved its effectiveness as a carrier for the delivery of probiotics to the human body.

Bara-Herczegh, Ottília, József Csanádi, and Sándor Barakonyi. "Investigation on the texture of cream cheese with different methods." Analecta Technica Szegedinensia 7, no. 1-2 (January 24, 2013): 5–9. http://dx.doi.org/10.14232/analecta.2013.1-2.5-9.

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Rheological characterization of cheeses, especially processed cheeses is very important, because the quality is determined mainly by the texture properties, and the technology and the storage conditions have significant impact on the required texture. Rheological and texture properties are mainly affected by the chemical composition and the type and quantity of the processing conditions. After production the structure is going through of major changes during cooling period and the storage, so a description of knowledge well-defined circumstances, using the parameters may provide useful additional information to the qualification. The structure formation of the final product is also useful feed-back information for the manufacturer.Different type the Sole-Mizo Co. produced processed cheeses (nature and ham flavoured) were investigated by sensory and rheological methods (texture analyses and flow behaviour). The gross composition and the quality according to the sensory test met with the requirements, their quality were located in good and excellent category. The texture of samples was studied by Texture Analyser QTS 25. The nature cheeses were investigated in the total shelf-life according to a programme, the ham flavoured samples only during a shorter period. We determined the hardness value dependence versus shelf-life. The hardness can be a useful parameter in the qualification of cream cheese. The flow behaviour of ham favoured samples was investigated by viscometer at different temperature. The apparent viscosity changed with the temperature. Flow curves showed a same character as the typical non-Newtonian pseudo plastic fluids. It was created a consistency index (as a rheological parameter) and its changes can be associated whit with temperature induced changes in the structure of processed cheeses.

Wilhelm, C. M., A. Goldman, and T. A. Watts. "Sensory Evaluation and Characterization of Imported and Domestic Gouda Cheeses." Canadian Institute of Food Science and Technology Journal 18, no. 3 (September 1985): xli. http://dx.doi.org/10.1016/s0315-5463(85)71886-x.

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Wilhelm, C. M., and T. A. Watts. "Sensory Evaluation and Characterization of Imported and Domestic Havarti and Swiss Cheeses." Canadian Institute of Food Science and Technology Journal 19, no. 4 (October 1986): xliii. http://dx.doi.org/10.1016/s0315-5463(86)71577-0.

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Lashkari, Hannan, Mohammad Javad Varidi, Mohammad Hadi Eskandari, and Mehdi Varidi. "Effect of Pomegranate Juice on the Manufacturing Process and Characterization of Feta-Type Cheese during Storage." Journal of Food Quality 2020 (November 28, 2020): 1–11. http://dx.doi.org/10.1155/2020/8816762.

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The present research aimed to produce Fruit Feta-type cheese and investigate the effects of pomegranate juice on the manufacturing process and characterization of Feta-type cheese during storage. In order to produce Feta-type cheese with pomegranate juice, part of the milk was replaced with pomegranate juice. Therefore, it was necessary to produce Feta-type cheese with whey-less method, which is a good substitute for ultrafiltrated cheese. Initially, whey-less Feta-type cheese was produced. The formula was optimized based on the physicochemical characteristics of the marketed ultrafiltrated Feta cheeses. At the optimal point, the amount of cream, MPC, WPC, and fresh milk were 45.6, 11.7, 2.7, and 40%, respectively. Whey-less Feta-type cheese with these ratios was produced and the effects of different levels of pomegranate juice (0, 5, 10, 15, and 20%) on its physicochemical, textural, microbial, and sensorial properties during 60 days of storage were studied. The results showed that pomegranate juice increased acidity, total phenol, anthocyanin, DPPH inhibition, and a ∗ value, and reduced the pH, peroxide value, thiobarbituric acid (TBA), proteolysis, lipolysis, and L ∗ and b ∗ values. Adding pomegranate juice to cheese reduced all of the textural indices except the adhesiveness. Sensory evaluation of the samples showed that the sample containing 20% of pomegranate juice had a higher score and was selected as the best sample.

Loffi, Cecilia, Elena Bortolazzo, Anna Garavaldi, Valeria Musi, Paolo Reverberi, Gianni Galaverna, Stefano Sforza, and Tullia Tedeschi. "Reduction in the Brining Time in Parmigiano Reggiano Cheese Production Minimally Affects Proteolysis, with No Effect on Sensory Properties." Foods 10, no. 4 (April 3, 2021): 770. http://dx.doi.org/10.3390/foods10040770.

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Brine soaking is one of the most important steps in the production of Parmigiano Reggiano cheese, since it determines the amount of salt in the final product. Reduction in salt in Parmigiano Reggiano cheese might be important for improving its nutritional profile, but it could affect the manufacturing processes by altering proteolysis and consequently the product quality. In this study, for the first time, salt reduction was explored at the industrial level on real cheese samples manufactured in a local dairy. In particular, 20 wheels were produced with conventional (18 days, 10 wheels) and shorter (12 days, 10 wheels) brining steps. In every group, wheels were studied at two different ripening times, 15 and 30 months. A shorter brining time resulted in an average 12% decrease in salt content. A full characterization of free amino acids and peptides was performed by LC-MS on all samples. Free amino acids and peptides, as expected, increased with ripening, due to proteolysis, with samples having low salt content showing a slightly faster increase when compared to standard ones, hinting to a slightly accelerated proteolytic process. Nonetheless, low-salt and conventional cheeses shared similar sensory profiles at both ripening times.

Callon, Cécile, Liliane Millet, and Marie-Christine Montel. "Diversity of lactic acid bacteria isolated from AOC Salers cheese." Journal of Dairy Research 71, no. 2 (May 2004): 231–44. http://dx.doi.org/10.1017/s0022029904000159.

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The objective of this work was to describe the diversity of lactic acid bacteria in traditional raw milk Salers cheeses at the species and strain levels. The characterization of 381 strains isolated during ripening and various strain collections was investigated using physiological analysis and molecular techniques: Rep-PCR, species and genus specific amplifications and the sequence analysis of 16S rDNA for strain typing and taxonomic identification. The strains belonged to Lactobacillus plantarum, Lactobacillus paracasei, Lactococcus lactis, Lactococcus garviae, Enterococcus faecalis, Enterococcus faecium, Leuconostoc mesenteroides, Leuconostoc pseudomesenteroides, Streptococcus salivarius, Streptococcus millieri, Streptococcus macedonicus and Pediococcus pentosaceus. A wide phenotypic and genomic heterogeneity was observed within the different species (Lactobacillus plantarum, Lactobacillus paracasei and Leuconostoc mesenteroides) according to the origin and the time of ripening. The natural microflora was different from strain collection and each method must be combined to identify and characterize natural microflora. This study revealed the low selectivity of selective media used for the isolation of different groups of lactic acid bacteria except the Facultatively Heterofermentative lactobacilli medium selecting mesophile lactobacilli and SB medium selective for Enterococcus. The study reveals, for the first time, the microbial lactic acid bacteria community of Salers cheese and its diversity. A better knowledge of microbial flora will be useful to improve understanding of sensory quality of cheeses.

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Дисертації з теми "Sensory characterization of cheeses":

Saltaji, Sabrina. "Étude de l’apport de flores microbiennes issues du lait cru, purifiées par le procédé Bionatif®, appliquées à une production fromagère." Thesis, La Rochelle, 2020. http://www.theses.fr/2020LAROS033.

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Les ferments lactiques sont considérés comme un levier important de l’innovation pouvant apporter à la matrice fromagère de nouvelles propriétés organoleptiques, sensorielles et nutritionnelles. Cette thèse a eu pour sujet d’étude le procédé breveté Bionatif® qui purifie le lait cru de ses flores d’hygiène et d’altération de façon à restituer au fromager un ferment fonctionnel, composé d’une diversité bactérienne intra-spécifique propre au terroir de collecte (ferment indéfini). Ce travail s’est articulé autour de deux objectifs : i) caractériser la diversité des ferments indéfinis et étudier leur potentiel métabolique, ii) étudier l’expression des ferments en technologie fromagère pâte molle. Une diversité intra-spécifique des ferments indéfinis étudiés a été mise en évidence puisque plusieurs variants de L. lactis ont été découverts. Des isolats L. lactis du ferment indéfini présentaient des propriétés métaboliques supérieures et diversifiées notamment via l’expression de leur métabolisme des sucres (D-xylose, D-tagatose, etc.). Ce résultat a été confirmé par l’étude comparative de leur génome et pourrait être lié à leur origine environnementale. Les isolats L. lactis possèderaient également des ilots CRISPR-Cas particulièrement riches qui pourraient leur conférer une résistance accrue aux bactériophages. De plus, un potentiel antimicrobien a phénotypiquement été observé puis confirmé via l’étude génomique. En technologie fromagère pâte molle, la comparaison entre des ferments définis, conçus en conditions de laboratoire, et des ferments indéfinis, issus du procédé Bionatif®, a démontré que plus le consortium bactérien du ferment était complexe et diversifié, meilleures étaient les propriétés sensorielles et rhéologiques du fromage
Starter cultures confer enhanced properties to improve organoleptic, sensory and nutritional attributes upon the cheese matrix. The subject of this PhD project was the patented Bionatif® process. That process purifies raw milk from hygiene and spoilage microflora. Then, it restores a functional Undefined Mixed Starter Culture (UMSC) to the cheesemaker. That unique UMSC is composed of an intra-specific bacterial diversity specific to the terroir where the raw milk is collected.This work fixed two goals: i) to characterize the diversity of the UMSC and study their metabolic potential, ii) to study the expression of the UMSC in soft cheese technology. The UMSC intra-specific diversity study highlighted some bacterial variants of the L. lactis species. UMSC's L. lactis isolates showed superior and diversified metabolic properties through the expression of their sugar metabolism (D-xylose, D-tagatose, etc.). A comparative genome study confirmed this result and could link these metabolic properties to an environmental origin. L. lactis isolates also possess rich CRISPR-Cas clusters. These clusters could confer them a high resistance against bacteriophages. Besides, an antimicrobial potential has been phenotypically observed and then confirmed through genomic studies. In soft cheese technology, the comparison between defined starter cultures designed under laboratory conditions and UMSC from the Bionatif® process demonstrated that the more complex and diversified the bacterial consortium of the UMSC, the better the sensory and rheological properties of the cheese

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.

Štouračová, Anna. "Vliv podmínek skladování na obsah aromaticky aktivních látek v tavených sýrech." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216433.

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The aim of this diploma thesis was to monitor influence of storage conditions (temperature and time) on content of aroma substances in sterilized processed cheeses and also on their flavour. The part of cheeses was stored at 6°C, second part at room temperature 23 °C and third part at 40 °C. Processed cheeses were produced by Madeta, a. s., sterilized at 117 °C 20 min. The analysis was made at regular intervals, cheeses stored 16 and 23 months were analysed in this work. The aroma compounds were isolated by SPME and subsequently identified and quantified by gas chromatography. In total 37 aroma compounds were identified and quantified, 7 aldehydes, 7 ketones, 6 acids, 12 alcohols and 5 esters. Total content of aroma compounds increases with higher storage temperature. The time of storage has also influence on content of aroma compounds, we may say, that content is increasing, although sharp growth was registered only after 23 months, namely in the thermostat. Simultaneously sensory analysis of cheeses was made. Ranking test and evaluation using scale were used. Cheeses from a fridge were always evaluated as the best in all categories. Cheeses stored at room temperature were evaluated worse and cheeses from thermostat were the worst. So it is apparent, that high temperature supports undesirable chemical changes in cheeses and certainly is related to their flavour.

Quiñones, Patricia Maria. "Characterization of exocytosis in vertebrate sensory hair cells." Diss., Restricted to subscribing institutions, 2008. http://proquest.umi.com/pqdweb?did=1581455091&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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Aldworth, Zane Nathan. "Characterization of the neural codebook in an invertebrate sensory system." Diss., Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/aldworth/AldworthZ1207.pdf.

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Dintner, Sebastian. "Characterization of a sensory complex involved in antimicrobial peptide resistance." Diss., Ludwig-Maximilians-Universität München, 2014. http://nbn-resolving.de/urn:nbn:de:bvb:19-176173.

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In their habitats, microorganisms are often in competition for limited nutrients. In order to succeed, many Gram-positive bacteria resort to production of peptide antibiotics. Therefore, resistance mechanisms against these compounds are essential. The first step of ensuring survival is the perception of the harmful drugs and mediation of resistance against it. In recent years, a group of ABC-transporters have been recognized as important resistance determinate against antimicrobial peptides. The expression of these transporters is generally regulated by a two-component system, which in most cases is encoded next to the transporter. Together they are described as detoxification modules. The permeases of the transporters are characterized by a large extracellular domain, while the histidine kinases lack an obvious input domain. One of the best understood examples is the BceRS-BceAB system of Bacillus subtilis, which mediates resistance against bacitracin, mersacidin and actagardine. For this system it was shown that the histidine kinase is not able to detect the substrate directly and instead has an absolute requirement for the transporter in stimulus perception. This describes a novel mode of signal transduction in which the transporter is the actual sensor and therefore regulates its own expression. To date, mechanistic details for this unique mode of signal transduction remain unknown. Several other examples have been described for transport proteins that have acquired additional sensing or regulatory functions beyond solute transport, and these have been designated trigger transporters. For these bifunctional transporters a direct protein-protein interaction with membrane-integrated or soluble components of signal transduction relays has been postulated. However, for most sensor/co-sensor pairs, conclusive proof of such an interaction is lacking, and so far little is known about the sites that might mediate contacts between the putative protein interfaces and how communication is achieved. Based on sequence and architectural similarities, we identified over 250 BceAB-like transporters in the protein database, which occurred almost exclusively in Firmicutes bacteria. To whether the regulatory interplay between the ABC transporter and the two-component system was a common theme in these antimicrobial peptide resistance modules, we carried out a phylogenetic study of these identified systems. We identified a clear coevolutionary relationship between transport permeases and histidine kinases. Furthermore, we identified conserved putative response regulator binding sites in the promoter regions of the transporter operons. Additionally, we were able to provide a tool to identify TCSs for transporters lacking a regulatory system in their genomic neighbourhood, which was based on the coclustering of histidine kinases and transporter permeases. These findings also suggested the existence of a sensory complex between BceAB-like transporters and BceS-like histidine kinases. To further investigate the signaling mechanism, we performed a random mutagenesis of the transport permease BceB with the aim to identify regions or residues within the transporter that are involved in signaling and/or resistance. With this approach we were able to identify mutations that affected either the ability for signaling or mediation of resistance. This showed a partial genetic separation of the two qualities, which could be achieved by single amino acid replacements. These results provide first insights into the signaling mechanism of the Bce system. In order to analyse the proposed communication between two-component system and ABC transporter, we further characterized their interactions by in vivo and in vitro approaches. We could demonstrate that the transporter BceAB is indeed able to interact directly with the histidine kinase. Because it was unknown how the signal perception by BceAB-type transporters occurs, we next analyzed substrate binding by the transporter permease BceB and could show direct binding of bacitracin by BceB. Finally, in vitro signal transduction assays indicated that complex formation with the transporter influenced the activity of the histidine kinase. In summary this thesis clearly shows the existence of a sensory complex comprised of BceRS-like two-component systems and BceAB-like ABC transporters and provides first functional insights into the mechanism of stimulus perception, signal transduction and antimicrobial resistance mechanism employed by these wide spread detoxification systems against antimicrobial peptides.
Um sich in solch hart umkämpften Habitaten wie dem Boden zu behaupten sind Bakterien dazu übergegangen Antibiotika zu produzieren, um das Wachstum der Konkurrenz einzudämmen. Eine Gruppe solcher Substanzen sind antimikrobielle Peptide, die von Gram-positiven Bakterien produziert werden. Zum Schutz vor Peptidantibiotika haben Gram-positive Bakterien eine Vielzahl verschiedener Resistenzmechanismen entwickelt. Den effizientesten Resistenzmechanismus gegen Peptidantibiotika stellt eine Gruppe ATP-abhängiger ABC-Transporter dar. Diese Transporter weisen einen besonderen Transmembranaufbau auf. Sie bestehen aus zehn Transmembranhelices und einer großen extrazellulären Domäne. Die Expression dieser Transportergruppe wird durch ein Zweikomponentensystem reguliert. Die Histidinkinase besitzt ebenfalls einen ungewöhnlichen Transmembranaufbau, da sie keine offensichtliche Bindedomäne besitzt. Zusammen bilden der Transporter und die Histidinkinase ein Resistenzmodul gegen Peptidantibiotika, das in Firmicutes weit verbreitet ist. Eines der am besten verstandenen Systeme ist das BceRS-BceAB System in Bacillus subtilis. Dieses System vermittelt Resistenz gegen Bacitracin, Actagardin und Mersacidin. Für dieses System konnte gezeigt werden, dass die Histidinkinase BceS alleine nicht in der Lage ist, auf Bacitracin zu reagieren, sondern stattdessen für die Reizwahrnehmung und die Vermittlung der Resistenz auf den Transporter BceAB angewiesen ist. Der Transporter reguliert somit eine eigene Produktion. Wie der Resistenzmechanismus in diesem System genau funktioniert konnte bisher aber noch nicht hinreichend geklärt werden. Dass Transporter neben ihrer Funktion Substrate über eine Zellmembran zu transportieren auch an der Reizwahrnehmung und der Antwortregulation beteiligt sein können, ist in unterschiedlichsten Beispielen beschrieben worden. Um die Signalweiterleitung an membranständige oder zytoplasmatische Komponenten des Signalwegs gewährleisten zu können, müssen diese miteinander interagieren, zum Beispiel durch direkte Protein-Protein Interaktionen. Bisher konnte jedoch für viele solcher Sensorkomplexe keine endgültige Erklärung für solch eine Interaktion dargestellt werden. Basierend auf einer Datenbankanalyse konnten über 250 BceAB-artige Transporter identifiziert und ein Großteil davon einer BceS-artigen Histidinkinase zugeordnet werden. Durch eine phylogenetische Studie konnte weiterhin gezeigte werden, dass BceRS-artige Zweikomponentensysteme und BceAB-artige Transporter in Firmicutes Bakterien weit verbreitet sind und sich über Ko-Evolution gemeinsam zu Resistenzmodulen gegen Peptidantibiotika entwickelt haben. Dazu konnte eine konservierte Antwortregulator-Bindestelle in den Promoter Regionen der Transporteroperons bestimmt werden. Zudem war es möglich aufgrund dieser Klassifizierung für diejenigen Permeasen ohne ein benachbartes Zweikomponentensystem anhand der Genomsequenz ein mögliches Regulationssystem zuzuordnen. Diese Erkenntnisse unterstützten die Vermutung über einen sensorischen Komplex zwischen BceS-ähnlichen Histidinkinasen und BceAB-ähnlichen ABC Transportern. In einer weiteren Studie konnten mittels zufälliger Mutagenese der Transporterpermease BceB Aminosäurereste identifizierte werden, die an der Signalweiterleitung und/oder Resistenzvermittlung beteiligt waren. Durch einige der eingefügten Mutationen wurde nur die Signalweiterleitung bzw. nur die Resistenz beeinträchtigt. Dies spricht dafür, dass eine partielle genetische Trennung der Aufgaben des Transporters möglich ist. Hierdurch konnten erste wichtige Einblicke in den Signalweiterleitungsmechanismus des Bce-Systems gewonnen werden. Um die vorgeschlagene Kommunikation zwischen Zweikomponentensystem und ABCTransporter weiterführend zu untersuchen, wurden Interaktionsstudien durchgeführt. Die auf in vitro und in vivo Studien basierenden Ergebnisse konnten eine direkte Interaktion zwischen BceS und BceAB darstellen. Darüber hinaus konnten wir in dieser Arbeit durch eine Oberflächenresonanz- Spektroskopie zum ersten Mal zeigen, dass die Transporterpermease Bacitracin direkt und spezifisch bindet. Außerdem konnte durch eine in vitro Rekonstruktion des Signalwegs im Bce-System gezeigt werden, dass die Aktivität der Histidinkinase durch die Anwesenheit des Transporters beeinflusst wird. Zusammenfassend zeigt die vorliegende Arbeit direkte Hinweise, dass BceRS-artige Zweikomponentensysteme und BceAB-artige ABC-Transporter zusammen einen sensorischen Komplex für Peptidantibiotika bilden. Dies wird unterstützt durch erste funktionelle Einblicke in die Mechanismen der Reizwahrnehmung und Signalweiterleitung in diesen in Firmicutes Bakterien weit verbreiteten Resistenzsystemen.

Piras, Simone. "Volatile and sensory characterization of white wines from minority grapes varieties." Master's thesis, ISA, 2019. http://hdl.handle.net/10400.5/19567.

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Bord, Cécile. "Impact du traitement thermique sur les perceptions sensorielles et les préférences des consommateurs pour les fromages à pâte persillée : cas de la fourme d'Ambert." Thesis, Clermont-Ferrand 2, 2015. http://www.theses.fr/2015CLF22567/document.

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Les fromages d’«Appellation d’Origine Protégée» (AOP) présentant un cahier des charges précis sont garants d’un savoir-faire, d’une tradition et d’un lien avec le terroir et sont également reconnus pour leurs qualités organoleptiques. Malgré une bonne implantation au niveau du marché et une consommation non négligeable, certains fromages AOP voient leurs ventes baisser. Pour dynamiser certains de ces fromages, notamment les fromages à pâte persillée, leur utilisation comme « fromages ingrédients » s’avérerait pertinente. Ce nouveau segment, très porteur pour les fromagesindustriels, consiste à les utiliser dans des préparations culinaires aussi bien à chaud qu’à froid. L’objectif des travaux de cette thèse est de réaliser d’une part un focus sur les propriétés sensorielles des fromages à pâte persillée AOP du Massif central, induites par le chauffage et plus particulièrement de la Fourme d’Ambert, en étudiant les fractions solubles de ces fromages, d’un point de vue biochimique et sensoriel, et d’autre part de connaître les préférences des consommateurs vis-à-vis des fromages à chaud. Dans un premier temps, un screening sur le comportement à chaud de différentes catégories de fromages à pâte persillée a conduit à identifier des différences texturales et gustatives et de ce fait, à catégoriser les fromages selon leurs aptitudes culinaires. Ce positionnement sensoriel a ainsi permis de sélectionner un « fromage modèle » : la Fourme d’Ambert. Dans une seconde phase, l’étude des fractions solubles a confirmé sa contribution relative dans la perception gustative des fromages à pâte persillée. Toutefois, aucune différence sensorielle n’est observée sur les fractions suite au traitement thermique malgré quelques différences sur la teneur de certains composés sapides. Enfin, la dernière phase a consisté à identifier les préférences des consommateurs vis-à-vis de la Fourme d’Ambert à froid et à chaud. Quelle que soit la température, le fromage est bien apprécié par les consommateurs. La segmentation des consommateurs révèle des perceptions différentes selon trois groupes : un groupe avec des préférences pour des fromages très typés, à l’inverse, un groupe ayant une attirance pour les fromages ayant des flaveurs moins prononcées et un dernier, axé sur les préférences des fromages à chaud. Corrélées aux profils sensoriels, aux commentaires libres des consommateurs et à leurs attentes, certaines variables sensorielles ou comportementales ont pu expliquer ces différences de préférences. Ces résultats montrent l’intérêt de l’usage de certains fromages à pâte persillée AOP en tant que « fromages ingrédients » présentant de bonnes aptitudes culinaires, par leurs propriétés fonctionnelles et gustatives. L’acceptation des fromages à chaud par les consommateurs renforce le fait que les fromages AOP peuvent être utilisés aussi bien à froid qu’à chaud, permettant ainsi l’innovation dans la filière
PDO cheeses through their specifications are recognized for a quality in relation to a geographical origin, technical know-how, and a typical gustative quality. Despite a good consumption of PDO cheeses, the marketed volumes decreased for most of them. In order to make them more attractive, some cheeses as Blue cheeses could be used as “cheeses ingredient”. Cheeses are usually consumed at the end of a meal but a new trend is emerging: cheeses are more and more used in culinary preparations, both hot (pizza, gratin, sauce) and cold (sandwiches, salads). The main objective of this study was to firstly highlight the impact of heating on sensory properties of French PDO Blue cheeses and more particularly Fourme d’Ambert. The water-soluble fraction which plays an important role in the favour of cheeses was secondly studied in order to evaluate the impact of heating on this extract. The last objective consisted in measuring the consumers liking towards cold and heated cheeses. Therefore, sensory and biochemical methods were performed to describe crude cheeses and liking. The first study highlighted the impact of heating on both textural properties and flavour of four PDO blue-type cheeses. The main results showed that PDO cheeses present different culinary properties and thus are compatible with a use into hot preparations. The first step allowed to select a model cheese: Fourme d’Ambert. The second step consisted in studying the impact of heating on the crude cheeses and on the water-soluble fraction. In parallel, the gross composition was performed on soluble fractions and cheeses according to heating treatment. Although no treatment difference was observed on the water-soluble fraction gustatory profile, a slight difference was showed on certain chemical constituents between the water-soluble extracts. The last step was focused on the consumers liking towards cold and heated cheeses. The results showed that cheeses were much appreciated whatever heating treatments highlighting a slightly preference towards heated cheeses. Moreover, 3 groups of consumers were formed based on different preferences. One group preferred heated cheeses while two others groups preferred cold cheeses. Consumers’ group preferences were explained by means of sensory profiles and open-ended questions responses.Finally, this study shows the opportunities of new culinary uses for Blue cheeses. Sensory methods application had allowed to provide detailed information on heating properties of blue cheeses. In addition, consumers’ acceptance reinforce that PDO cheeses can be used in cold or heated preparations

Cheng, Albert Wu. "Characterization of irx-1 transcription factor in C. elegans male sensory ray development /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?BIOL%202007%20CHENG.

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Chan, Wai Hung. "Characterization of mab-22 genetic pathway in male sensory ray assembly of caenorhabditis elegans /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?BIOL%202006%20CHAN.

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Varela, Paula, and Gaston Ares. Novel techniques in sensory characterization and consumer profiling. Boca Raton: CRC Press, 2014.

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1973-, Deibler Kathryn D., and Delwiche Jeannine 1967-, eds. Handbook of flavor characterization: Sensory analysis, chemistry, and physiology. New York: Marcel Dekker, 2004.

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Murray, E. Lee, and Veda V. Vedanarayanan. Motor and Sensory Disturbance. Edited by Karl E. Misulis and E. Lee Murray. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190259419.003.0004.

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Localization and characterization of motor and sensory deficits is often the first step in establishing a differential diagnosis of a neurologic presentation. This chapter discusses motor and sensory functions and deficits individually and collectively. The emphasis is on disorders commonly encountered in hospital practice.

Theerakulkait, Chockchai. Sweet corn germ lipoxygenase: Isolation, purification, characterization and involvement in off-aroma formation. 1994.

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Drake, Mary Anne. Characterization and analysis of milkfat sucrose polyesters and their incorporation as milkfat substitutes in reduced fat cheddar-type cheeses. 1992.

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Noordhof, Paul. Evaluative Perception as Response-Dependent Representation. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198786054.003.0005.

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One dimension of the controversy over whether evaluative properties are presented in perceptual content has general roots in the debate over whether perceptual content, in general, is rich or austere. This chapter argues that we need to recognize a level of rich non-sensory perceptual content, drawing on experiences of chicken sexing and speech perception, to capture what our experience is like and our epistemic entitlements. In both cases (and many others), we are not conscious of the precise perceptual cues that are the basis for discriminations and, thus, the characterization of the phenomenal content of such experiences must go beyond sensory properties. Nevertheless, this point is arguably insufficient to establish the perception of evaluative properties. Their representation requires the subject to respond in certain ways. The chapter discusses how this should go for the case of pain and then, in outline, for moral properties.

Частини книг з теми "Sensory characterization of cheeses":

Hnosko, Jonathan, Stephanie Clark, and Diane Van Hekken. "Latin American Cheeses." In The Sensory Evaluation of Dairy Products, 489–504. New York, NY: Springer US, 2008. http://dx.doi.org/10.1007/978-0-387-77408-4_16.

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Bett-Garber, Karen L. "Sensory Characterization." In Handbook of Meat, Poultry and Seafood Quality, 63–75. Oxford, UK: Blackwell Publishing Ltd., 2012. http://dx.doi.org/10.1002/9781118352434.ch5.

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de Renobales, M., M. Virto, and L. J. R. Barron. "7. Rennets and sensory characteristics of traditional cheeses." In Human Health Handbooks, 103–22. The Netherlands: Wageningen Academic Publishers, 2013. http://dx.doi.org/10.3920/978-90-8686-766-0_7.

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Sberveglieri, Veronica, Manohar P. Bhandari, Andrea Pulvirenti, and Estefania Núñez Carmona. "Grated Parmigiano Reggiano Cheese: Authenticity Determination and Characterization by a Novel Nanowire Device (S3) and GC-MS." In Sensors for Everyday Life, 229–43. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-47322-2_11.

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Bora, Nagamani. "Characterization of Actinomycetes from Smear Ripened Cheeses – A Polyphasic Approach." In Diversity, Dynamics and Functional Role of Actinomycetes on European Smear Ripened Cheeses, 51–101. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-10464-5_3.

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Licitra, Giuseppe, and Stefania Carpino. "The Microfloras and Sensory Profiles of Selected Protected Designation of Origin Italian Cheeses." In Cheese and Microbes, 151–65. Washington, DC, USA: ASM Press, 2014. http://dx.doi.org/10.1128/9781555818593.ch7.

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Ares, Gastón, and Ana Giménez. "New Trends in Sensory Characterization of Food Products." In Advances in Food Science and Nutrition, 321–59. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118865606.ch10.

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Fanger, P. O. "Sensory Characterization of Air Quality and Pollution Sources." In Eurocourses: Chemical and Environmental Science, 59–71. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-015-8088-5_6.

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Laffitte, Anni, Fabrice Neiers, and Loïc Briand. "Characterization of taste compounds: chemical structures and sensory properties." In Flavour, 154–91. Chichester, UK: John Wiley & Sons, Ltd, 2016. http://dx.doi.org/10.1002/9781118929384.ch7.

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Engel, Karl-Heinz. "Chemical and Sensory Characterization of Food Volatiles: An Overview." In ACS Symposium Series, 1–5. Washington, DC: American Chemical Society, 2001. http://dx.doi.org/10.1021/bk-2001-0794.ch001.

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Тези доповідей конференцій з теми "Sensory characterization of cheeses":

Wincheski, Buzz, John Simpson, Terryl Wallace, Andy Newman, Paul Leser, and Rob Lahue. "Electromagnetic characterization of metallic sensory alloy." In REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION: VOLUME 32. AIP, 2013. http://dx.doi.org/10.1063/1.4789226.

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Mares-Mares, Everardo, F�tima Luz Mar�a Herrera-Castillo, Jos� Eleazar Barboza-Corona, Ricardo Navarro-Mendoza, Ana Angelica Feregrino-P�rez, Maria Elena Sosa-Morales, and Maria Fabiola Le�n-Galv�n. "<i>Molecular characterization of primary and secondary lactoseric proteins of whey coming from different cheeses</i>Introduction." In 2017 Spokane, Washington July 16 - July 19, 2017. St. Joseph, MI: American Society of Agricultural and Biological Engineers, 2017. http://dx.doi.org/10.13031/aim.201701252.

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Tavakoli, M., A. Aziminejad, R. V. Patel, and M. Moallem. "Multi-sensory force/deformation cues for stiffness characterization in soft-tissue palpation." In Conference Proceedings. Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE, 2006. http://dx.doi.org/10.1109/iembs.2006.260292.

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Laroy, Wouter, Yumi Tagawa, Kazim A. Sheikh, and Ronald L. Schnaar. "CHARACTERIZATION OF DIFFERENT GD1a SPECIES IN HUMAN SENSORY AND MOTOR SPINAL ROOTS." In XXIst International Carbohydrate Symposium 2002. TheScientificWorld Ltd, 2002. http://dx.doi.org/10.1100/tsw.2002.463.

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Filip, Petr, and Tereza Moravkova. "On the relation between sensory attributes and rheological characterization of cosmetic products." In NOVEL TRENDS IN RHEOLOGY VII. Author(s), 2017. http://dx.doi.org/10.1063/1.4983002.

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Rutz, Adriano, Pascale Deneulin, Ivano Tonutti, Benoît Bach, and Jean-Luc Wolfender. "Untargeted chemical and sensory characterization of Swertia chirayita: a bitter case study." In GA – 69th Annual Meeting 2021, Virtual conference. Georg Thieme Verlag, 2021. http://dx.doi.org/10.1055/s-0041-1736968.

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Cornell, Stephen R., William P. Leser, Jacob D. Hochhalter, John A. Newman, and Darren J. Hartl. "Development and Characterization of Embedded Sensory Particles Using Multi-Scale 3D Digital Image Correlation." In ASME 2014 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/smasis2014-7608.

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A method for detecting fatigue cracks has been explored at NASA Langley Research Center. Microscopic NiTi shape memory alloy (sensory) particles were embedded in a 7050 aluminum alloy matrix to detect the presence of fatigue cracks. Cracks exhibit an elevated stress field near their tip inducing a martensitic phase transformation in nearby sensory particles. Detectable levels of acoustic energy are emitted upon particle phase transformation such that the existence and location of fatigue cracks can be detected. To test this concept, a fatigue crack was grown in a mode-I single-edge notch fatigue crack growth specimen containing sensory particles. As the crack approached the sensory particles, measurements of particle strain, matrix-particle debonding, and phase transformation behavior of the sensory particles were performed. Full-field deformation measurements were performed using a novel multi-scale optical 3D digital image correlation (DIC) system. This information will be used in a finite element-based study to determine optimal sensory material behavior and density.

Kishimoto, Norihito, Kana Iwata, Atsuhiko Utsumi, and Toshiyuki Yajima. "Sensory characterization of oils extracted from lacto-fermented olives using an electronic nose." In 2017 ISOCS/IEEE International Symposium on Olfaction and Electronic Nose (ISOEN). IEEE, 2017. http://dx.doi.org/10.1109/isoen.2017.7968851.

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KIM, SONGHUI, YOUNGWOON YOON, AHREUM CHOI, KWANGHWAN JUNG, KIEJIN LEE, BARRY FRIEDMAN, and TAKAYUKI ISHIBASHI. "OPTICAL CHARACTERIZATION OF SENSORY RHODOPSIN II THIN FILMS USING A NEAR-FIELD MICROWAVE MICROSCOPE." In Proceedings of the International Conference on ANDE 2007. World Scientific Publishing Company, 2008. http://dx.doi.org/10.1142/9789812790194_0124.

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Звіти організацій з теми "Sensory characterization of cheeses":

Lo, Yin-Cheung, Jacek A. Koziel, Lingshuang Cai, Steven J. Hoff, William S. Jenks, and Hongwei Xin. Simultaneous Chemical and Sensory Characterization of VOCs and Semi-VOCs Emitted from Swine Manure Using SPME and Multidimensional Gas Chromatography-Mass Spectrometry-Olfactometry. Ames (Iowa): Iowa State University, January 2007. http://dx.doi.org/10.31274/ans_air-180814-276.

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Rouseff, Russell L., and Michael Naim. Characterization of Unidentified Potent Flavor Changes during Processing and Storage of Orange and Grapefruit Juices. United States Department of Agriculture, September 2002. http://dx.doi.org/10.32747/2002.7585191.bard.

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Citrus juice flavor quality traditionally diminishes after thermal processing and continuously during storage. Our prior studies found that four of the five most potent off-aromas formed during orange juice storage had not been identified. The primary emphasis of this project was to characterize and identify those potent flavor degrading aroma volatiles so that methods to control them could be developed and final flavor quality improved. Our original objectives included: 1 Isolate and characterize the most important unidentified aroma impact compounds formed or lost during pasteurization and storage. 2. Determination of thiamine and carotenoid thermal decomposition and Strecker degradation pathways in model solutions as possible precursors for the unidentified off-flavors. 3. Evaluate the effectiveness of an "electronic nose" to differentiate the headspace aromas of from untreated and heat pasteurized orange and grapefruit juices. 4. Use model systems of citrus juices to investigate the three possible precursor pathways (from 2) for flavor impact compounds formed or lost during pasteurization or storage. RESULTS - The components responsible for citrus storage off flavors and their putative precursors have now been identified. Certain carotenoids (b-carotene) can thermally degrade to produce b-ionone and b-damascenone which are floral and tobacco smelling respectively. Our GC-O and sensory experiments indicated that b-damascenone is a potential storage off-flavor in orange juice. Thiamine (Vitamin B1) degradation produces 2-methyl-3-furan thiol, MFT, and its dimer bis(2- methyl-3-furyl) disulfide which both produce meaty, savory aromas. GC-O and sensory studies indicated that MFT is another storage off-flavor. Methional (potato aroma) is another off flavor produced primarily from the reaction of the native amino acid, methionine, and oxidized ascorbic acid (vitamin C). This is a newly discovered pathway for the production of methional and is more dominant in juices than the classic Maillard reaction. These newly identified off flavors diminish the flavor quality of citrus juices as they distort the flavor balance and introduce non-typical aromas to the juice flavor profile. In addition, we have demonstrated that some of the poor flavor quality citrus juice found in the market place is not only from the production of these and other off flavors but also due to the absence of desirable flavor components including several potent aldehydes and a few esters. The absence of these compounds appears to be due to incomplete flavor volatile restoration after the making of juice concentrates. We are the first to demonstrate that not all flavor volatiles are removed along with water in the production of juice concentrate. In the case of grapefruit juice we have documented which flavor volatiles are completely removed, which are partially removed and which actually increase because of the thermal process. Since more that half of all citrus juices is made into concentrate, this information will allow producers to more accurately restore the original flavor components and produce a juice with a more natural flavor. IMPLICATIONS - We have shown that the aroma of citrus juices is controlled by only 1-2% of the total volatiles. The vast majority of other volatiles have little to no direct aroma activity. The critical volatiles have now been identified. The ability to produce high quality citrus juices requires that manufacturers know which chemical components control aroma and flavor. In addition to identifying the critical flavor components (both positive and negative), we have also identified several precursors. The behavior of these key aroma compounds and their precursors during common manufacturing and storage conditions has been documented so manufacturers in Israel and the US can alter production practices to minimize the negative ones and maximize the positive ones.