Academic literature on the topic 'Sucrose content'
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Journal articles on the topic "Sucrose content"
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Kumar, Pushpa Chethan, S. Amutha, H. S. Oberoi, and S. Vellaikumar. "Quality evaluation of artificially sweetened millet flour incorporated pomegranate RTS beverage." Journal of Applied Horticulture 25, no. 01 (2023): 69–73. http://dx.doi.org/10.37855/jah.2023.v25i01.12.
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The study aimed to develop a pomegranate beverage by substituting sucrose with an artificial sweetener sucralose and incorporating germinated flour from foxtail and little millet to enhance nutritional quality. The developed beverage was analyzed for physicochemical, bioactive, and sensory parameters. The result showed that substituting 100 % sucrose with sucralose had less total soluble solid content. Total and reducing sugar content was significantly high in control samples compared to sucralose-added treatments. However, total polyphenols and antioxidant activity were 20 and 18.50 % less in sucralose treatments, respectively, compared to the control. Incorporating germinated millet flour did not significantly increase the bioactive compounds of the pomegranate beverage. Further, substituting sucrose with sucralose was not accepted organoleptically, however, there was no change in the taste due to the incorporation of germinated millet flours. Hence, the substitution of sucrose with sucralose depends on the fruit type in the preparation of RTS (Ready-to-serve) beverage and the incorporation of germinated millet flours depends on the concentration to enhance the bioactive compounds of the beverage.
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Wee, Chi-Do, Masatsugu Hashiguchi, Genki Ishigaki, et al. "Evaluation of seed components of wild soybean (Glycine soja) collected in Japan using near-infrared reflectance spectroscopy." Plant Genetic Resources: Characterization and Utilization 16, no. 2 (2017): 94–102. http://dx.doi.org/10.1017/s1479262116000472.
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AbstractSeed composition, including the protein, lipid and sucrose contents of 334 accessions of wild soybean (Glycine soja) collected in Japan, was evaluated using near-infrared reflectance spectroscopy (NIRS) technology. The distribution of protein, lipid and sucrose contents and correlations among these three classes of seed components were determined. Protein, lipid and sucrose levels ranged in accessions from 48.6 to 57.0, 9.0 to 14.3 and 1.24 to 3.53%, respectively. Average levels of protein, lipid and sucrose in the accessions were 54, 11 and 2.5%, respectively. High negative correlations were observed between the protein and lipid contents, and the protein and sucrose contents. Mean levels of the three constituents were compared among collection sites classified by climatic conditions. The total protein content of accessions from regions with a high annual mean temperature was high. The protein content of accessions from the II-1 region was higher than those from the III-3 region, and the sucrose content from the II-1 region was lower than those from regions III-2 and IV-3. The lipid content of plants from the II-1 region was lower than those from other regions, and the accessions in region II had a higher protein content and lower sucrose and lipid contents than the other regions. These results provide diverse and wide-ranged protein, lipid and sucrose contents information of Japanese wild soybean resources according to climatic region; thus, providing a foundation for the future development and selection of new soybean varieties with desired traits in global environmental changes.
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Forney, Charles F., and Breen Patrick J. "Sugar Content and Uptake in the Strawberry Fruit." Journal of the American Society for Horticultural Science 111, no. 2 (1986): 241–47. http://dx.doi.org/10.21273/jashs.111.2.241.
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Abstract Sucrose was not detected in developing fruit of ‘Brighton’ strawberry (Fragaria × ananassa Duch.) until 10 days after anthesis. Thereafter, its concentration increased rapidly but then declined as fruit became red ripe. The concentration of glucose and fructose were similar and higher than that of sucrose during early fruit growth and in ripe fruit. Uptake of 14C-sugars was followed in excised disks of cortical tissue from fruit 15–17 days old. The addition of CaCl2 was necessary to maintain tissue respiration. Sucrose uptake into tissue disks was nearly constant over 4 hr and had a pH optimum of 5.0. Kinetic analysis of sucrose uptake revealed both linear and saturable components. The kinetic characteristics of fructose uptake was similar to those for sucrose. Glucose, however, was taken up much more rapidly than either sucrose or fructose and only demonstrated saturation kinetics. The metabolic inhibitors NaCN (5 mM), dinitrophenol (DNP, 3 Mm) and carbonyl cyanide m-chlorophenyl hydrazone (CCCP, 100 μM) stimulated sucrose uptake 34%, 94%, and 54%, respectively. DNP eliminated the saturable component. Uptake of sucrose was inhibited by 36% with 10 μm DNP, 16% with 5 mM glucose, and 16% in a 100% N2 atmosphere. After incubation in 14C-sugars for 2 hr, about 90% of the label recovered from disks was in a neutral fraction. Half or more of this was in either glucose or fructose, depending upon the sugar fed. The distribution of 14C between glucose and fructose moieties of sucrose isolated from tissue fed (14C-fructosyl) sucrose indicated that a portion of the sucrose recovered underwent hydrolysis and randomization. Similar results were found with sucrose isolated from attached, whole fruit 8 hr after abraded leaves were fed labeled sugars. Results suggest that sucrose may be hydrolized prior to uptake into fruit tissue.
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Chenlo, F., R. Moreira, L. Chaguri, and M. D. Torres. "Note. Sugar, Moisture Contents, and Color of Chestnuts during Different Storage Regimes." Food Science and Technology International 15, no. 2 (2009): 169–78. http://dx.doi.org/10.1177/1082013208106321.
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Color, moisture and sucrose, glucose and fructose contents of chestnuts (Castanea sativa Mill.) at several initial states (whole and undried; whole, peeled, and partially air-dried, with or without prior sucrose treatment; peeled, broken, and undried or partially air-dried) were monitored for 11 months during storage under various conditions (unpacked, packed in plastic bags at ambient pressure, or vacuum packed) and temperature (at room temperature, 3°C or -18°C). Moisture content decreased considerably in all cases except in those of packed whole peeled chestnuts without sucrose treatment and stored at room temperature or 3°C. Chestnuts stored for 2 months in contact with the atmosphere had moisture contents of only ∼4% of their dry weight. After 4 months storage, sucrose content had fallen (in some cases to zero) in all samples except in broken chestnuts dried to a 2% moisture content and conventionally stored whole unpeeled chestnuts (in which sucrose content rose slightly). Glucose and fructose contents generally peaked after 1-2 months of storage, and by month 4 returned to initial or lower levels. Sugar content was hardly affected by initial moisture or sugar contents except when moisture content had been reduced to 2%. Color changes were least during storage in air or at 3°C.
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Inman-Bamber, N. G., P. A. Jackson, and M. Hewitt. "Sucrose accumulation in sugarcane stalks does not limit photosynthesis and biomass production." Crop and Pasture Science 62, no. 10 (2011): 848. http://dx.doi.org/10.1071/cp11128.
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Until now raw sugar has been the predominant commodity produced from sugarcane (Saccharum spp. hybrids) with the exception of Brazil where fermentable sugars are used to produce ethanol. Worldwide interest in renewable energy has focussed attention on total biomass production of ‘energy canes’ rather than sucrose yield alone. Clones selected for biomass tend to have high fibre contents derived from the wild type, S. spontaneum. It is possible that high fibre genotypes can produce higher biomass yields than high sucrose types due to feedback on photosynthesis either by sucrose or sucrose signalling compounds as proposed in several recent publications on feedback responses in sugarcane leaves. Up to 20 sugarcane clones with either high fibre or high sucrose content were grown in one field and three pot experiments to elucidate some of the processes from source to sink that could be responsible for high rates of biomass accumulation expected in high fibre clones. We were particularly interested in the possibility that clones with high sucrose content may have reduced photosynthesis as sucrose levels increased in upper internodes due to feedback mechanisms. Photosynthesis of whole plants and of single leaves decreased with crop development as much as 60% in some cases. Maintenance of photosynthesis was not associated with low content of sugars in leaves or in internodes. Sink strength for sucrose storage in the upper internodes was strong in both high fibre and high sucrose clones despite plants being grown for 12 months in conditions controlled to achieve high sucrose contents. Our data supported previous conclusions about localised feedback on photosynthesis by sugars accumulating in the leaf resulting in reduced photosynthesis of small segments of individual young leaves. However, whole-plant photosynthesis did not decline through the day indicating that older leaves may compensate for reduced photosynthesis in younger leaves in the afternoon. While photosynthesis declined with crop age and sucrose content increased we found no evidence to suggest that photosynthesis declined because sucrose content increased. An increase in biomass yield through breeding and selection may not necessarily result in reduced sucrose content and increased fibre content.
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GUO, Jian-Bin, Liang-Qiang CHENG, Wei-Tao LI, et al. "Correlation analysis of sucrose content with protein and oil content and QTL mapping of sucrose content in peanut." Acta Agronomica Sinica 49, no. 10 (2023): 2698–704. https://doi.org/10.3724/sp.j.1006.2023.24251.
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Gąsecka, Monika, Jerzy Stachowiak, Włodzimierz Krzesiński, Mikołaj Knaflewski, and Piotr Goliński. "Changes in Glucose, Fructose and Sucrose Contents in Storage Roots of Asparagus During Vegetation Period." Vegetable Crops Research Bulletin 69, no. 1 (2008): 145–54. http://dx.doi.org/10.2478/v10032-008-0029-9.
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Changes in Glucose, Fructose and Sucrose Contents in Storage Roots of Asparagus During Vegetation PeriodThe objective of the field experiment conducted during 2000-2002 was to determine changes in glucose, fructose and sucrose contents in storage roots of asparagus (Asparagus officinalisL.) cv.‘Thielim’during vegetation period. The aim of the study was also to estimate the correlation between yield and the content of carbohydrates. Sum of glucose, fructose and sucrose contents (GFS) and sucrose contents in storage roots of asparagus decreased at the beginning and increased at the end of harvest. Generally glucose and fructose for carbohydrate contents increased, while that of sucrose decreased. A possitive correlation was observed for sucrose and GFS between asparagus spears and storage roots (r=0.821 and r=0.641, respectively). A negative correlation between the yield of spears and glucose, sucrose and GFS contents in storage roots was found (r=0.595, r=0.624, r=0.794, respectively). Positive correlations were found between total yield during harvest and year of cropping, average GFS content in storage roots during harvest, sum of radiation during harvest, while negative correlation between total yield and sum of average daily air temperature during harvest was found.
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Shi, Yao, Jishun Li, and Yuanliang Duan. "Sugar substitute test applications for bakery products." Advances in Engineering Technology Research 12, no. 1 (2024): 1280. https://doi.org/10.56028/aetr.12.1.1280.2024.
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With the development of sugar-substituted food, bakery products have been more and more concerned about the health of consumers. Erythritol, as a natural sweetener, is difficult to directly replace sugar in bakery products due to its unique physicochemical properties and needs to be compounded with different raw materials to achieve the best sugar-substituting effect. This paper explores the product development of erythritol in sucrose-free bread, sucrose-free croissants and sucrose-free cakes. Different compounding ratios were determined. In whole wheat bread sugar substitution; the content of energy, carbohydrate and sodium in the sugar substitution group was significantly lower than that in the sucrose group, with a decrease of 7.0%, 13.2% and 4%, respectively, and the content of dietary fibre was significantly higher than that in the sucrose group, and increased by 38.8%. For sucrose-free croissants: the energy and carbohydrate contents of the sugar substitute group were significantly lower than those of the full-sugar group, with decreases of 3.8% and 6.4%, respectively, and the content of dietary fibre was higher than that of the full-sugar group. For sucrose-free cake: the energy and carbohydrate contents of the sugar substitute group were significantly lower than those of the sucrose group by 9.6% and 25%, respectivelyr.
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Yang, Kun, Zheng Wang, Tom Brenner, Hiroe Kikuzaki, Yapeng Fang, and Katsuyoshi Nishinari. "Sucrose release from agar gels: Correlation with sucrose content and rheology." Food Hydrocolloids 43 (January 2015): 132–36. http://dx.doi.org/10.1016/j.foodhyd.2014.05.007.
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Verma, Indu, Kriti Roopendra, Amaresh Chandra, and Aisha Kamal. "Biochemical Profiling of Source and Sink Tissues at Different Growth Stages of Early and Late Maturing Varieties of Sugarcane (Saccharum spp. hybrids)." Biosciences, Biotechnology Research Asia 15, no. 3 (2018): 611–18. http://dx.doi.org/10.13005/bbra/2667.
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Sugarcane being C4 crop exhibits distinct source-sink signaling pathway that helps in storing remarkably high amount of sucrose in its sink tissues that makes it a highly remunerable crop worldwide. In the present study sugar content was profiled in both source and sink tissues of early (CoJ64) and late (BO91) maturing sugarcane varieties. At early growth stage (i.e. at 210 DAP) sink tissues of both varieties exhibited higher reducing sugar and low sucrose content while in source tissues both sucrose and reducing sugar content was observed high, depicted lower sink demand for sucrose. With maturity, when sink demand for sucrose storage increased, rise in sucrose content was seen in sink tissues, whereas in source tissues gradual decrease in sucrose and reducing sugar content was observed. Accumulation of sucrose was found much higher in CoJ64 than those in BO91. In CoJ64 maximum sucrose content (64.2%) was seen at 330 DAP while in BO91 it was 41.8% at 390 DAP. At this stage, source tissues too exhibited higher sucrose and reducing sugar content. Thus sucrose synthesis in source tissues and its transportation to the sink tissues is primarily governed by the sink demand.
Dissertations / Theses on the topic "Sucrose content"
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Glover, Natasha Marie. "The Genetic Basis of Phytate, Oligosaccharide Content, and Emergence in Soybean." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/77157.
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Soybean [Glycine max (L.) Merr] is one of the U.S.'s most economically important crops due to the protein and oil content of seeds. The major storage form of phosphorus in soybean seeds is found in the form of phytate, but because of its negative nutritional and environmental impacts, seed phytate and raffinosaccharide content have been a recent focus of breeders and molecular geneticists. The soybean line CX1834 is a low phytate mutant known to have two low phytate QTLs on linkage groups (LGs) L and N. The first objective of this research was to determine the genetic basis of the low phytate trait in CX1834. By using the whole genome sequence, we identified two candidate multidrug resistance-associated (MRP) ABC transporter genes. Sequencing the genes from CX1834 and comparing them to the reference genome sequence revealed a single nucleotide polymorphism (SNP) in the MRP gene located on LG N (causing a stop codon), and a SNP mutation in the MRP gene located on LG L (causing an amino acid change from arginine to lysine). One major concern with low phytate soybeans is the low seedling emergence. The second objective was to undertake a population-wide study of emergence in the recombinant inbred population CX1834 x V99-3337, over two years and two locations. We found a positive correlation between phytate level and emergence, and that variation among year, location, genotypic class, year x genotypic class, and year x location interactions were significantly affecting emergence.
V99-5089, in addition to being low phytate, has high sucrose and low raffinosaccharide content. This phenotype of V99-5089 has been previously determined to be due to a SNP mutation in its myo-inositol phosphate synthase (MIPS) gene located on LG B1. The third objective was to use the recombinant inbred population derived from CX1834 x V99-5089 to observe the combinations of all three mutations to see how the different alleles impact phytate and raffinosaccharide content. The individuals with all three mutations, as well as those with the two MRP mutations together had lower phytate than the other genotypic classes. However, these lines (all three mutations) had unexpectedly high stachyose.<br>Ph. D.
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Biasio, Irene. "Study of polyphenols content and antioxidant activity of apple samples osmo-dehydrated with sucrose and fruit based solutions." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
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La disidratazione osmotica è una tecnica che permette la riduzione del contenuto d’acqua di un alimento mediante l’immersione dello stesso in una soluzione ad alta pressione osmotica. La differenza in pressione osmotica genera due flussi opposti tra l’alimento e la soluzione osmotica portando a perdita di acqua e contemporaneo arricchimento dell’alimento immerso. Inoltre, utilizzando soluzioni osmotiche con succhi concentrati a base di frutta è possibile migliorare le caratteristiche organolettiche e la composizione del prodotto finale. Infatti, oggigiorno i trend mostrano sempre di più un interesse dei consumatori nei confronti di alimenti funzionali o arricchiti. Tra i composti più noti per la loro attività antiossidante, i polifenoli sono un gruppo eterogeneo di composti che si possono trovare naturalmente in svariati frutti e che mostrano un’elevata capacità antiossidante nei confronti di specie reattive (ROS, RNS). Frutti come il mirtillo (Vaccinium myrtillus) e l’aronia (Aronia melanocarpa) sono particolarmente ricchi in polifenoli, in particolare in antocianine. L’applicazione di un trattamento di disidratazione osmotica precedente all'essiccamento ha dimostrato essere un’ottima tecnica per ottenere un prodotto finale disidratato ed arricchito. Mediante la disidratazione osmotica è possibile ottenere un a importante riduzione del contenuto iniziale d'acqua dell’alimento, riducendo anche i successivi tempi e costi di essiccamento. Lo zucchero presente nelle soluzioni osmotiche protegge l’alimento da modificazioni ,come l’imbrunimento, mantenendo il colore brillante. Inoltre, l’utilizzo di soluzioni osmotiche a base di aronia e mirtillo ha mostrato un aumento della quantità totale di polifenoli e, di conseguenza anche dell’attività antiossidante, che si sono mantenuti tali anche dopo l’essiccamento.
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Cicek, Mine II. "Genetic Analysis of Quantitative Trait Loci Associated with Seed Sucrose Content Using Molecular Markers in an Interspecific Glycine Cross." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36506.
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Sucrose content is one of the important seed quality traits in soybean, especially for oriental soyfood production. However, little genetic information is available on this quantitative trait yet.
A previous study was conducted on seed sucrose content of soybean using a population of F2-derived lines from an interspecific cross between an adapted high-sucrose (8.3%) G. max breeding line (V71-370) and a low sucrose (1.6%) G. soja plant introduction (PI407162). Nineteen marker loci, mapping to seven linkage groups (A1, A2, E, F, L1, I, and M), were significantly associated with seed sucrose content after screening 178 polymorphic genetic markers, including RFLPs, SSRs, RAPDs and morphological markers. The replicated field experiments were planted in 1993 and 1995.
The objective of my study was to evaluate QTLs associated with seed sucrose content utilizing an additional 153 F2:3 families from the same cross.
DNA samples from the additional families were analyzed with the nineteen genetic markers associated with sucrose in the previous study. Sucrose data were obtained from seeds harvested from a field experiment conducted in 1995. Single factor analysis of variance results for the sucrose data obtained from the 153 F2:3 families were compared to the 1995 data for the 144 F2:3 families of the previous study.
Of the nineteen genetic markers significantly associated with seed sucrose content in the previous study, seven were also significantly associated in this study. These genetic markers include sgA458a on linkage group A2, NBS61 on linkage group E, sgB164, R-B4a and sgB162 on linkage group L1, and R-B4b and sgA144 on linkage group I. The percent phenotypic variation explained by significant individual markers varied from 2.9 to 6.8% in the 153 F2:3 families.
This study shows that seed sucrose content, a quantitative trait, may be improved using the molecular marker technology. Further research is necessary in different genetic backgrounds of G. max in order to implement these markers in a breeding program for selection.<br>Master of Science
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Duchaine, Caroline. "La consommation d'aliments contenant du sucre ajouté et la densité mammaire." Master's thesis, Université Laval, 2014. http://hdl.handle.net/20.500.11794/25201.
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Une consommation élevée de sucre a été associée à une augmentation du risque de cancer du sein dans plusieurs études. Nous avons examiné l’association entre la consommation d’aliments contenant du sucre ajouté et la densité mammaire (DM), un facteur de risque important du cancer du sein, chez 1555 femmes québécoises. La consommation de boissons contenant du sucre ajouté était corrélée positivement avec le pourcentage de DM (r=0,054, P=0,038) et la DM absolue (r=0,051, P=0,049) dans la population totale. Cette dernière corrélation demeurait significative chez les femmes pré-ménopausées seulement lors des analyses stratifiées (r=0,088, P=0,016). Ces analyses ont aussi révélé une corrélation positive entre la consommation d’aliments solides contenant du sucre ajouté et la DM chez les femmes post-ménopausées (r=0,073, P=0,048). En conclusion, la consommation de certains aliments contenant du sucre ajouté et en particulier de boissons, semble être associée à une DM plus élevée.<br>A high intake of sugar has been associated with an increased risk of breast cancer in several studies. We examined the association between sweet foods and drinks intake and mammographic density (MD), a strong breast cancer risk factor, among 1555 women in Quebec city. Consumption of sugar-sweetened beverages was positively correlated with percent MD (r=0.054, P=0.038) and absolute MD (r=0.051, P=0.049) in the total population. The latter correlation remained significant among premenopausal women only in stratified analyzes (r=0.088, P=0.016). These analyzes also revealed a positive correlation between sweet foods intake and MD among postmenopausal women (r=0.073, P=0.048). In conclusion, the consumption of sweet foods and especially sugar-sweetened beverages seems to be positively associated with MD.
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Becker-Silva, Sandra Cristina. "Limites de tolerância do espermatozóide caprino a soluções hiperosmóticas de sacarose e taxa de sobrevivência após criopreservação em diluentes contendo sacarose ou trealose e concentrações reduzidas de crioprotetores permeantes." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/10/10131/tde-16062005-113024/.
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Foi conduzida uma série de experimentos onde se buscou definir: 1) o limite de tolerância do espermatozóide caprino a soluções hiperosmóticas de sacarose; 2) um diluente para criopreservação de sêmen que minimizasse as flutuações de volume celular. O limite de tolerância da membrana, avaliado pelo corante eosina-nigrosina, foi de 930 mOsm em soluções de sacarose em Ringer-lactato a 38oC. Os danos à integridade de membrana (IM), em osmolalidades acima deste valor, se estabeleceram no primeiro minuto de exposição e não se agravaram até 10 minutos depois. A motilidade (MOT) foi mais afetada que a IM. A rediluição abrupta em meio isosmótico causou dano extenso e proporcional ao grau de desidratação prévia. Nos experimentos seguintes, adição de 375 mM de sacarose ao diluidor TRIS-gema com 6,8% de glicerol (TGG), 5 minutos antes da congelação, resultou em MOT e IM similares ao controle TGG sem sacarose. Descongelação e rediluição a 4oC favoreceram a MOT e, a 38oC, favoreceram a IM. O diluente TRIS-gema com 375 mM de sacarose e concentração de glicerol reduzida para 1,7% apresentou melhor MOT e IM que o controle (65% e 187% vs 52% e 100%, respectivamente). A MOT após 2 h e o vigor após 6 h foram maiores quando a rediluição pós-descongelação foi em 5 passos se comparado a 3 passos (28% e 9% vs 19% e 2%, respectivamente). Na fase seguinte do trabalho, diluentes elaborados com 300 mM após 6 h a 38oC, melhor MOT e vigor que o controle (33% e 26% vs 15% e 10%, respectivamente). A descongelação a 20oC favoreceu a MOT e o vigor nos tempos zero, 2 h e 6 h pós-descongelação em todos os grupos contendo sacarose. O etilenoglicol não diferiu do glicerol na concentração de 3,4% quando adicionado a diluente contendo 300 mM de sacarose. Nestes diluentes, a rediluição em 5 passos a 20oC não diferiu em MOT e IM da feita em 1 passo a 38oC. No último experimento, sêmen congelado em diluente contendo 300 mM de trealose e zero% de glicerol mostrou melhor IM após descongelação em um passo a 38oC (320% vs 100% no controle) e maior MOT às 6 h após descongelação e rediluição em 5 passos a 20oC (56% vs 26% no controle). Conclui-se que o sêmen caprino tolera soluções de sacarose até o limite de 930 mOsm, mas a rediluição deve ser progressiva. A desidratação parcial, causada por soluções concentradas de sacarose ou trealose, permite a congelação de sêmen sem adição de crioprotetores permeantes. Os melhores resultados foram obtidos em diluente TRIS-gema sem glicerol e adicionado de 300 mM de trealose.<br>The objective of this study was to: 1) define the tolerance limits of goat sperm to hyperosmotic sucrose solutions; 2) establish an extender that minimizes cell volume variations during the processes of freezing and thawing. Boer goat semen was diluted with Ringer-lactate-Sucrose solutions at 38oC. The hyperosmotic tolerance limit was 930 mOsm evaluated with eosin-nigrosin stain. At osmolalities above this value, damage was evident after 1 min and was not affected by further exposure. Redilution in a single step resulted in massive membrane damage that was nearly proportional to the dehydration intensity previously undergone. Motility (MOT) was more distinctly impaired than membrane integrity (MI). In the next experiments, addition of 375 mM sucrose (Suc) 5 min previous to freezing to TRIS-egg yolk extender containing 6.8% glycerin (TYG) resulted in sperm motility (MOT) and MI similar to control extender TYG without sucrose. Thawing and redilution at 4oC affected favorably the MOT, and at 38oC, was favorable to MI. When freezing in TRIS-egg yolk-Suc extenders with low glycerin concentration (1.7%) MOT and MI were significantly higher than in the control TYG (65% and 187% vs 52% and 100%, respectively). MOT 2 h after thawing and intensity of motility (INTMOT) after 6 h after thawing were better preserved after a redilution of 5 increasing volume-steps than after redilution of 3 steps (28% and 9% vs 19% and 2%, respectively). In sequence, extenders containing 300 mM sucrose and thawed-rediluted 5 steps at 20oC improved MOT and INTMOT after 6 h (33% and 26% vs 15% and 10% in the control Group). The thawing-redilution at 20oC improved the results in all groups containing sucrose. At a concentration of 3.4% added to TRIS-yolk extender with 300 mM sucrose, the cryoprotectant ethylene glycol gave similar results as glycerin. MOT and INTMOT in the different time intervals were not influenced by redilution in 5 steps at 20oC or in one step at 38<SUPoC. In the last experiment made, semen frozen in a TRIS-yolk extender with 300 mM trehalose and devoid of glycerin showed the best MI after thawing-redilution in 1 step at 38oC (320% vs 100% in the control Group). The highest MOT after 6 h incubation was observed when this group was thawed-rediluted at 20oC in 5 steps (56% vs 26% in the control). From the results obtained it may be concluded that the upper tolerance limit of goat spermatozoa to hyperosmotic sucrose solutions is 930 mOsm. The redilution and return to isosmolality should be stepwise made. Goat semen can be frozen in extenders devoid of permeant cryoprotectants like glycerin when, previous to freezing, the cells are partially dehydrated by concentrated sucrose or trehalose solutions. The best survival rate was obtained when freezing goat spermatozoa in a glycerin-free TRIS-yolk-extender containing 300 mM of trehalose.
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Melo, Lauro Luis Martins Medeiros de. "Perfil sensorial como ferramenta para o desenvolvimento de chocolates ao leite Diet em sacarose e Light em calorias contendo substitutos da sacarose e de gordura." [s.n.], 2008. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254224.
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Orientador: Helena Maria Andre Bolini<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos<br>Made available in DSpace on 2018-08-12T13:31:07Z (GMT). No. of bitstreams: 1
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Previous issue date: 2008<br>Resumo: Atualmente, há um interesse crescente de consumidores do mundo todo por alimentos e bebidas com menores quantidades de calorias. Neste contexto, a Análise Sensorial é a única forma de se determinar a aceitação e o perfil em relação à aparência, aroma, sabor e textura de alimentos e bebidas, sendo, portanto, uma ferramenta insubstituível. Com base nestes fundamentos, o objetivo do presente projeto foi realizar a determinação de doçura ideal, doçura equivalente de diferentes edulcorantes, análise descritiva quantitativa (ADQ) e análise de aceitação (com mapas de prerência interno, extendido e análise de regressão de mínimos quadrados parciais, Partial Least Squares - PLS) de chocolates adoçados com diferentes edulcorantes (estévia e sucralose) e sacarose (convencional), e com substituto de gordura (concentrado de soro de leite, WPC), comparando seus comportamentos sensoriais, para a obtenção de uma formulação de alta qualidade sensorial. Também foi incluída ao estudo uma amotra diet (em sacarose) comercial. A ADQ e a análise de aceitação foram conduzidas ao longo da estocagem dos chocolates a 20 °C em 0, 3, 6 e 9 meses. A análise de aceitação foi conduzida tanto com consumidores não-diabéticos quanto com diabéticos. Também foram realizadas análises no NCSU Sensory Service Center da North Carolina State University nos Estados Unidos, incluindo análise descritiva, aceitação e conjoint analysis. Foi possível produzir chocolates ao leite diet (em sacarose) e diet (em sacarose)/light (em calorias) com sucralose e estévia como substitutos da sacarose e WPC como substituto parcial de gordura com curvas tempointensidade do gosto doce similares à curva tempo-intensidade do chocolate ao leite convencional de melhor aceitação dentre os testados (43% de sacarose). Houve poucas alterações nos chocolates desenvolvidos em relação ao chocolate convencional. A amostra de chocolate ao leite convencional adoçada com sacarose caracteriza-se mais pelos atributos aroma doce e doçura. As amostras adoçadas com sucralose e sucralose/WPC são caracterizadas, principalmente, pelo atributo sabor de leite em pó (aumentado pelos agentes de corpo lactitol/polidextrose e pelo substituto de gordura WPC). As amostras com estévia se caracterizam pelos atributos amargor e residual amargo. A amostra comercial foi caracterizada por aroma de manteiga de cacau e derretimento na boca. A maioria dos atributos sensoriais das amostras não foi significativamente alterada até o término do estudo aos 9 meses. A comparação das equipes de provadores do Brasil e dos Estados Unidos mostrou que equipes de provadores altamente treinadas usando terminologia padronizada e representativa podem fornecer resultados similares. As amostras convencional e comercial apresentaram as maiores aceitações entre consumidores não-diabéticos. As alterações observadas nos perfis sensoriais não foram suficientes para provocar mudança na aceitação das amostras durante o período de estocagem, o que garante uma vida-de-prateleira efetiva de pelo menos 9 meses. Análise de cluster dividiu os consumidores em dois grupos. As médias de aceitação das amostras convencional e comercial para o grupo 2 foram significativamente maiores. Para o grupo 1, não houve diferença entre as médias de aceitação das amostras convencional, sucralose e sucralose/WPC. As amostras produzidas com sucralose são tão bem aceitas quanto à amostra comercial entre consumidores diabéticos. Todos os chocolates desenvolvidos (diet em sacarose e diet em sacarose/light em calorias, com sucralose ou estévia) apresentaram médias de aceitação estatisticamente maiores entre diabéticos do que entre não-diabéticos. Os consumidores se dividiram principalmente para a amostra convencional e para a amostra comercial. A doçura foi o atributo mais importante para o primeiro grupo enquanto os atributos derretimento na boca e aroma de manteiga de cacau foram mais importantes para o segundo grupo. Estas tendências se mantiveram até o fim do estudo de tempo de estocagem aos 9 meses. Para consumidores dos Estados Unidos, o atributo declaração sobre açúcar é mais importante para diabéticos do que para não-diabéticos enquanto que o tipo de edulcorante e a redução calórica têm a mesma importância para ambos os grupos. Teoricamente, um chocolate com declaração ¿livre de açúcar¿, edulcorante natural e 25% de redução calórica seria a melhor combinação. Os consumidores dos Estados Unidos foram divididos em três grupos, sendo que o grupo 1 se assemelha mais aos diabéticos em geral, e os grupos 2 e 3, aos nãodiabéticos. A principal diferença entre os grupos 2 e 3 está no fato de o grupo 2 ser mais atento ao consumo de calorias. Nos Estados Unidos, convencional, sucralose e sucralose/WPC foram as amostras com melhor aceitação entre não-diabéticos e sucralose, sucralose/WPC e comercial, entre diabéticos, não confirmando o resultado teórico da conjoint analysis. Os consumidores diabéticos são mais receptivos a chocolates ao leite diet (em sacarose) e diet (em sacarose)/light (em calorias) do que consumidores não-diabéticos<br>Abstract: Nowadays, there is an increasing interest in foods and beverages with smaller amounts of calories. Then, Sensory Evaluation is the most important tool for evaluation of acceptance and sensory characteristics regarding appearance, aroma, flavor and texture of foods. Therefore, objective of the current study was determination of the most accepted sweetness, equi sweet concentration for different sweeteners, quantitative descriptive analysis (QDA) and acceptance testing (using internal and extended preference mappings and PLS regression) of chocolates sweetened with differente sweeteners (steviosídeo and sucralose) and sucrose (conventional), and with whey protein concentrate (WPC) as fat replacer, comparing their sensory characteristics, in order to get a high sensory quality recipe. This research also included a commercial sugra-free sample. QDA and acceptance testing were performed during storage time at 20 °C after 0, 3, 6 and 9 months. Acceptance testing was performed with both non-diabetic and diabetic consumers. In addition, some analyses were carried out at NCSU Sensory Service Center at North Carolina State University, in the USA, including descriptive analysis, acceptance testing, and conjoint analysis. Lab developed prototypes sugar-free and reduced calorie milk chocolates with sucralose or stevioside and WPC as fat replacer presented time-intensity curves similar to most accepted chocolate with sucrose (43%). There were few changes comparing lab developed prototypes to convencional chocolate. Sweet aroma and sweetness were the most important attributes for conventional milk chocolate sweetened with sucrose while milky flavor (increased by bulking agents lactitol/polydextrose and by fat replacer WPC) was the most important attribute for samples sweetened with sucralose and sucralose/WPC. Bitterness and bitter aftertaste were the most important attributes for samples sweetened with stevioside. Regarding commercial sample, cocoa butter aroma and melting rate were the most important attributes. There were not significant changes in most of sensory attributes during 9-month storage time. Comparisons with Brazilian and USA panels showed that highly trained panels using standardized, representative languages can provide comparable results. Conventional and commercial chocolates presented higher acceptance means for non-diabetic consumers. Effects of aging on some sensory characteristics of chocolates were not enough to change consumer acceptance over time, which assures a realistic shelf life for at least 9 months. Cluster analysis presented two groups. Conventional and commercial chocolates presented higher acceptance means for group 2. For group 1, there was no difference between acceptance means for conventional, sucralose, and sucralose/WPC. Diabetic consumers accept samples produced with sucralose so well as they accept commercial sample. All lab developed prototypes presented higher acceptance means among diabetics compared to non-diabetics. Consumers presented preferences especially for conventional sample or for commercial sample. Sweetness was the most important attribute for the first group while melting rate and cocoa butter aroma were the most important attributes for the second group. These results lasted until the end of storage time (9 months). For USA consumers, sugar claim attribute is more important for diabetics than for non-diabetics while sweetener type and calorie reduction attributes have the same importance for both groups. A chocolate with sugar-free claim, natural sweetener and 25% calorie reduction would be theoretically the best combination. USA consumers were segmented in 3 clusters and cluster 1 was more similar to diabetics while clusters 2 and 3 were more similar to non-diabetics. The main difference between clusters 2 and 3 is consumers in cluster 2 are more concerned about calorie consumption. In the USA, conventional, sucralose, and sucralose/WPC were the most accepted samples among nondiabetics and sucralose, sucralose/WPC, and commercial were the most accepted samples among diabetics, which did not confirm theorical results of conjoint analysis. Diabetic consumers are more accepting than non-diabetic consumers of diabetic and diabetic/reduced calorie milk chocolates<br>Doutorado<br>Consumo e Qualidade de Alimentos<br>Doutor em Alimentos e Nutrição
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Bouhlal, Sofia. "Consequence of salt, sugar and fat content modifications in foods on children's preference and intake." Thesis, Dijon, 2011. http://www.theses.fr/2011DIJOS110/document.
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Contexte : En France, le Programme National Nutrition Santé (PNNS) est en charge d’appliquer les recommandations visant à diminutions les quantités de sel, de sucre et de matières grasses dans les aliments. Cependant, l’effet de ces réductions sur les préférences et les consommations est mal connu. Objectifs : Ce travail vise à comprendre l'impact des variations de sel, de sucre et de matières graisses dans les aliments, sur les préférences et les consommations alimentaires des enfants.Méthodes : Des études ont été menées dans l’environnement habituel du repas des enfants (crèche ou cantine scolaire), aux heures normalement prévue pour le déjeuner et / ou le goûter.Résultats : Concernant le saccharose, l'ajout d'une faible quantité paraît suffisant pour induire un prise alimentaire; ainsi, le saccharose peut être réduit sans affecter les préférences ni les consommations alimentaires. Dans la mesure où le gras est concerné, la suppression ou l’ajout de beurre n'a pas eu un impact immédiat sur la consommation des haricots verts ou celle des pâtes. Quant aux produits allégés en matière grasse, ils semblent être bien acceptés par les enfants et les adultes. Concernant le sel, sa réduction semble plus délicate et devrait donc être considérée avec prudence. Par ailleurs, nos résultats mettent en évidence la dissociation entre l'effet positif et directe du sel sur les préférences et les consommations d’un côté, et son rôle sur l'apprentissage de l’autre.Conclusions : Les qualités sensorielles des aliments sont importantes pour le comportement alimentaire. Cependant, alors qu’il semblerait que des réductions de sucre et de gras sont possibles, contribuant ainsi à réduire l'apport énergétique, celles concernant le sel doivent être considérées avec prudence<br>Background: In France, the National Nutrition and Health Programme (“Programme National Nutrition Santé” or “PNNS”) is in charge of implementing the recommendations aiming at reducing salt, sugar and fat quantities in foods. However, the extent to which this might impact children’s food preferences and intake is limited. Objective: The present work aimed at understanding the impact of varying salt, sugar and fat variations in foods, on toddlers and children’s food preferences and intake. Methods: Studies were conducted in toddlers’ and children’s natural eating environment (nursery and school canteen), at their usually scheduled lunch and/or snack times. Results: Concerning sucrose, the addition of a low amount seems enough to trigger intake; thus, sucrose can be reduced without affecting food preferences and intake. As far as fat is concerned, suppressing or adding butter did not have an immediate impact on toddlers’ green beans or pasta intake. Besides, low-fat products seem to be well accepted by toddlers and adults. Concerning salt, its reduction seems more puzzling and should be considered cautiously. Our results highlighted dissociation between the direct positive effect of salt on food preferences and intake, and its role on learning. Conclusions: Food sensory qualities are important for eating behaviour. Although it seems that reductions of sugar and fat in foods are possible, thus helping to reduce energy intake, those concerning salt should be considered cautiously
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Abadie, Cyril. "Exploration de la variabilité phénotypique d'Arabidopsis thaliana (L.) Heynh et caractérisation de l'effet d'un déficit hydrique sur la photosynthèse et le contenu glucidique foliaire des écotypes Col-0, Mt-0 et Shahdara." Thesis, Poitiers, 2012. http://www.theses.fr/2012POIT2280/document.
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Compte tenu des changements climatiques annoncés, les végétaux risquent d'être confrontés, dans un proche avenir, à des épisodes de sécheresse sévères de plus en plus fréquents. Afin de prédire l'impact de telles contraintes sur la productivité et le rendement des plantes cultivées, il convient d'étudier l'effet du manque d'eau sur l'activité photosynthétique, le transport et l'accumulation des sucres. Dans un premier temps, la croissance, le développement, la biomasse et la photosynthèse de huit écotypes d'Arabidopsis thaliana ont été caractérisés. Trois de ces écotypes (Col-0, Mt-0 et Shahdara) ont ensuite été soumis à une période de déficit hydrique. Une chute du contenu relatif en eau des rosettes (RWC), de la conductance stomatique (gs) et de l'assimilation nette (AN) a été observée précocement chez Mt-0, écotype initialement caractérisé par une très faible efficience de l'utilisation de l'eau (AN/E). En réponse au stress, l'analyse des courbes AN/Ci de chaque écotype montrait que la limitation stomatique s'accompagne rapidement de limitations métaboliques (baisse de la Vcmax). En fin de stress hydrique, une diminution des réserves en amidon a conduit dans tous les cas à une accumulation de saccharose dans les feuilles. Les expressions des gènes codant les principaux transporteurs foliaires de sucres (polyols, hexoses et saccharose) étaient quant à eux différemment affectés par le manque d'eau. Shahdara, qui est parvenu à conserver un RWC relativement élevé, est l'écotype qui a le mieux toléré la contrainte hydrique. À l'opposé, Mt-0 présentait, en fin de stress, une inhibition de l'AN couplée à des altérations majeures et irréversibles des photosystèmes II (chutes de qP et de Fv/Fm)<br>Considering the predicted climate changes, plants are likely to face, in the future, severe and frequent droughts. In order to evaluate the impact of such stress on productivity and crop yield, the effect of water shortage on photosynthetic activity, sugar transport and accumulation was investigated. Firstly, growth, development, biomass and photosynthesis of eight Arabidopsis thaliana ecotypes have been characterised. Secondly, three of them (Col-0, Mt-0 and Shahdara) were subjected to drought stress. The relative water content (RWC), the stomatal conductance (gs) and the net assimilation (AN) decreased early in rosette leaves of Mt-0 which was initially characterized by a very low water use efficiency (AN/E). In response to drought, AN/Ci curves analysis for each ecotype showed that stomatal limitation was quickly related with metabolic limitations (lower Vcmax). At the end of the stress, reduced starch content always led to a sucrose accumulation in leaves. The expression of genes encoding the main leaf sugar carriers (polyols, hexoses and sucrose) was differently impaired by the water shortage. Shahdara, that managed to maintain a relatively high RWC, was the most tolerant ecotype to water stress. In contrast, at the end of the stress, Mt-0 exhibited an AN inhibition together with significant and irreversible photosystem II alterations (drop of both qP and Fv/Fm)
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Masavang, Supuksorn. "Sugar reduction in extruded cereal based products : impact of water content on the structure and molecular dynamics in such material." Thesis, Bourgogne Franche-Comté, 2019. http://www.theses.fr/2019UBFCK025/document.
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Les systèmes à base de biopolymères à faible teneur en humidité sont couramment rencontrés dans les aliments. Bien entendu, il est primordial de comprendre les bases physiques de leur qualité: texture, performances dans le temps ou en fonction de leur composition. Le vieillissement physique des systèmes composites rend les changements survenant dans le stockage des produits comestibles difficiles à prévoir. Les objectifs de ce travail étaient d'évaluer l'incidence de la présence de saccharose et de la teneur en eau de fabrication sur les propriétés physico-chimiques du produit fini. La stabilité physique de ces matériaux a été contrôlée grâce à une étude à différentes échelles moléculaires. Ensuite, les relations entre les données multi-échelles ont été examinées. L'effet du saccharose (0 à 20%) et de l'eau d'alimentation (10 et 15%) sur les mélanges d'extrusion a été étudié à l'aide d'un extrudeur double vis conduit dans les mêmes conditions. Les propriétés physiques et microstructurales des produits extrudés expansés ont été examinées sous diverses conditions d'humidité relative. La réduction des teneurs en sucre et en eau d’alimentation a fait augmenter la pression et l’énergie mécanique spécifique, ce qui a réduit la dégradation de l’amidon et augmenté la viscosité dans l’extrudeur en particulier à la teneur en eau la plus élevée. L'augmentation de la pression dans l’extrudeur a entraîné une expansion plus importante des extrudés. Par contre, la technique d'imagerie neutronique montré que le saccharose réduisait la taille des pores, et donc augmentait la densité apparente et ce qui était particulièrement évident en utilisant. Cette technique a été appliquée pour la première fois sur des produits extrudés. Les images de tomographie 2D ont indiqué des différences structurelles internes entre les extrudés à différentes teneurs en saccharose et stockés à humidité relative différente. Toutefois, l'analyse d'images 3D a montré que l'impact de ces facteurs sur la distribution de la taille des pores et le taux de porosité n'était pas significatif. En fin d'extrusion, les échantillons étaient à l'état amorphe à la suite de la gélatinisation de l'amidon et de la fonte du sucre. Leursrs propriétés thermiques ont été analysées par analyse enthalpique différentielle (AED) et les températures e transition vitreuse ont été étudiées. Les thermogrammess d’AED ont été minutieusement étudiés via une déconvolution de la dérivée première de la variation d’enthalpie. Cette approche a mis en évidence que les systèmes composites étudiés présentaient des phases multiples avec des transitions vitreuses distinctes. Ces dernières sont associées à une phase riche en polymère (amidon principalement) et / ou à une phase riche en plastifiant (sucre) dont le comportement dépendait de la teneur en eau de l'échantillon. Les isothermes de sorption ont montré qu’aux faibles Aw et pour une valeur donnée, a la teneur en eau des extrudés diminuait avec l’augmentation des teneurs en saccharose et que l'effet inverse était observé aux aw élevées. L’étude de la cinétique apparente de lala diffusion de l'eau a mis en évidence deux sites de sorption différents. Le premier est caractérisé par une cinétique quasi constante qui pourrait correspondre à un phénomène d'adsorption à la surface. Le second site présente d’abord un ralentissement initial de la cinétique de sorption, tandis qu’une forte augmentation est constatée lorsque la teneur en eau était plus élevée. Ce comportement peut être lié à un effondrement de la structure. Une étude par RMN à cyclage de champ rapide à basse fréquence a montré que les temps de relaxation dépendaient de la teneur en saccharose et en eau. Une carte de stabilité a été tracée pour modéliser les évolutions rhéologiques des matrices avec la teneur en eau en lien avec les transitions de phases des matériaux (...)<br>Low-moisture biopolymer-based systems are commonly encountered in food. Obviously, understanding the physical basis of their quality: e.g texture, or performance over time or as a function of their composition is of primary importance. The objectives of this work were to evaluate how the presence of sucrose and water content affects physico-chemical properties. The physical stability of these materials were monitored through an insight at different molecular scales. Then the relations between the multi-scale studies were investigated. The effect of sucrose (0–20%) and feed water (10 and 15%) on extrusion blends was studied using a twin screw extruder under the same processing settings. The physical and microstructural properties of extruded products were examined at various RH. Reducing both sugar levels and feed water increased die pressure and specific mechanical energy, as a consequence, it reduced starch degradation and increased in viscosity. The effect was more pronounced with increasing feed water content. The increased die pressure resulted in higher expansion of the porous extrudates. Sucrose was shown to increase the bulk density and reduce the pore size, this was particularly evident by using neutron imaging technique. This technique was applied for the first time in extrudate. 2D tomography images indicated internal structural differences between extrudates containing different sucrose content and stored at low and high % RH, while 3D image analysis showed impact of these factors on pore size distribution and % porosity were not significant. The extruded samples were in the amorphous state as a result of starch gelatinization and sugar melting. Their thermal properties were analyzed with DSC and their Tg were studied. The DSC thermograms were thoroughly studied through a Gaussian deconvolution of the first derivative of their heat low. This approach evidenced a multiple phase behavior with different glass transitions in composite systems. They were associated with either a polymer-rich phase and/or a plasticizer-rich phase which behavior depended on the sample water content. Physical aging accompanied with an increase in rigidity at low aw, resulted in an increased bulk density and more pronounced with increasing sucrose content. Sorption isotherms showed the water content of extrudates decreased when product contains high sucrose at low aw range and the inverse effect was observed at high aw. Apparent kinetics of water diffusion showed two different sorption sites, the first kinetics was almost constant and could be adsorption phenomena at the surface. The second one reflected first an initial slowing in dynamics whereas a sharp increase was found at higher water content. Addition of sucrose or water decreased both Tgs in extrudates. Young's modulus showed water acts as anti-plasticizer at low aw, while it shows a plasticizing effect at high aw. A stability map can explain the brittle-ductile transition occurred below Tg. Fast field cycling NMR study at low frequency highlighted that T1 depended on sucrose and water content. T1 and T2 measured using Low field NMR decrease as a function of water content, while the impact pf sucrose were not significant. T2 showing a minimum probably indicating the exchange of protons of water and macromolecules in composite system. The impact of sucrose content was not significant for T1 and for T2 at low water content. FFC NMR showed T1 results consistent with the LF NMR measurement.In conclusion, physicochemical studies of the influence of water and sucrose content on glassy materials showed that the material properties can be investigated at different levels from the macro- to the microscopic scale and these results clearly presented the need for complementary techniques to probe the dynamics in the glassy state of heterogeneous food systems that could be facilitated to manage the stability during storage of this type of dry products
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Ledru, Hélène. "Synthèse chimique d’oligosaccharides de la zone de liaison des protéoglycanes et nouvelles méthodes d’activation pour l’obtention de sucres sulfatés." Thesis, Orléans, 2017. http://www.theses.fr/2017ORLE2036/document.
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Les protéoglycanes sont des macromolécules composées de glycosaminoglycanes (GAGs), liés de manière covalente à une protéine porteuse. Les GAGs sont impliqués dans de nombreux processus biologiques, comme la croissance et la prolifération des cellules, et également dans de nombreuses pathologies, incluant l’arthrose, la maladie d’Alzheimer et des cancers. Leur biosynthèse fait intervenir des O-glycosyltransférases et commence par la formation de la zone de liaison tétrasaccharidique. Celle-ci initie la formation de deux types de chaînes de GAGs, les héparines / sulfates d’héparine avec l’action de l’EXTL3 et les sulfates de chondroïtines ou de dermatanes avec l’action de la CSGalNAcT-1. Dans cette biosynthèse, la zone de liaison peut être sulfatée mais le rôle de ces sulfatations est encore peu connu.L’objectif de ce travail était de synthétiser des disaccharides de la zone de liaison ainsi que les trisaccharides de transfert, avec le premier sucre aminé des chaînes de GAGs, diversement monosulfatés ou non, dans le but de comprendre le rôle de ces sulfatations sur les enzymes de bifurcation.Différentes méthodes d’activation, micro-ondes et chimie en flux continu, ont également été testées pour sulfater des mono-, di- et trisaccharides<br>Proteoglycans are macromolecules composed of glycosaminoglycans chains (GAGs) covalently linked to a core protein. GAGs are implicated in many biological processes, such as cells growth and proliferation, and they are also involved in several diseases including osteoarthritis, Alzheimer’s disease and cancers. Their biosynthesis involves the action of O-glycosyltransferases and starts with the formation of a tetrasaccharidic linkage region. This GAGs linkage region initiates the formation of two types of GAGs chains, heparin/heparan sulfates with the action of EXTL3 and chondroitin sulfates/dermatan sulfates with the action of CSGalNAcT-1. In this biosynthesis, the linkage region may be sulfated, but the role of these sulfations is still poorly understood.The objective of this work was to synthetize disaccharides of the linkage region and transfer trisaccharides, with the first aminosugar of the GAGs chains, variously monosulfated or not, in order to study the role of sulfations on the bifurcation enzymes.Different activation methods, microwaves and flow chemistry, were also tested to sulfate mono-, di- and trisaccharides
Books on the topic "Sucrose content"
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N, Jacobs G., ed. Suicide by sugar: A startling look at our #1 national addiction. Square One Publishers, 2009.
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Keith, Lierre. The vegetarian myth: Food, justice and sustainability. Flashpoint Press, 2009.
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Gameau, Damon. That Sugar Book: The Essential Companion to the Feature Documentary That Will Change the Way You Think about Healthy Food. Flatiron Books, 2015.
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United States Department of Agricult and William Bradford 1859-1946 Alwood. Enological Studies. the Occurrence of Sucrose in Grapes. the Sugar and Acid Content of Different Varieties of Grapes, Sampled at Frequent Intervals During Ripening and at Full Maturity; Volume No. 140. Creative Media Partners, LLC, 2023.
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United States Department of Agricult and William Bradford 1859-1946 Alwood. Enological Studies. the Occurrence of Sucrose in Grapes. the Sugar and Acid Content of Different Varieties of Grapes, Sampled at Frequent Intervals During Ripening and at Full Maturity; Volume No. 140. Creative Media Partners, LLC, 2023.
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Moss, Michael. Salt Sugar Fat: How the Food Giants Hooked Us. Penguin Random House, 2013.
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Moss, Michael. Salt, Sugar, Fat: How the Food Giants Hooked Us. Ebury Publishing, 2013.
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Moss, Michael. Salt Sugar Fat: How the Food Giants Hooked Us. Ebury Publishing, 2014.
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Brick, Scott, and Michael Moss. Salt Sugar Fat: How the Food Giants Hooked Us. Brand: Random House Audio, 2013.
Find full textBook chapters on the topic "Sucrose content"
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Thi Thuy Loan, Huynh, Lai Thi Hien, Ho Thi Ngọc Nhung, Nguyen Thi Thuy Duyen, Nguyen Le Ha, and Huynh Kim Phung. "Optimizing the absorption process by using isomalt sugar to replace sucrose in the production process of dried cashew apple for dieters." In Green Transformation in the Context of Global Change. CRC Press, 2025. https://doi.org/10.1201/9781003602941-48.
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ROSSON, DAN P., and THOMAS P. CHIRPICH. "The Sucrose Content of Breakfast Cereals." In Practical Biochemistry for Colleges. Elsevier, 1989. http://dx.doi.org/10.1016/b978-0-08-036140-6.50071-1.
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Sica, Pietro. "Sugarcane Breeding for Enhanced Fiber and Its Impacts on Industrial Processes." In Sugarcane [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.95884.
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For centuries, sugar has been virtually the only commercialized product derived from sugarcane. Traditionally, sugarcane breeding programs focused exclusively on the increase of the sucrose content, abandoning characteristics such as biomass yield and fiber content. Recently, sugarcane gained prominence also for its potential in terms of biomass production. As a result, some sugarcane breeding programs began to look for ways to increase fiber content and biomass yield instead of sugar content. In the 1980s, Alexander created the concept of energy cane. Here we review the changes in the sugarcane breeding programs related to enhanced fiber instead of sugar content. Compare the energy generation of energy cane with other biomass crops. Also, the recent changes in the biomass and biofuels scenario, focusing on topics as 2G ethanol and the RenovaBio program, from the Brazilian Government, which will give carbon credits to biofuels. Although several studies demonstrate its potential for biomass production, energy cane is still a new technology on an experimental scale and has been struggling to reach and establish on a commercial scale. However, policies and new technologies are increasing the demand for lignocellulosic material. Therefore, this chapter connects these points and shows the potential of this new plant material for the coming years.
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Agus, Ali, and Agussalim Agussalim. "Approach for the Domestication and Propagation of Stingless Bees." In Advances in Environmental Engineering and Green Technologies. IGI Global, 2023. http://dx.doi.org/10.4018/978-1-6684-6265-2.ch004.
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Domestication and propagation in stingless bees is called meliponiculture. The aims of meliponiculture are to make it easier to control the colonies health and development and to make it easy when harvesting stingless bee products (honey, bee bread, and propolis), furthermore, for advanced study and development like multiple colonies, to produce honey, bee bread, and propolis. Therefore, this paper focuswa on stingless bees Tetragonula laeviceps: the domestication and propagation technique, production of stingless bee products (honey, bee bread, and propolis), the daily activity of workers (foragers), the chemical composition (glucose, fructose, sucrose, reducing sugar, moisture, protein, ash, phenolic, flavonoid, vitamin C, antioxidant activity, minerals content, and amino acids) of honey from T. laeviceps, the pests and the challenges in meliponiculture of stingless bees.
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Rodríguez-Sulbarán, Pedro J., Claudio A. Lugo, Manuel A. Perez, et al. "Dry Reforming of Methane on LaSrNiAl Perovskite-Type Structures Synthesized by Solution Combustion." In Advanced Solid Catalysts for Renewable Energy Production. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-3903-2.ch009.
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A comprehensive study of the effect of the combustion fuel (i.e., glycine and sucrose), ignition source (i.e., furnace and microwave radiation), and nickel content is carried out for the dry reforming of methane (DRM) using La0.6Sr0.4NiyAl1-yO3 (LaSrNiAl) (y = 0.1; 0.2 and 0.3) perovskite-type catalyst precursors synthesized by solution combustion synthesis (SCS). The composition of the catalyst precursor and the combustion fuel rather than the ignition source affected markedly the crystalline phase composition, crystallite size, morphology, specific surface, and reducibility. Those changes are also reflected in the catalytic performance of the SCS-prepared catalyst in the reaction of DRM. The results clearly show that the SCS approach can effectively tune the dry reforming of methane and the reverse water-gas shift reactions by varying the combustion fuels.
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Nishinari, Katsuyoshi, A. T. Tomohisa, Y. Aka, et al. "Gelation of food macromolecules: effects of sugars on the gelation of agarose and mixtures of konjac glucomannan and carrageenan." In Gums and Stabilisers for the Food Industry 7. Oxford University PressOxford, 1994. http://dx.doi.org/10.1093/oso/9780199634651.003.0031.
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Abstract Effects of sugars on gelation of agarose were studied by differential scanning calorimetry (DSC) and dynamic viscoelastic measurements. It was suggested that the number of junction zones was increased, and that the size of junction zones became smaller by the addition of sucrose. As a result of this, the rotational freedom of parallel links which constitute a zipper was decreased. The increment of melting or setting temperature per unit concentration of sugars was correlated linearly with the dynamic hydration number of the sugars. Small and large deformation rheological measurements on mixed systems of kappa-carrageenan and konjac glucomannan with different molecular weights suggested that gels of this mixture consist of a carrageenan network strengthened by weak interaction of konjac glucomannan with carrageenan. carrageenan-rich mixtures (CAR content&gt; 70%) showed two exothermic peaks in the cooling DSC curves.
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Ikegbunam, Nchedochukwu Clara, Walter John Okwong, Emeka Osayi, Bibian Aziagba, Kelechukwu Kennedy Ndubueze, and Jude Ugwoke. "Compositional Analysis of the Physico-Chemical Properties of Honey Samples From Imo and Enugu States, Nigeria." In Advances in Environmental Engineering and Green Technologies. IGI Global, 2024. http://dx.doi.org/10.4018/978-1-6684-7801-1.ch005.
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The addition of artificial substances to honey in order to increase its volume or lower its cost is rampant. This study analyzes eleven honey samples from Enugu and Imo States, Southeastern Nigeria, for physico-chemical attributes such as pH, moisture, protein, fats, ash, polyphenols, free acidity, HMF, conductivity, and sugar. The pH of the samples ranged from 2.82 to 3.86. Moisture content varied from 4.60% - 14.81%; ash 0.25 -2.53%; protein 0.77- 1.45%; fat 0.01 - 0.23%; polyphenol 1.24 - 11.23%; free acidity 17.52 - 19.04 meq/kg; HMF 50.03 - 103.33 mg/kg. The sugar analyses revealed that all honey samples contained the recommended amount of sugar for quality honey, with significant differences across locations. However, sucrose values slightly exceeded the recommended limit of 5 g for quality honey. Conductivity and HMF values were also above the recommended standard. Most tested parameters conform to international standards, making the honey suitable for human consumption.
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Zulato, Gabriele, Renan Augusto Coghi, and Mariana Borges de Lima Dutra. "Evaluation of the physical-chemical quality of honey without inspection registration sold in municipalities of Itapira and Mogi Guaçu, State of São Paulo." In Engineering and its advancements. Seven Editora, 2024. http://dx.doi.org/10.56238/sevened2024.004-026.
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Honey, is The valuable food, but its quality can be compromised by adulteration. Brazilian legislation defines quality parameters for honey, including its chemical composition and physical-chemistry characteristics. The objective of this work is to verify whether commercial honeys are not registered in the municipalities of Itapira and Mogi Guaçu meet these legal standards, with the purpose of evaluating the quality and authenticity of the product. In this study, 10 samples of unlabeled honey were collected from the municipalities of Itapira -SP and Mogi Guaçu -SP. Physicochemistry analysis were carried out covering reducing sugars, moisture, soluble solids, Ash, apparent sucrose, pH, acidity and color, in addition to adulteration tests, Lugol, Lund and Fiehe reactions, with all analysis being carried out in triplicate. The methodologies adopted followed the recommendations of the Adolfo Lutz Institute. The results were submitted I'm statistical analysis with ANOVA/Tukey test, considering a significance level of 5%. The main results revealed that one of the samples contained reducing sugars below the limit for floral honey, suggesting adulteration. For humidity, disappear samples exceeded the acceptable limit, which affects the quality and durability of the honey. The results obtained from soluble solids are in accordance with works found in the literature. At the mineral impurities were found in the ash content analysis. Some honeys showed high levels of apparent sucrose and acidity, raising concerns about adulteration and impact on flavor and quality. There was variation in the acidity content of the samples, but this remained in the typical range for honeys. Furthermore, analysis of colorimetric parameters revealed significant variations in the L*, a* and b* components for all samples. For adulteration tests, in the Lugol reaction, only 40% of the samples presented negative results, suggesting The high level of adulteration by starch or dextrins . Regarding the Lund reaction, only 30% of the samples revealed protein precipitate within the expected range, indicating that 70% of the samples may have been adulterated by the addition of water or another diluent. In the Fiehe reaction, 70% of the samples demonstrated positive results, indicating adulteration due to the addition of sugar syrups or overheating of the honey. Through the results obtained, it was concluded that compliance with legal standards varies considerably between samples.
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Dev Gautam, Rahul, Ravi Kumar, Ujala Kashyap, et al. "Genetic Improvement of Stevia: A Natural Non-Calorie Sweetener." In Plant Breeding - New Perspectives [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.105510.
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Stevia rebaudiana, a native of South America, is a perennial herb of the Asteraceae family, also known as a natural sweetener due to the presence of steviol glycosides (SGs) in the leaves. China is the largest producer and exporter of stevia, while Japan is the primary consumer. The increasing demand for natural low-calorie sweeteners in the medicine and food industry has increased the pressure over stevia cultivation. Still, its cultivation and region-specific agrotechnologies need to be developed. The major bottleneck in stevia production are the lack of region specific cultivation technologies, non-availability of quality planting material, and uncharacterized and not properly conserved plant genetic resources. All these constraints have limited the stevia production to some specific regions of the world. Development of high-yielding cultivars with enhanced SGs content using modern breeding techniques is of prime importance to meet its increasing demand. Among the glycosides present in the leaves, rebaudioside-A is the most desirable glycosides having 250–300 times sweeter than sucrose, while, after bitter taste is due to the presence of stevioside and dulcoside. Therefore, the development of varieties with high rebaudioside-A and low stevioside content is highly desirable. This chapter focused on the improvement of propagation methods, characterization and conservation of genetic resource in stevia and its utilization in crop improvement programs.
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Pompelli, Marcelo F., Diana Carolina Londoño Gómez, and Ana Milena Vásquez-Bettin. "Sugarcane and Energy cane, a valuable biofuel substitute for petroleum gasoline." In PLANTS: Physiology, crop production, and stress responses. Editora Científica Digital, 2025. https://doi.org/10.37885/250419154.
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This chapter examines the progressive role of sugarcane in sustainable biofuel production, highlighting the distinctions between first-, second-, and third-generation (1G, 2G, and 3G) ethanol. First-generation ethanol is derived from the fermentation of sugars in sugarcane juice, but this method is constrained by limited productivity and a tradeoff between sucrose and fiber content. Sec-ond-generation ethanol improves upon this by utilizing lignocellulosic residues such as bagasse and straw, enhancing energy yield per hectare without expanding land use. However, it requires complex pretreatment and enzymatic hydrolysis processes. Advances like deep eutectic solvents, mechanocatalysis, and engineered microbes are improving the feasibility of 2G ethanol. The third-generation approach targets non-food biomass sources such as marine algae and enhanced energy cane varieties, which offer high fiber content and adaptability to marginal environments. These 3G technologies promise carbon-neutral fuel but remain chal-lenged by high costs, energy-intensive hydrolysis, and the need for optimized microbial fermentation of diverse sugars. Energy cane emerges as a key transitional crop, offering superior yields (up to 180 tons per hectare), greater stress tolerance through robust rhizome systems, and multi-cycle productivity, thereby lowering operational costs and supporting bioelectricity co-generation. While 1G ethanol is well-established and 2G is commercially emerging, 3G holds the most transformative potential by addressing food security concerns, maximizing biomass conversion, and aligning with low-carbon economic goals. Ultimately, energy cane acts as a vital “green necklace” connecting traditional and future biofuel strategies, reinforcing Brazil’s potential leadership in global renewable energy transitions.
Conference papers on the topic "Sucrose content"
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Ranjan, Rajiv, and Shashank Tamaskar. "Prediction of Sugarcane Sucrose Content and Optimal Harvest Date Using Multi-Spectral Time Series Image Processing of Satellite Data." In IGARSS 2024 - 2024 IEEE International Geoscience and Remote Sensing Symposium. IEEE, 2024. http://dx.doi.org/10.1109/igarss53475.2024.10640589.
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Casu, Rosanne E., Anne A. Rae, Chris P. L. Grof, et al. "NEW GENES FOR INCREASING THE SUCROSE CONTENT OF SUGARCANE." In XXIst International Carbohydrate Symposium 2002. TheScientificWorld Ltd, 2002. http://dx.doi.org/10.1100/tsw.2002.772.
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Sundyreva, M. A., A. N. Rebrov, A. E. Mishko, and E. O. Lutsky. "The effect of sucrose concentration in the culture medium on the formation of abscisic acid and the activity of the photosynthetic apparatus of grape plants in vitro." In 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.240.
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An increase in sucrose in the medium increased the content of pigments, gene expression of the photosynthetic apparatus, growth processes, and H2O2, but decreased the quantum yield of photosynthesis. With a change in the sucrose content in the medium, the expression of ABA1 increased most intensively. 30 g/l of sucrose in the medium inhibited the expression of genes involved in the formation of ABA.
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Durães, Tiago, Miguel Azevedo, Fernanda Cosme, and Fernando M. Nunes. "Enzymatic Reduction of Sugar Content in Sucrose-Rich Fruit Products." In International Meeting Molecules 4 Life. MDPI, 2024. http://dx.doi.org/10.3390/msf2023023006.
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Kruzhkova, L. V. "EFFECT OF SUCROSE CONCENTRATION ON IN VITRO RHIZOGENESIS OF PROMISING A.ALNIFOLIA GENOTYPES." In Agrobiotechnology-2021. Publishing house RGAU-MSHA, 2021. http://dx.doi.org/10.26897/978-5-9675-1855-3-2021-77.
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The paper presents the data resulted from the studies for the effect of different concentrations of sucrose on in vitro rhizogenesis of A.alnifolia microcutting. It was found out the medium with higher sucrose content up to 30-40 g/l promoted root formation in A.Alnifilia microcutting and ensured rootability up to 47.6-70.0% depending on genotype.
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Leiqing Pan, Qibing Zhu, Renfu Lu, and J. Mitchell McGrath. "Detection of Sucrose Content of Sugar Beet by Visible/Near Infrared Spectroscopy." In 2013 Kansas City, Missouri, July 21 - July 24, 2013. American Society of Agricultural and Biological Engineers, 2013. http://dx.doi.org/10.13031/aim.20131619051.
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Pomytkin, N., S. Lugovcova, and V. Stupko. "INFLUENCE OF NUTRIENT MEDIUM CONTENT ON MICROTUBER FORMATION OF ZONED POTATO VARIETIES IN VITRO." In The state and problems of agricultural science in Yenisei Siberia. Krasnoyarsk Scientific Research Institute of Agriculture is a separate division of the Federal Research Center KSC SB RAS, 2024. http://dx.doi.org/10.52686/9785605087908_227.
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The dynamics of microtuber formation in six zoned potato varieties was studied on various media. The main component of the media that influences microtuber formation is sucrose (80 g/l). The addition of phytohormones to the medium did not have a significant effect on microtuber formation, with the exception of the Red Scarlett variety.
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Annunziata, Maria Grazia, Loredana F. Ciarmiello, Pasqualina Woodrow, Eugenia Maximova, Amodio Fuggi, and Petronia Carillo. "Durum wheat roots adapt to salinity remodelling the cellular content of nitrogen metabolites and sucrose." In International Scientific Symposium "Advanced Biotechnologies - Achievements and Prospects". Institute of Genetics, Physiology and Plant Protection, Republic of Moldova, 2020. http://dx.doi.org/10.53040/9789975566957.03.
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"Detection of Moisture, Soluble Solids, and Sucrose Content and Mechanical Properties of Sugar Beet by Hyperspectral Scattering Imaging." In 2014 ASABE Annual International Meeting. American Society of Agricultural and Biological Engineers, 2014. http://dx.doi.org/10.13031/aim.20141912563.
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da Silva, Thais, Vicent Baeten, and Sabine Danthine. "Sucrose Esters Potential as Oleogelators to Form Oleogels Using Different Structuration Routes." In 2022 AOCS Annual Meeting & Expo. American Oil Chemists' Society (AOCS), 2022. http://dx.doi.org/10.21748/nimt7116.
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Sucrose esters (SE) have been widely studied as emulsifiers to tailor fats' crystallization. Nevertheless, fewer studies have assessed the potential of SEs as oleogelators to structure oleogels. This study aimed to evaluate alternative routes that would improve the oleogelation capacity of commercial SEs with different HLB values and evaluate the physical properties of the oleogels with 10% of SE produced by different routes. Four SEs were evaluated (SP10-HLB2, SP30-HLB6, SP50-HLB11, and SP70-HLB15) using three oleogelations routes (traditional, ethanol, and foam-template). Those oleogels were evaluated according to their microstructure, melting behavior, polymorphism, mechanical properties, oil binding capacity, and mid-infrared. In general, only SP50 ethanol showed a solid-like structure using only 10% of SE. This sample presented a higher hardness (0.4±0.1N) and elastic modulus (4589±89Pa). SP70 showed a potential oleogel after foam-template approach due to the higher oil binding capacity among all SEs and routes. SP10 was the only SE utterly soluble in oil, although it formed a very liquid gel, and SP30 has not shown a potential route or oleogel structure for any of the routes tested. The higher potential of the oleogels with SP50 and SP70 using alternative routes can be attributed to the higher content of monoesters in these samples. Consequently, more H-bonds between triacylglycerols carbonyl groups and hydroxyl groups formed.
Reports on the topic "Sucrose content"
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Juvik, John A., Avri Bar Zur, and Torbert R. Rocheford. Breeding for Quality in Vegetable Maize Using Linked Molecular Markers. United States Department of Agriculture, 1993. http://dx.doi.org/10.32747/1993.7568764.bard.
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Recently, the vegetable corn industry has shifted from the use of traditional cultivars with the sugary1 (su1) endosperm mutation to newer hybrids homozygous for the shrunken2 (sh2) or sugary enhancer1 (se1) genes. With greater kernel sucrose content, these hybrids are preferred by consumers and retain sugar for longer post harvest periods, providing the industry with more time to marker products with superior quality. Commercialization has been hindered, however, by reduced field emergence, and the establishment of stands with heterogeneous uniformity and maturities. This investigation was conducted to identify key biochemical and physiological characteristics in sh2 and se1 maize kernels associated with improved emergence, and stand establishment; and in immature ears at fresh harvest maturity, properties associated with eating quality. The location of genes or QTL controlling these kernel characteristics and other traits were then mapped to specific chromosomal regions by their linkage to molecular markers using two segregating F2:3 populations. This database was used to compare the efficiency of marker-assisted selection of key alleles with phenotypic selection for trait improvement. A model designed to uncover and quantify digenic interaction was applied to the datasets to evaluate the role of epistasis in the inheritance of quantitative traits.
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Bennett, Alan, and Arthur Schaffer. Sucrose Metabolism in Developing Fruit of Wild and Cultivated Lycopersicon Species. United States Department of Agriculture, 1996. http://dx.doi.org/10.32747/1996.7613009.bard.
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The project focused on a strategy to enhance tomato fruit soluble solids by evaluating components of carbohydrate metabolism in fruit of wild tomato species that accumulate sucrose rather than hexose and have extremely high soluble sugar contents. The overall goal was to determine the extent to which sucrose accumulation contributes to elevated soluble solids levels and to understand the underlying genetic and biochemical basis of the trait. The research objectives were to evaluate near isogenic L. esculentum lines segregating for sucrose- and hexose-accumulation, determine the biochemical basis of sucrose accumulation and develop molecular genetic strategies to enhance sucrose accumulation in fruit. The inheritance of the sucrose accumulation gene (sucr) was evaluated in both L. chmielewskii and L. hirsutum and shown to be conferred by a single recessive gene in each species. Stable L. esculentum lines homozygous for the sucr gene from L. chmieliewskii and L. hirsutum were well characterized on a genetic and physiological basis and have been introduced into breeding programs to modify fruit sugar composition. The metabolic basis of sucrose accumulation was determined to result from the lack of sucrose hydrolytic capacity. The invertase gene was cloned and its analysis indicated that it is transcriptionally silent in sucrose-accumulating fruit. Transgenic plants expressing an antisense invertase gene were produced and shown to accumulate high levels of sucrose, confirming the role of invertase as the primary determinant of sucrose accumulation and demonstrating the feasibility of a general strategy to genetically engineer sugar composition.
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Sionov, Edward, Nancy Keller, and Shiri Barad-Kotler. Mechanisms governing the global regulation of mycotoxin production and pathogenicity by Penicillium expansum in postharvest fruits. United States Department of Agriculture, 2017. http://dx.doi.org/10.32747/2017.7604292.bard.
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The original objectives of the study, as defined in the approved proposal, are: To characterize the relationship of CreA and LaeA in regulation of P T production To understand how PacC modulates P. expansumpathogenicity on apples To examine if other secondary metabolites are involved in virulence or P. expansumfitness To identify the signaling pathways leading to PAT synthesis Penicilliumexpansum, the causal agent of blue mould rot, is a critical health concern because of the production of the mycotoxinpatulin (PAT) in colonized apple fruit tissue. Although PAT is produced by many Penicilliumspecies, the factors activating its biosynthesis were not clear. This research focused on host and fungal mechanisms of activation of LaeA (the global regulator of secondary metabolism), PacC (the global pH modulator) and CreA (the global carbon catabolite regulator) on PAT synthesis with intention to establish P. expansumas the model system for understanding mycotoxin synthesis in fruits. The overall goal of this proposal is to identify critical host and pathogen factors that mechanistically modulate P. expansumgenes and pathways to control activation of PAT production and virulence in host. Several fungal factors have been correlated with disease development in apples, including the production of PAT, acidification of apple tissue by the fungus, sugar content and the global regulator of secondary metabolism and development, LaeA. An increase in sucrose molarity in the culture medium from 15 to 175 mM negatively regulated laeAexpression and PAT accumulation, but, conversely, increased creAexpression, leading to the hypothesis that CreA could be involved in P. expansumPAT biosynthesis and virulence, possibly through the negative regulation of LaeA. We found evidence for CreAtranscriptional regulation of laeA, but this was not correlated with PAT production either in vitro or in vivo, thus suggesting that CreA regulation of PAT is independent of LaeA. Our finding that sucrose, a key ingredient of apple fruit, regulates PAT synthesis, probably through suppression of laeAexpression, suggests a potential interaction between CreA and LaeA, which may offer control therapies for future study. We have also identified that in addition to PAT gene cluster, CreA regulates other secondary metabolite clusters, including citrinin, andrastin, roquefortine and communesins, during pathogenesis or during normal fungal growth. Following creation of P. expansumpacCknockout strain, we investigated the involvement of the global pH regulator PacC in fungal pathogenicity. We demonstrated that disruption of the pH signaling transcription factor PacC significantly decreased the virulence of P. expansumon deciduous fruits. This phenotype is associated with an impairment in fungal growth, decreased accumulation of gluconic acid and reduced synthesis of pectolytic enzymes. We showed that glucose oxidase- encoding gene, which is essential for gluconic acid production and acidification during fruit colonization, was significantly down regulated in the ΔPepacCmutant, suggesting that gox is PacC- responsive gene. We have provided evidence that deletion of goxgene in P. expansumled to a reduction in virulence toward apple fruits, further indicating that GOX is a virulence factor of P. expansum, and its expression is regulated by PacC. It is also clear from the present data that PacC in P. expansumis a key factor for the biosynthesis of secondary metabolites, such as PAT. On the basis of RNA-sequencing (RNA-seq) analysis and physiological experimentation, the P. expansumΔlaeA, ΔcreAand ΔpacCmutants were unable to successfully colonize apples for a multitude of potential mechanisms including, on the pathogen side, a decreased ability to produce proteolytic enzymes and to acidify the environment and impaired carbon/nitrogen metabolism and, on the host side, an increase in the oxidative defence pathways. Our study defines these global regulatory factors and their downstream signalling pathways as promising targets for the development of strategies to fight against this post-harvest pathogen.