Effects of physico-chemical parameters of a model wine on the binding of γ-decalactone on bovine serum albumin

Abstract To understand the effect of temperature, pH and the composition of alcoholic beverages in flavour-protein interactions, the binding of γ-decalactone to bovine serum albumin (BSA) was investigated using the equilibrium dialysis method. Thermodynamic analysis revealed that the affinity of aroma compound for BSA is higher at 10 °C than at 20 and 30 °C, while the number of binding sites (n = 6–7) is not modified at the three temperatures. pH did not have any appreciable effect on flavour binding in the presence of ethanol, but it was observed that a decrease of 1.8 pH unit reduces binding by 40% in its absence. The presence of ethanol has no effect on the number of binding sites and on…

Determination of volatiles and sensory profile in grape juices from Gamay

The effect of sugars and pectin on flavour release from a fruit pastille model system

International audience

Influence of Mannaproteins from Yeast on the Aroma Intensity of a Model Wine

Abstract The influence of mannaproteins released from yeast cell walls during alcoholic fermentation on the volatility of aroma substances was investigated in a model wine. After the characterization of macromolecules (substrates), two techniques have been used to study the interactions with aroma compounds: headspace analysis and an equilibrium dialysis method. The assumed effects of these macromolecules from yeasts on the fixation of volatile compounds were demonstrated. The physico-chemical interactions between aroma substances and mannaproteins depended on the nature of volatile compounds. Protein concentration in substrates was an important factor in their binding capacity. The retenti…

Proposed alternative phase ratio variation method for the calculation of liquid–vapour partition coefficients of volatiles

International audience; The phase ratio variation PRV method is a classical way to determine the partition coefficients of volatile compounds between their solution and vapour phases in a variety of circumstances. However, some results obtained by this method can be disappointing. A new PRV equation in which the initial liquid-phase solute concentration is replaced by the liquid-phase solute concentration at equilibrium is proposed. This proposed PRV equation is a second-order polynomial equation. To thoroughly examine the possible modes of calculation, noisy dummy data were generated using both the classical, first-order PRV model (PRV1) and the proposed, second-order model (PRV2). Thus, p…

Effet de la variété sur les teneurs en métabolites secondaires dans les farines de pois

National audience

Optimisation de l'aromatisation d'un yaourt à 0 % de MG

National audience; Pour les technologues de l’agro-alimentaire, mettre au point un yaourt sans matière grasse dont la perception sensorielle réponde aux attentes du consommateur est un réel challenge. L’absence de matière grasse entraîne en effet, des modification de la texture et de la flaveur du produit. Pour pallier à ces modifications dans le yaourt aux fruits, des agents de texture sont apportés via la préparation de fruits sur sucre. Des mélanges d’amidon, de pectine et de caroube sont généralement utilisés avec des édulcorants : fructo-oligosaccharides, aspartame et acésulfame. La méthodologie des plans d’expériences a été utilisée pour concevoir treize préparations de fruits de comp…

Quantitative structure-property relationships approach of aroma compounds behaviour in polysaccharide gels

International audience; Pectin and carrageenan are common used thickeners in fat free foods. The aim of this work was to study separately and to compare their respective effects on the aroma release, in order to investigate the nature of involved interactions. In this way, we studied the influence of the chemical structure of 13 aroma compounds on retention/release equilibrium between vapour phase and gels using QSPR tools. Six descriptors are involved in the best obtained QSPR equations, and three of them appeared to play a critical role in the behaviour of aroma compound. Our results put forward the role of polar effects on the retention of odorant molecules in both iota-carrageenan and p…

Water and temperature contribution to the structuration of starch matrices in the presence of flavour.

The effect of hydrothermal treatments and flavours addition on starch structure and its physical properties were studied. Native wheat starch was treated at 2 different hydrations (water-starch ratios: 50/50 and 80/20 g w/w) and temperatures (65 and 85 °C) in the presence of flavours (ethyl hexanoate and 2-hexanone). The freshly prepared samples were subjected to DSC and flavour analysis. Flavour inclusion complex could not be detected by DSC, however the result of flavour analysis proved that there were flavours interactions with starch. Both ethyl hexanoate and 2-hexanone interacted with starch at similar rates. The highest flavour loss was found in the samples at high hydration and heate…

QSAR/QSPR approach of aroma compounds behaviour in food products

National audience; Fat and flavour are important factors in food acceptance and can affect the partitioning of hydrophobic flavour molecules. Most investigations on the release of flavour of fat-free yoghurts contain multiple thickeners. The addition of thickeners separately to fat-free yoghurt has not been extensively studied. For this reason, the aim of this work was to study the effects of different thickeners (starch and pectin) on the aroma release when added separately via a model fruit preparation to industrial fat-free yoghurt. After aromatisation of the yoghurt, and then a seven-day storage period, headspace analysis using solid phase micro extraction (SPME) was carried out. To eva…

Sorption of aroma compounds to oak wood in wine ageing conditions

National audience

Developing sustainable food : the role of consumer liking in optimization of pea yogurt

International audience; In the development of new food consumers’ acceptability is a critical factor. This study aimed at evaluating the possibility to introduce pea proteins as new fermented food. For this purpose, mixtures of cow and pea milks with different ratios of pea (0, 10, 20, 30, 40 and 100%) were fermented with French commercial yogurt-ferment. Consumer acceptability in two European countries: France (Western Europe) and Bulgaria (Southeastern Europe) was investigated. 60 Bulgarian and 70 French panelists were asked to rate: overall acceptability, appearance, odor, taste and texture on a hedonic scales going from 1 (I do not like at all) to 7 (I like very much). The ANOVA showed …

Retention and release behaviours of aroma compounds in dairy and pectin gels: the role of structural features

Fermentation des protéines végétales : atouts organoleptique et nutritionnel

Référence : 201511122426; Du fait de l’augmentation de la population de la planète, la production de protéines pour l’alimentation des populations et l’évaluation de la qualité de ces protéines pour satisfaire les besoins de l’Homme pourraient devenir des questions majeures dans les décennies à venir pour l’ensemble du monde. Le développement de nouveaux aliments optimisant l’apport protéique d’origine végétale parait également important dans certaines situations (personnes âgées, sportifs…) où les besoins nutritionnels sont modifiés au plan quantitatif et qualitatif. De nombreux problèmes ont été identifiés suite à l’incorporation de protéines végétales dans nos aliments. En particulier, d…

Improvement of partition coefficients determination of aroma compounds in food matrices by the phase ratio variation method

The Phase Ratio Variation (PRV) method is a very valuable method commonly used for liquid/vapor partition coefficients data acquisition of aroma compounds. Nevertheless, some limits are linked to this method, especially for volatile compounds. A careful examination of the PRV equation leads us to propose the following expression: 1/Cvap-real =(nliq/n0) x 1/Cvap-ideal = (nliq/n0) x (1/KC0 + (1/Co) b), We performed an examination for two cases of K values (K1=0.001 and K2=0.05), putting forward that a carefully choice of b range values is crucial for reliability of the regression calculation 1/A versus b.

Aroma release in fat free dairy gels added or not added with pectin

International audience; The replacement of fat by thickeners in fat free yogurts leads to an important modification of aroma compounds partitioning, with an impact on aroma perception (Guichard, 2002). Investigation of retention/release equilibriums allows a good understanding of aroma compounds behaviour depending on food composition. The aim of this work is to study the influence of matrix composition on aroma release.

The salivary reactor: an innovating tool for the categorization of food products through their aroma and taste compounds release profiles

ISBN-10: 3-938896-38-9 ISBN-13: 978-3-938896-38-9

Screening of lactic acid bacteria for fermentation of a mix of cow and pea protein

Screening of lactic acid bacteria for fermentation of a mix of cow and pea protein. Vitagora - 9. international taste-nutrition-health congress

Effects of texture and temperature on the kinetic of aroma release from model dairy custards

http://www.sciencedirect.com/science/article/B6T6R-4YYRMXD-2/2/9ac9167b05d21ef9ff6dcce684696e13 http://www.elsevier.com/locate/foodchem; International audience; The structure of a foodstuff, and its perceived texture, are important characteristics involved in the sensory availability of flavour compounds released during the food consumption. This study identifies the effect of texture on the dynamic release of aroma compounds under simulated oral conditions (temperature and shearing). Two custard desserts, with two levels of texture but the same composition, flavoured with four aroma compounds, were analysed. The rheological behaviour of the custards and the release of aroma compounds (SPME…

Retention-release equilibrium of aroma compounds in polysaccharide gels: study by quantitative structure-activity/property relationships approach

The nature and amount of constituents in food greatly influence aroma release. Pectins and carrageenans are common used thickeners, but their effect on the release of aroma compounds has been studied more frequently for non- homogeneous products than for thickeners separately. The purpose of this work was to study and compare their respective effects in simple model systems. In this way, the release of 13 aroma compounds was analysed by headspace analysis at equilibrium in pure water, i-carrageenan and pectin gels. To evaluate the influence of the chemical structure of aroma com- pounds on retention/release equilibrium between vapour phase and gels, we used a quantitative structure-activity…

Impact of structural features of odorant molecules on their retention/release behaviours in dairy and pectin gels

International audience; Reducing of fat content in food requires a reformulation that may cause a different perception of aroma. Maintaining an adequate level of acceptability of these reformulated products for consumers requires a better understanding of the mechanisms that control the retention of odorant molecules in food matrices. Although pectins are commonly employed as thickeners, their effect on the retention of odorant molecules in nonhomogeneous products has been examined more frequently than their effect on the retention of odorant molecules in simple gels models.The purpose of this study was to explore and compare the respective effects of pectin in simple model systems. The rel…

The salivary reactor: an innovating tool for the categorization of food products through their aroma and taste compounds release profiles

International audience

The effect of glycerol on the perceived aroma of a model wine and a white wine

Abstract Glycerol is one of the most abundant components of wine. In dry wines its concentration is only exceeded by water and ethanol. Several studies have been carried out on the effects of glycerol on mouthfeel, but little attention has been given to glycero–flavour interactions. Consequently, here we have turned our attention to the aroma perception. Purge and Trap analysis and sensory measurements were used to investigate the modifications in volatility of aroma compounds in model solutions and white wine according to their glycerol concentration. In water, the amount of aroma compounds released was not affected by the presence of glycerol concentrations ranging from 5 to 50 g/L. The a…

Le stress biotique, le décorticage ou la variété influencent la présence d'off-flavors dans la farine de pois

National audience

Release of aroma compounds from fat spread in a salivary reactor

International audience

Flavor release and rheology behavior of straberry fatfree stirred yogurt during storage

International audience

Influence of aroma compounds on the mechanical properties of pectin gels.

A detailed study of the rheological behavior of pectin gels, in the presence of aroma compounds in food concentration is reported. In high methoxylated pectin (HMP) gels, it has not yet been shown if aroma compounds can be responsible for modifications in rheology. Two rheological techniques were used to measure the impact of aroma substances on rheological properties of HMP-based systems. Maximum strain to fracture (sigma F) was compared between flavored and unflavored gels on stress-displacement curve, which was obtained with uniaxial compression until fracture. An oscillatory rheometer was applied to determine the gelation time (Tgel). It appeared that all the aroma compounds studied inc…

Aroma compound sorption by oak wood in a model wine

Oak wood used for wine barrels was immersed into a model wine containing eight aroma compounds (e.g., aromatic and terpene alcohols, ethyl esters, and aldehyde), for which activity coefficients in water and model wine were determined using the mutual solubility measurement. A mass balance of these volatiles considering their reactivity in model wine was established. For most of the studied aroma compounds, and mainly for linalool and ethyl octanoate, a sorption behavior into wood was reported for the first time. This phenomenon was selective and could not be related to the solubilities in model wine and hydrophobicities of the studied aroma compounds, suggesting that acid-base and polar cha…

From sensory evaluation to food product development: how to fit a new vegetal fermented product to the consumer taste

International audience; We present a series of studies showing the role of sensory evaluation in the optimization of new vegetal fermented products.The first series of studies showed that French consumers did not accept fermented products with vegetal protein ratio over 10%.Moreover, positive information on vegetal protein benefits did not lead to an increase in liking scores. So, a second series ofstudies was carried out in order to optimize the raw material and processes used to prepare the products and improve theirorganoleptic properties. In a first step, the vegetal proteins were purified permitting to obtain firmer products with less offflavors. In a second step, the effect of four fa…

Retention/release equilibrium of aroma compounds in fat-free dairy gels

BACKGROUND: The replacement of fat by thickeners in fat-free yoghurts leads to an important modification of aroma compound partitioning, with an impact on aroma perception. Investigation of retention/release equilibria allows a good understanding of aroma compound behaviour depending on food composition. RESULTS: Vapour/liquid equilibria of ten aroma compounds (two esters, two ketones, three aldehydes and three alcohols) in several media were studied to investigate the influence of pectin addition to fat-free dairy gel on the retention/release equilibrium. The partition coefficient of each aroma compound was measured by headspace analysis at equilibrium in six media (pure water, low-methoxy…

Determination of volatiles and sensory profiles in grape juices from Gamay

International audience

MOOC : "ProtéiNNOV : Protéines végétales et Innovation"

La prise de conscience d'une raréfaction des ressources en protéines animales dans les décennies à venir et la nécessité de produire plus durablement ces ressources alimentaires nous conduit à repenser aux autres sources de protéines, notamment les protéines d'origine végétale. Parmi les sources de protéines végétales, la plus employée comme substitut des protéines animales est le soja, mais le soja n'est pas la seule source de protéines végétales. Il est donc opportun de faire le point sur les autres sources de protéines végétales et sur leur utilisation. Le développement de nouveaux produits alimentaires riches en protéines végétales passe par la connaissance des atouts tant technologique…

Effet colloide-protecteur d'extraits de parois de levures sur la stabilité tartrique d'une solution hydro-alcoolique modèle

<p style="text-align: justify;">L'effet colloïde-protecteur d'extraits mannoprotéiques de parois de levures vis-à-vis de la précipitation tartrique a été étudié en solution hydroalcoolique, en utilisant un IST mètre (Indice de Stabilité Tartrique).</p><p style="text-align: justify;">Nous avons montré que les deux extraits levuriens inhibaient la cristallisation du bitartrate de potassium au même titre que l'acide métatartrique et la carboxyméthylcellulose, mais à un niveau plus faible. Le niveau de stabilité retenu (ISTC-75) est assuré avec des concentrations par litre de 7,5 mg d'acide métatartrique et de 18 mg de carboxyméthylcellulose. Des concentrations en extraits man…