Dissertations / Theses on the topic 'Sucrose content'

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.

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.

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

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.

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.

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 Melo_LauroLuisMartinsMedeirosde_D.pdf: 959944 bytes, checksum: ee44eced3d2acbc8900f5441b96782b5 (MD5) 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

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

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)

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

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

Le gel est un des facteurs majeurs limitant l'aire de répartition des végétaux. Il a pour conséquence de limiter l'efficience de la circulation de sève brute par formation d'embolie dans les vaisseaux du xylème. Lorsqu'il y a formation de glace dans les tissus, les cellules vivantes peuvent également être lysées dans les organes lignifiés, et dans les bourgeons. Pour pallier cela, différents mécanismes de résistance sont développés pour limiter la formation d'embolie ou la résorber, pour augmenter transitoirement la tolérance à la formation de glace dans les tissus et pour éviter d'exposer les bourgeons et jeunes feuilles aux gels printaniers tardifs. Ces différents traits ont été caractérisés pour onze espèces communes ayant des limites altitudinales potentielles contrastées. Puis la physiologie de l'acclimatation au gel chez Juglans regia L. a été caractérisée, essentiellement à travers les relations entre humidité pondérale, contenu en sucres solubles, climat et levée de dormance. L'ensemble de ces données a permis d'élaborer un modèle prédictif de la résistance au gel en relation avec la physiologie de l'arbre qui pourrait, couplé avec d'autres modèles simulant la période estivale, permettre d'estimer la conjonction de différents stress sur le potentiel de résistance.

L’objet de ce travail est d’étudier le comportement de l’acier inoxydable nuance 304L (AISI SS304L) en contact avec un milieu jus de canne contenant des particules en suspension (sable, roche, etc. ). Cet acier est particulièrement utilisé dans l’industrie sucrière mauricienne. Le jus de canne est acide (pH moyen égal à 5. 5) à l’extraction. Ceci est dû en grande partie à la présence d’une grande variété d’acides (« aconitique, citrique, malique, oxalique, glycolique, mesaonique, tartarique, succinique, fumarique et syringique »). Ce jus de canne contient aussi plusieurs types de microorganismes qui sont très actifs et qui abaissent le pH dans le temps. Des minéraux en solution dans l’eau tels que le chlorure de sodium, NaCl, des sulfates, ainsi que la silice présents dans le jus vont également avoir un rôle néfaste sur les mécanismes associés à l’endommagement de la surface. L’endommagement de la surface de l’acier 304L est donc dû : à un mécanisme d’usure chimique ainsi qu’à un mécanisme mécanique (tribocorrosion). Pour évaluer la perte de masse de l’échantillon SS304L en contact avec le jus de canne et déterminer l’effet de synergie, des simulations expérimentales en : Corrosion, Erosion Corrosion et Abrasion Corrosion ont été réalisées. Les paramètres : pH, angle d’impact du fluide, vitesse du fluide, débit du fluide, taille des particules, concentration de particules, sont soigneusement pris compte dans les études expérimentales. Des mesures électrochimiques couplées avec des mesures en Emission Acoustique (EA) ont été mises en oeuvre. Elles ont permis de suivre la vitesse de corrosion ; l’émission acoustique a contribué pour confirmer la bonne corrélation du suivi électrochimique et a apporté un élément supplémentaire d’un point de vue énergétique et spectral. En effet l’étude spectrale a montré l’intérêt de l’émission acoustique et a permis d’établir une classification des mécanismes d’usure associés à cette étude. Enfin, un effet de synergie entre la corrosion et l’abrasion est mis en évidence : cela a permis d’en déduire que l’endommagement maximal se situe à un angle d’incidence de 90 degré<br>The main objective of this research study is to assess the behaviour of stainless steel AISI 304L in contact with sugar cane juice. Stainless steel grade 304L is largely used in the sugar cane industry but the acidic nature of sugar cane juice pose a serious challenge in maintaining the life span of vital components. Sugar cane juice is acid having a pH value of around 5. 5 at extraction. This acidic property is accounted for by the presence of a variety of acids namely : aconitic, citric, malic, oxalic, glycolic, mesaonic, tartic, suceinic, fumaric and syringic in sugar cane juice. In addition to these acids there are approximately 50 different kind of microorganism present in the green cane and act as a contributor to a rather quick drop in pH (pH~3. 1) of the cane juice once extracted. The more so, several minerals like water, salt, sulphate and abrasive particulates and silica are also present throughout the process line and are other contributor in the surface degradation wear mechanism. Faced with all these adverse elements, it is therefore fundamental to investigate thoroughly in the wear corrosion mechanism and bio corrosion on stainless steel grade 304L. To evaluate the mass loss ; corrosion, corrosion erosion and corrosion abrasion experimentations were carried with the help of both potentiostat and acoustic emission in a sterilised juice and none sterilised juice. Analysis of experimental data in terms of weight loss due to corrosion and corrosion abrasion plotted against the acoustic emission RMS data have shown clearly effect of synergy and produces the worst adverse effect on the surface at 90 degree impact

Des études antérieures ont mis en évidence que le transfert de solutés neutres à travers des membranes est influencé par la présence d'ions en solution. Ainsi, la connaissance des interactions multiples à l'échelle nanométrique, entre le polymère, l'eau et les solutés (ions, espèces organiques) constituent un verrou pour l'amélioration des performances des procédés membranaires. Dans cette étude une approche multi-échelle fondamentale est proposée, combinant des outils théoriques et expérimentaux, afin d'obtenir les paramètres microscopiques et macroscopiques caractérisant les interactions étudiées pour différentes compositions ioniques. Plus précisément, il s'agit de comprendre comment les ions affectent le transfert d'un soluté organique. Dans un premier temps, certaines propriétés caractérisant l'hydratation des ions sont calculées et comparées aux flux de diffusions de sucres à travers des membranes de Nanofiltration et échangeuses d'ions obtenus pour différentes compositions ioniques. Dans un deuxième temps, des systèmes constitués d'une membrane échangeuse de cations (CMX) équilibrée avec différents cations ainsi que le glucose hydraté sont modélisés en utilisant une approche combinée Mécanique Quantique/ Mécanique Moléculaire. Cette approche a permis d'étudier la solubilité du sucre dans la matrice polymère ainsi que les interactions polymère-polymère comme l'énergie de cohésion. Enfin, l'influence des ions sur les caractéristiques physiques de la membrane CMX est étudiée en utilisant diverses méthodes expérimentales comme la détermination des angles de contacts et des spectres IR ou la mesure de la température de solidification par DSC. Les propriétés vibrationnelles sont également calculées dans le cadre de la théorie de la fonctionnelle de la densité (DFT). L'ensemble de ces données sont comparées avec les grandeurs de transport afin de valider les mécanismes moléculaires proposés. Ce travail montre que la nature des contre-ions de la membrane modifie l'énergie de cohésion entre les fragments de la membrane. Ainsi, l'énergie de cohésion influe sur la diffusion des composés organiques neutres à travers les membranes<br>Previous works have shown that the transfer of neutral solutes through membranes is influenced by the presence of ions in solution. In the framework of process intensification, the knowledge of the molecular mechanisms involved is of fundamental importance to increase and predict the process performances. The aim of this Thesis is to use a combined quantum/molecular computational approach and experimental methodologies to better understand how ions can affect the solute flux. In the first part of the work, some properties of ions in solution are computed and compared with sugar fluxes through membranes for nanofiltration and electrodialysis. In the following, systems composed of Cation-exchange membrane equilibrated by different counter-ion and hydrated glucose are examined by Quantum Mechanics/Molecular Mechanics. This is done mainly to investigate the sugar solubility in the polymer matrix and diffusion related interactions like polymer chain-chain cohesion energy. In the last part, contact angle, differential scanning calorimetry and Infra-Red spectra are measured to characterize the physical properties of the membrane and possible influence of the counter-ion on cation exchange membrane. This work shows that the nature of the counter-ions modifies the cohesion energy between the membrane polymer fragments. In its turn, the cohesion energy affects the diffusion of neutral organic compounds through the membranes

Les effets du changement climatique ont d’ores et déjà été observés sur la vigne : avancement des stades de développement, augmentation des teneurs en alcool des vins, baisse excessive de leur acidité. Une des voies d’adaptation possible de la viticulture est la création de nouvelles variétés. J’ai caractérisé la variabilité phénotypique de 120 descendants de croisements entre Riesling (RI) et Gewurztraminer (GW) pour (1) les stades de développement, décrits à l’aide de sommes de températures (2) la capacité à accumuler des sucres dans les raisins (3) les paramètres de l’acidité des raisins. L’utilisation de marqueurs moléculaires sur l’ADN a permis de mettre en évidence des relations entre données génétiques et phénotypiques pour tous les caractères étudiés (QTLs ou Quantitative trait loci). La principale conclusion est que la variabilité génétique pour les paramètres de l’acidité des raisins est la voie à valoriser en priorité pour l’adaptation de la vigne au changement climatique<br>The effects of climate change have already been observed on the grapevine : advance of phenological stages, increase in the alcohol content of the wines, excessive decrease of their acidity. Breeding new varieties is one of the possible means of adaptation. I have characterized the phenotypic variability of 120 genotypes, offspring from crossings between Riesling (RI) and Gewurztraminer (GW)for (1) the developmental stages, described with heat sums (2) the ability to accumulate sugars in the berries (3) the parameters for acidity. The use of DNA molecular markers allowed the detection of quantitative trait loci (QTLs) for all the traits studied. The main conclusion is that the genetic variability for the parameters determining the acidity of the berries is the most promising for the adaptation of grapevine cultivation to climate change

L’Organisation mondiale de la Santé recommande aux individus de limiter leur consommation d’aliments sucrés dans le but de prévenir le développement des maladies chroniques. En santé publique, peu de recherches ont tenté d’identifier les facteurs individuels et contextuels qui peuvent influencer conjointement la consommation de ces aliments. Or, de telles connaissances seraient utiles pour guider les interventions nutritionnelles visant à en réduire la consommation. L’objectif de cette thèse est d'étudier les facteurs reliés au comportement et les contextes associés à la consommation quotidienne d’aliments sucrés chez des adultes vivant dans un milieu urbain occidental. Cette étude a été menée auprès d'une communauté moyen-orientale établie dans la Ville de Montréal. Les aliments sucrés ont été définis comme étant les glucides raffinés dont la teneur en sucres totaux dépasse 20 % de l’énergie totale. Lors de l’étape exploratoire (N = 42), un rappel de 24 heures a permis d’identifier les sources d’aliments sucrés et de déterminer l’apport quotidien en sucres totaux de cette communauté. Une étude qualitative descriptive a été privilégiée et un cadre écologique a guidé la réalisation d’entrevues semi-dirigées sur les contextes de consommation (N = 42). Une analyse de contenu employant des procédures de codage initial et focus a mené à l’élaboration d’un instrument de mesure quantitatif sur les contextes de consommation. Cet instrument a été soumis à un pré-test (N = 20), puis administré à l’échantillon principal (N = 192). Une analyse factorielle exploratoire a permis de préciser les contextes de consommation. Les facteurs individuels mesurés incluent les données sociodémographiques, les symptômes dépressifs, la maîtrise de soi, l’assoupissement de jour, les perceptions ainsi que l’hémoglobine glycosylée. La consommation quotidienne de sucres totaux a été mesurée par un questionnaire de fréquence alimentaire (N = 192). Une analyse de régression multivariée employant le modèle linéaire généralisé (distribution de type gamma et lien logarithmique) a été effectuée pour mesurer les relations entre les contextes de consommation, les facteurs individuels et la consommation de sucres totaux, en contrôlant l’âge et le sexe. L’apport quotidien en sucres totaux de l'échantillon est de 20,3 %, ce qui s’apparente aux apports des Canadiens et des Québécois. La consommation quotidienne moyenne est de 76 g/j. Les analyses qualitative et factorielle ont permis d’identifier un ensemble de 42 contextes de consommation regroupés en sept domaines (Actes et situations de grignotage, Stimuli visuels, Besoins énergétiques, Besoins émotionnels, Indulgence, Contraintes, Socialisation). La consommation quotidienne de sucres totaux est supérieure chez les hommes (B = 0,204, ES = 0,094, p = 0,03). Les facteurs positivement associés à la consommation sont le grignotage (B = 0,225, ES = 0,091, p = 0,01), la prise de dessert (B = 0,105, ES = 0,036, p = 0,001) ainsi que les symptômes dépressifs (B = 0,017, ES = 0,094, p = 0,03). L’âge (B = -0,01, ES = 0,004, p = 0,02), l’indulgence (B = -0,103, ES = 0,052, p = 0,05) et l’auto-modération (B = -0,121, ES = 0,042, p = 0,001) montrent, pour leur part, une association négative. Cette étude a privilégié une méthodologie mixte et a permis de développer une mesure innovatrice pour étudier les facteurs contextuels associés à la consommation d’aliments sucrés. Ceux-ci ont été analysés conjointement avec les facteurs individuels. Afin d'encourager les individus à réduire leur consommation de sucres totaux lorsque nécessaire, les initiatives en santé publique devraient en effet cibler les contextes de consommation de même que les facteurs individuels.<br>The World Health Organization recommends that individuals reduce their consumption of sweet foods and drinks to prevent chronic diseases. Research in public health has not generally sought to elucidate the environmental and individual factors that may jointly influence sweet food consumption. Such knowledge would be relevant, however, in supporting interventions on sweet food consumption. The aim of this thesis was to examine contextual and individual factors associated with daily consumption of sweet foods in adults living in a western urban setting. An established Middle Eastern community in Montreal was the setting for this study. Sweet food was defined as refined carbohydrates that contain more than 20% of total energy from total sugars. In a preliminary step (N = 42), 24-hour recalls enabled the identification of sweet food sources and the measurement of daily intake of total sugars from total energy intake. The context of sweet food consumption was studied through a qualitative descriptive study. An ecological conceptual framework was used to frame the context of sweet food consumption and thus to guide the collection of semi-structured interviews (N=42). Content analysis using open and focused coding techniques was used to inform the development of a quantitative measure to investigate the context of sweet food consumption. This measure was pilot-tested on 20 individuals and administered to the main sample (N = 192). Contextual domains were clarified using exploratory factor analysis. Individual factors measured included depressive symptoms, mastery, sociodemographic factors, perception, daytime sleepiness and HbA1C. A food frequency questionnaire was used to measure daily intake of sweet food (N = 192). Sweet food consumption followed a gamma distribution. Multivariate regression analysis using the generalised linear model (gamma distribution and log-link function) was used to estimate the associations between contextual and individual factors and consumption of sweet food, accounting for covariates (gender and age). Total sugar consumption was 20,3 % of total energy, similar to the average intake of the population of Quebec and Canada. Daily consumption of total sugars averaged 76 g/day. Qualitative analyses and factor analysis led to the identification and refinement of a 42-item contextual measure with items grouped into seven domains (emotional needs, snacking, energy demands, socialisation, visual stimuli, indulgence and constraints). Consumption of total sugars was higher amongst males (B = 0,204, SE = 0,094, p = 0,03). Domains positively associated with total sugar consumption included eating dessert (B = 0,105, SE = 0,036, p = 0,001), snacking (B = 0,225, SE = 0,091, p = 0,01) and depressive symptoms (B = 0,017, SE = 0,094, p = 0,03). Indulgence (B = -0,103, SE = 0,052, p = 0,05), self-moderation (B = -0,121, SE = 0,042, p = 0,001), and age (B = -0,01, SE = 0,004, p = 0,02) were negatively associated with sugar consumption. This mixed-methods study developed a novel measure to study the factors associated with sugar consumption. Individual and contextual factors were jointly associated with consumption of sweet foods. Contextual as well as individual factors should be jointly targeted by public health efforts to support individuals in limiting their consumption of sweet foods, as necessary.