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International audience; The rapid and preferential adsorption of a gastric lipase recombinant dog gastric lipase (rDGL) in heterogeneous films of phospholipids and triacylglycerols has previously been unveiled using Langmuir films analyzed by tensiometry, ellipsometry and Langmuir-Blodgett transfer coupled to atomic force microscopy. Here we invest the adsorption behavior of rDGL in heterogeneous galactolipid and mixed galactolipid-phospholipid or galactolipid-phospholipid-phytosterol films representative of plant membrane. Again rDGL, preferentially got adsorbed at the expanded lipid phases of the films underlining the genericity of such adsorption behavior. The addition of phytosterols to these mixtures resulted in the creation of defects, favoring the adsorption of rDGL at the fluid phases, but also improving the adsorption capacities of the lipase at the phase boundaries and towards the defects in the condensed phase. rDGL, like all gastric lipases, does not show any activity on galactolipids and phospholipids but its adsorption impacts their lateral organization and may change the adsorption and activity of other lipolytic enzymes in the course of digestion.

The effects of lactic acid fermentation using Lactiplantibacillus plantarum 75 (L75), Leuconostoc pseudomesenteroides 56 (L56) and its combination (L56 + 75) on the quality, bioactive and volatile compounds of mango juices (MJ) from three cultivars (‘Peach’, ‘Sabre’ and ‘Tommy Atkins’) were investigated. Fermented and unfermented MJ were evaluated for LAB growth, physicochemical parameters, volatile compounds, antioxidants activities (DPPH, ABTS, FRAP methods), total phenolic content (TPC) and sensory properties. The unfermented juices served as a control. Twenty-four-hour fermentation was ideal for MJ based on LAB growth profiles. Generally, titratable acidity, TPC, FRAP, DPPH and ABTS scavenging activities significantly increased with fermentation by the L75 strain and were highest in the L75-fermented ‘Sabre’ MJ, while L75-fermented ‘Peach’ MJ had higher ABTS activity (p < 0.05). In contrast, the L56 strain enhanced β-carotene retention, with improved colour properties in L56-fermented ‘Peach’ MJ. Fermentation with L75 in ‘Sabre’ and ‘Peach’ MJ aided the synthesis of new volatile compounds (alcohols, esters, ketones and aldehydes). A PLS-DA scatter plot showed two clusters separating the ‘Peach’ and ‘Sabre’ mango juice fermented with L75 from the rest. Based on the variable importance of the projection value (VIP) scores, pentadecane, 8-hexyl and butyl isobutyrate were shown as marker candidates to distinguish ‘Peach’ and ‘Sabre’ MJ fermented with L75 from the other treatments, whereas ethyl octanoate and isobutyl acetate differentiated the ‘Sabre’ MJ fermented with L75 from the other treatments. ‘Sabre’ and ‘Peach’ MJ fermented with L75 and L56 could provide antioxidants, meeting the recommended daily requirements for ascorbic acid and carotenoids in adults and teenagers. Hence, lactic acid fermentation of these local cultivars is a way to benefit consumers.

International audience; Fresh pineapple juice exhibits a shelflife of a few days limited by the development of yeasts and molds. An approach was implemented to assess the efficacy of treatments of juice, based on three successive steps. The first step was to validate the use of a microbial cocktail which leads to juice spoilage. In a second step, the efficacy of treatments was assessed on the growth of fungi in two conditions. The treatment chosen was the addition of Thymus leptobotrys (Tl) and Thymus maroccanus (Tm) essential oils (EO). These extracts were mainly composed of the monoterpene carvacrol, and inhibited fungal growth in culture medium. The addition of EO to pasteurized juice inoculated with a fungal cocktail limited fungal population below 4.6 log CFU/mL during 14 days. The low pH of pineapple juice probably strengthened the effect of antifungal compounds acting on proton gradient across plasma membrane. Lastly, the efficacy of the treatments was assessed in fresh pineapple juice harboring its natural microbial population. The extracts TlEO at 0.25%o or TmEO at 0.05%o limited fungal growth below 5 log CFU/mL during 14 days. Thyme scent was detected after EO addition but the characteristic descriptors of pineapple and sugary were maintained.

International audience; Dietary diversification, which starts between 4 and 6 months, is a pivotal period in the infant development. After this diversification, complementary foods such as infant flours are therefore widely consumed throughout the world, particularly in southern countries. However, infant flours have often an unbalanced lipid profile in favor of omega 6 and overages in certain vitamins content (especially A and E). The aim of this study was to optimize the formulation of enriched infant flour in order to improve its nutritional profile and oxidative stability. For this purpose, the nutritional values and ingredient lists of 96 infant flours were analyzed to formulate model flours representative of the marketed products. The lipid profile of these model flours was then optimized by including flours with balanced omega 6/omega 3 ratios, i.e. teff and cowpea flours, and/or by adding long-chain polyunsaturated fatty acid (LC-PUFA) powder (DHA and ARA). After 3 months of storage, the optimized flour showed a quite good resistance to oxidation with a low evolution of peroxide values and a low tocopherols degradation. However, the inclusion of LC-PUFA significantly increased the oxidation sensitivity of the flours. In order to counteract this phenomenon, phenolic compounds were added via the addition of brown rice bran which did not seem to have a positive effect on stabilization regardless the particle size. Nevertheless, optimized omega 3 enriched and fortified infant flours could be proposed with fair stability over 3 months of storage.

International audience; Germination is a traditional process and a re-emerging trend in healthy foods, resulting a progressively increase in scientific research on their nutritional traits and phytochemical contents. This review examines the physiological and biochemical changes during the germination sensu stricto in pulses, taking into consideration the genotype, environmental conditions, hormone control, and the metabolic transition from seed to seedling. Germination sensu stricto is achieved as soon as elongation of the radicle, implies heterotrophy metabolism; further thermal processing is needed before consumption. In contrast, seedlings production requires a long period of imbibition and can provide a ready-to-eat food product. Furthermore, proteins, carbohydrates, minerals, vitamins, and antinutritional compounds of pulses are described. Impacts of food processing, such as soaking, germination, and cooking, in nutritional and antinutritional values are also evaluated. The association of soaking, germination, and cooking increases the nutritional values of pulses by increasing protein/starch digestibility and vitamins content and by decreasing antinutritional compounds. The final plant-based product allows versatility in formulation to produce novel food products and/or ingredients with better nutritional content. This can encourage the scientific community, industry, and government to invest in research and development to increase germinated pulse-based food, to replace other products, or to develop new ones.

International audience; Pancreatic lipase related-protein 2 (PLRP2) exhibits remarkable galactolipase and phospholipase A1 activities, which depends greatly on the supramolecular organization of the substrates and the presence of surfactant molecules such as bile salts. It is responsible for the effective hydrolysis of the main lipids composing plant photosynthetic membranes, which represent an excellent source of omega-3 for human nutrition. The objective of the study was to understand the modulation of the adsorption mechanisms and enzymatic activity of Guinea pig PLRP2 (gPLRP2), by the physical environment of the enzyme and physical state of its substrate at the nanoscopic and microscopic scales. Langmuir monolayers were used to reproduce homogeneous and heterogeneous photosynthetic model membranes containing galactolipid, and/or phospholipid, and/or phytosterol, presenting uncharged or charged interfaces. The same lipid mixtures were also used to form micrometric liposomes, and their digestion kinetics by gPLRP2 were investigated in the presence or absence of bile salts (NaTDC) during static in vitro, so called “bulk”, digestion. The enzymatic activity of gPLRP2 onto mixed monolayer of galactolipids and/or phospholipids, and/or phytosterols was characterized with an optimum activity at 15 mN/m, in the absence of bile salts. Additionally, gPLRP2 showed enhanced adsorption onto biomimetic model monolayer containing negatively charged lipids, but the compositional complexity in these systems induced a lag phase before the initiation of lipolysis, and a slowdown in enzymatic activity. In bulk, no enzymatic activity could be demonstrated on GL-based liposomes in the absence of bile salts, probably due to the high lateral pressure of the lipid bilayers. In the presence of NaTDC (4 mM), however, gPLRP2 showed both high galactolipase and moderate phospholipase A1 activities on liposomes, probably due to a decrease in packing and lateral pressure upon NaTDC adsorption, and subsequent disruption of liposomes. The understanding of PLRP2 enzymatic activity at the level of natural plant-based assemblies open the way to new strategies to vectorize bioaccessible omega-3 and rebalance human and animal diets.; La lipase pancréatique apparentée à la protéine 2 (PLRP2) présente des activités galactolipase et phospholipase A1 remarquables, qui dépendent fortement de l'organisation supramoléculaire des substrats et de la présence de molécules tensioactives telles que les sels biliaires. Elle est responsable de l'hydrolyse efficace des principaux lipides composant les membranes photosynthétiques des plantes, qui représentent une excellente source d'oméga-3 pour la nutrition humaine. L'objectif de l'étude était de comprendre la modulation des mécanismes d'adsorption et de l'activité enzymatique de la PLRP2 de cobaye (gPLRP2), par l'environnement physique de l'enzyme et l'état physique de son substrat à l'échelle nanoscopique et microscopique. Des monocouches de Langmuir ont été utilisées pour reproduire des membranes modèles photosynthétiques homogènes et hétérogènes contenant des galactolipides, et/ou des phospholipides, et/ou des phytostérols, présentant des interfaces chargées ou non. Les mêmes mélanges lipidiques ont également été utilisés pour former des liposomes micrométriques, et leur cinétique de digestion par la gPLRP2 a été étudiée en présence ou en absence de sels biliaires (NaTDC) au cours d'une digestion statique in vitro, dite "bulk". L'activité enzymatique de la gPLRP2 sur une monocouche mixte de galactolipides et/ou phospholipides, et/ou phytostérols a été caractérisée avec une activité optimale à 15 mN/m, en l'absence de sels biliaires. De plus, la gPLRP2 a montré une meilleure adsorption sur des monocouches modèles biomimétiques contenant des lipides chargés négativement, mais la complexité de la composition de ces systèmes a induit une phase de latence avant l'initiation de la lipolyse, et un ralentissement de l'activité enzymatique. En bulk, aucune activité enzymatique n'a pu être démontrée sur les liposomes à base de GL en l'absence de sels biliaires, probablement en raison de la pression latérale élevée des bicouches lipidiques. En présence de NaTDC (4 mM), cependant, la gPLRP2 a montré des activités galactolipase élevées et phospholipase A1 modérées sur les liposomes, probablement en raison d'une diminution du packing et de la pression latérale lors de l'adsorption du NaTDC, et de la rupture ultérieure des liposomes. La compréhension de l'activité enzymatique de la PLRP2 au niveau des assemblages naturels à base de plantes ouvre la voie à de nouvelles stratégies pour vectoriser des oméga-3 bioaccessibles et rééquilibrer les régimes alimentaires humains et animaux.

International audience; The microalgae Chlorella vulgaris represent a good model for the study of photosynthetic membranes and are rich in photosynthetic proteins, galactolipids, and pigments (Demarco et al., 2022). These photosynthetic organisms have been consumed in some parts of the world for centuries and their nutritional potential has been highlighted in many reports, explaining a growing interest in their use in new food applications (Torres-Tiji et al., 2020). However, their digestibility by gastrointestinal enzymes has not been extensively studied. So we used the Pancreatic lipase related-protein 2 (PLRP2) to get more information on the digestive mechanisms. Indeed, it has been shown to be responsible for the effective hydrolysis of galactolipids, the main lipids composing plant photosynthetic membranes. Guinea pig pancreatic lipase related-protein 2 (gPLRP2) is a model enzyme close to its human analogue, and that has been extensively studied for its ability to hydrolyze a wide range of acylglycerol substrates, exhibiting remarkable galactolipase and phospholipase A1 activity. In this study, Langmuir model monolayers were used to fellow the interfacial behavior of gPLRP2 at the level of natural plant lipid monolayers from Chlorella microalgae extracts, and to understand the impact of the chemical and physical heterogeneity of natural photosynthetic plant membranes on the enzymatic activity of gPLRP2. We compared also with data obtained on lipid extracts from nuts and almonds for which the composition is mainly composed of phospholipids. The results have shown that the enzymatic activity of gPLRP2 is with an optimum activity obtained at 15 mN/m. Interfacial studies showed enhanced adsorption of gPLRP2 onto natural monolayers containing negatively charged lipids, and that the compositional complexity in these systems induced a lag phase before the initiation of lipolysis, and a slowdown in enzymatic activity.; Les microalgues Chlorella vulgaris représentent un bon modèle pour l'étude des membranes photosynthétiques et sont riches en protéines photosynthétiques, galactolipides et pigments (Demarco et al., 2022). Ces organismes photosynthétiques sont consommés dans certaines régions du monde depuis des siècles et leur potentiel nutritionnel a été mis en évidence dans de nombreux rapports, expliquant un intérêt croissant pour leur utilisation dans de nouvelles applications alimentaires (Torres-Tiji et al., 2020). Cependant, leur digestibilité par les enzymes gastro-intestinales n'a pas été étudiée de manière approfondie. Nous avons donc utilisé la lipase pancréatique apparentée à la protéine de type 2 (PLRP2) pour obtenir plus d'informations sur les mécanismes digestifs. En effet, il a été démontré qu'elle est responsable de l'hydrolyse efficace des galactolipides, les principaux lipides composant les membranes photosynthétiques des plantes. La lipase pancréatique de cochon d'Inde (gPLRP2) est une enzyme modèle proche de son analogue humain, et qui a été largement étudiée pour sa capacité à hydrolyser une large gamme de substrats d'acylglycérol, présentant une remarquable activité galactolipase et phospholipase A1. Dans cette étude, des monocouches modèles de Langmuir ont été utilisées pour étudier le comportement interfacial de la gPLRP2 au niveau de monocouches lipidiques végétales naturelles provenant d'extraits de microalgues Chlorella, et pour comprendre l'impact de l'hétérogénéité chimique et physique des membranes végétales photosynthétiques naturelles sur l'activité enzymatique de la gPLRP2. Nous avons également comparé avec les données obtenues sur des extraits lipidiques de noix et d'amandes dont la composition est principalement composée de phospholipides. Les résultats ont montré que la gPLRP2 présente une activité optimale à 15 mN/m. Les études interfaciales ont montré une adsorption accrue de la gPLRP2 sur des monocouches naturelles contenant des lipides chargés négativement, mais également que la complexité de la composition de ces systèmes induisait une phase de latence avant l'initiation de la lipolyse, et un ralentissement de l'activité enzymatique.

International audience; Infancy period is a key window of development during which the requirements in lipids and more particularly in long-chain polyunsaturated fatty acids are specific. In order to abide by the recommendations, European regulation now requires a fortification of infant follow-on formulas (IFF) with docosahexaenoic acid (C22:6, DHA) which strongly impacts their oxidative stability. The aim of this study was to optimize the structure and formulation of DHA-enriched IFF in order to improve their lipid profile and oxidative stability. To do so, a model IFF representative of marketed products was formulated and declined by varying the saturated fatty acids sources (refined (POM) or unrefined (RPOM) palm oil, coconut oil (COM), and dairy fat (DFOM)), the emulsifiers (soy lecithin or dairy phospholipids (DPL)) and the structure (droplet size). These model IFF were submitted to an accelerated storage test of 20 days at 40°C during which peroxide values (PV), tocopherols, vitamin A, and fatty acids profiles were monitored. Despite the addition of DHA, all model IFF had quite good oxidative stability with PV lower than 10 meqO2/kg of lipids until 9 days of storage. DFOM and POM had equivalent kinetics of PV increase and tocopherols degradation. Moreover, no significant differences were observed between these two IFF regardless of droplet size (0.4 or 0.7 µm). RPOM was more stable than POM, very likely due to its higher carotenoids content. Regarding emulsifiers, DFOM-DPL (stabilized with DPL) had a PV twice lower than POM (stabilized with lecithin) at 20 days and a tocopherols degradation of 67.5% vs 88.8% for POM. This result translates a more important resistance to oxidative degradation of DFOM-DPL. This favorable effect was even reinforced for smaller droplet sizes. The introduction of dairy lipids but also of carotenoids in DHA-enriched IFF composition are interesting levers of stabilization. Moreover, dairy lipids lead to a more complex lipid profile and a higher content of short and medium-chain saturated fatty acids which is beneficial for infant nutrition.

International audience; Pancreatic lipase related-protein 2 (PLRP2) exhibits remarkable galactolipase and phospholipase A1 activities, which depend greatly on the supramolecular organization of the substrates and the presence of surfactant molecules such as bile salts. The objective of the study was to understand the modulation of the adsorption mechanisms and enzymatic activity of Guinea pig PLRP2 (gPLRP2), by the physical environment of the enzyme and the physical state of its substrate. Langmuir monolayers were used to reproduce homogeneous and heterogeneous photosynthetic model membranes containing galactolipids (GL), and/or phospholipids (PL), and/or phytosterols (pS), presenting uncharged or charged interfaces. The same lipid mixtures were also used to form micrometric liposomes, and their gPLRP2 catalyzed digestion kinetics were investigated in presence or in absence of bile salts (NaTDC) during static in vitro, so called “bulk”, digestion.The enzymatic activity of gPLRP2 onto the galactolipid-based monolayers was characterized with an optimum activity at 15 mN/m, in the absence of bile salts. gPLRP2 showed enhanced adsorption onto biomimetic model monolayer containing negatively charged lipids. However, the compositional complexity in the heterogeneous uncharged model systems induced a lag phase before the initiation of lipolysis. In bulk, no enzymatic activity could be demonstrated on GL-based liposomes in the absence of bile salts, probably due to the high lateral pressure of the lipid bilayers. In the presence of NaTDC (4 mM), however, gPLRP2 showed both high galactolipase and moderate phospholipase A1 activities on liposomes, probably due to a decrease in packing and lateral pressure upon NaTDC adsorption, and subsequent disruption of liposomes.

The purpose of the study is to characterize the chemical diversity in Rice bran (RB) lipidome and determine whether daily RB consumption for 4 weeks may modulate plasma lipid profiles in children.Untargeted and targeted lipidomics via ultra-performance liquid chromatography coupled with high-resolution tandem mass spectrometry (UPLC-MS/MS) were applied to identify bioactive RB lipids from a collection of 17 rice varieties. To determine the impact of RB (Calrose-USA variety) supplementation on plasma lipid profile, a secondary analysis of plasma lipidome was conducted on data recorded in a clinical study (NCT01911390, n = 18 moderately hypercholesterolemic children) before and after 4 weeks of dietary intervention (15 g/d) with a control or RB supplemented snack. Untargeted lipidomic revealed 118 lipids as the core of lipidome across all 17 varieties among which phospholipids were abundant and oxylipins present. Phytoprostanes and phytofurans were quantified and characterized. Lipidome analysis of the children plasma following RB consumption revealed the presence of novel polar lipids and oxylipins alongside putative modulations in endocannabinoids associated with RB consumption.The investigation of novel polar lipids, oxylipins, phytoprostanes, and phytofurans in RB extracts provides support for new health-promoting properties especially interesting for people at risk for cardiometabolic disease. This article is protected by copyright. All rights reserved.

National audience; La période postnatale est caractérisée par une croissance et un développement rapide. Les lipides et plus particulièrement les acides gras polyinsaturés à longues chaînes (AGPI-LC) tels que les acides docosahexaénoïque (DHA) et arachidonique (ARA) jouent un rôle essentiel durant cette période. L’objectif principal des formules infantiles est d’être biomimétique de « l’étalon d’or » : le lait maternel, aussi bien en termes de composition que de structure, pour ainsi offrir la meilleure alternative possible à l’allaitement lorsqu’il a échoué et/ou n’est pas possible. Dans ce contexte, la réglementation européenne a évolué pour encourager une optimisation de la composition des préparations infantiles. Ainsi, depuis février 2020 la supplémentation des formules en DHA a été rendue obligatoire. Ces formules sont également fortifiées en ARA, autre AGPI indispensable pour le développement de l’enfant, bien qu’aucune obligation ne soit établie quant à sa teneur minimale. Leur important degré d’insaturation rend ces acides gras particulièrement sensibles à l'oxydation lipidique, complexifiant ainsi leur introduction dans les formules infantiles. Les lipides laitiers du fait de leur haute teneur en certains acides gras saturés constituent donc un atout pour la stabilisation contre l’oxydation. De plus, d’un point de vue structurel, des différences persistent entre le lait maternel et les formules infantiles ce qui a un fort impact sur les cinétiques de digestion et donc d’absorption des nutriments. Une fois de plus, les lipides laitiers (polaires ou apolaires) du fait de leur structure et composition complexe, présentent un intérêt particulier pour le développement de l’enfant notamment en modulant la digestion des protéines, le développement intestinal et en contribuant à l’éducation immunitaire et à celle du microbiote. L’objectif de cet exposé est de mettre en évidence, à travers une étude de stockage, l’intérêt technologique et nutritionnel de la réintroduction des lipides laitiers dans la composition des préparations de suite afin de les stabiliser contre l’oxydation.

International audience; Long-life cycle pulses have significant food security potential, however, there is little evidence to explain why they are not more widely produced and consumed in sub-Saharan Africa (SSA). This study aimed at exploring existing knowledge to inform on future research priorities in mainstreaming superior species. As staple food along with cereals, pulses are an important source of nutrients whose intake is often inadequate in SSA, however, pulse consumption remain inadequate in SSA. Depending on the crop's life cycle, pulses have multiple functions that can support food systems and ecosystem resilience. Compared to short-life cycle pulses, long-life cycle pulses rank higher in multipurpose role. However, prior research has focused primarily on short-life cycle pulses due to rapid grain production. Long-life cycle pulses remain underutilized and neglected despite showing steady but modest yield increases and adaptation to environments, suggesting that they are better positioned to respond to the diverse needs of smallholder farmers in SSA. In the context of climate change, rain-fed agriculture, depleted agricultural soils, and lack of subsidized fertilizers, there is need to transform existing food systems toward sustainable food production and improved resilience. Increasing pulse agrobiodiversity by integrating long-life cycle pulses in existing farming systems could not only contribute in alleviating malnutrition, but also poverty and inequalities. In addition, representative and accurate data are needed based on the correct use of accepted scientific names for all data across the food system. This is a prerequisite for assessing pulse consumption adequacy and quantifying production and consumption trends.

National audience; The lipid fraction of infant follow-on formulas is mainly composed by a mixture of oils mainly of vegetable origin with palm oil as the main source of saturated fatty acids and are enriched in long-chain polyunsaturated fatty acids to support the infant development. However, these oil blends are not optimal for nutritional needs of infants and are particularly sensitive to lipid oxidation. This study aimed to substitute palm oil with other sources of saturated fatty acids in order to ensure a more suitable nutritional profile for infant without impacting or improving stability against lipid oxidation. A panel of model IFF representative of marketed products was formulated depending on the lipid sources including refined or unrefined palm oil, coconut oil and dairy fat. After an accelerated storage to follow their oxidative stability, the results show that the inclusion of carotenoids and dairy lipids in the composition of the oil phase improved the stability against lipid oxidation and provides bioactive compounds that are involve in the infant development. This study has thus highlighted the importance of the balance between nutritional profile and oxidation stability.

International audience; Langmuir films and their analysis by tensiometry, ellipsometry and Langmuir-Blodgett transfer coupled to atomic force microscopy are suitable tools to study the interactions of various lipases with model membranes. The objective of our study was to characterize the adsorption and lipolysis behavior of different gastrointestinal enzymes onto biomimetic vegetal membranes. An heterogenous monolayer based on a mixture of unsaturated galactolipids (MGDG, DGDG), saturated phospholipids (DPPC), and phytosterols was used. Four enzymes were studied, i) gastric lipase (GL), which has no lipolytic activity on polar lipids but whose adsorption may modulate the subsequent adsorption and activity of other lipases, and three pancreatic enzymes: ii) pancreatic lipase 2 (PLRP2) presenting both galactolipase and phospholipase A1 activities, (iii) pancreatic triacylglycerol lipase and its cofactor, colipase (PTL/coPTL), and (iv) pancreatic secreted phospholipase A2 (sPLA2-IB). A strong surfactant property of GL and its preferential adsorption at both the expanded lipid phase and at the boundary phase were observed, in line with previous results obtained with biomimetic milk fat globule membrane. With PLRP2, changes in surface pressure indicated a lipolytic activity in addition to lipase adsorption, with a higher rate at surface pressure below 15 mN/m. A drastic decrease in film thickness was also observed by ellipsometry, suggesting the removal of some lipolysis products. Such variation was not observed upon PTL/coPTL adsorption, and may be related to the absence of activity of PTL on polar lipids. Finally, the evolution of adsorption kinetic after injection of sPLA2-IB did not indicate a clear trend of lipolysis on the lipid film. However, a change in the morphology of condensed domains was observed by AFM, suggesting a phase separation of lipids induced by binding of sPLA2-IB.This study is a step forward in the understanding of interaction of gastrointestinal lipases with plant lipid membranes, an overlooked aspect of lipid digestion.

International audience; The structural behavior of model assemblies composed of monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG), the two main galactolipids found in plants, was investigated at the air/water interface and in aqueous dispersion. To approach the composition of the natural photosynthetic membranes, tunable Langmuir model membrane of galactolipids (GL) were used, and were complexified to form either heterogenous binary or ternary assemblies of GL, phospholipids (PL), and phytosterols (pS).The impact of pS, 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) or both on the structural properties of GL membrane was studied. The nature of the interactions between the different molecules was investigated using biophysical characterizations (ellipsometry, tensiometry, atomic force microscopy). In addition, the phase behavior was determined by SAXS analysis on the model assemblies in aqueous dispersions.Results revealed the good interfacial stability of these specific plant membrane lipids. The morphology of the GL film was characteristic of a fluid phase, with an interfacial roughness induced by the intercalation of monogalactosyl and digalactosyl polar heads of MGDG and DGDG, respectively. A phase heterogeneity in the monolayer was induced by the addition of DPPC and/or pS, which resulted in the modification of galactolipid organization and headgroup interactions. These structural changes were confirmed by SAXS analysis, showing more favorable interactions between MGDG and DPPC than between DGDG and DPPC in aqueous dispersion. This phenomenon was exacerbated in the presence of pS.HIGHLIGHTS • Plant polar lipids formed stable monolayers at the air/water interface. • Phytosterols reduced the lateral elasticity of galactolipid and DPPC monolayer. • DPPC has affected MGDG-DGDG interactions. • Results highlighted preferential phase miscibility between DPPC and MGDG.

Citrus juices can be cold-concentrated by crossflow microfiltration (CMF) in order to obtain functional foods enriched in carotenoids, flavonoids and pectins. The work aimed to characterize the organoleptic quality of this type of micronutrient-dense foods through their aroma profile and sensory analysis. Two citrus concentrates with and without a diafiltration step were compared.Both citrus products were very different, linked to aroma compound, sugar and organic acid contents. Due to its sugar/acidity balance and its better aromatic profile responsible for the citrus-floral flavour, the concentrate without diafiltration was preferred by the sensory panel. Thanks to a simple transfer model, we showed that retention of volatiles clearly varied from one aroma compound to another. The terpene hydrocarbons were the most retained by the membrane during CMF, probably because they were strongly associated with insoluble solids by adsorption.Even though the process modified their organoleptic profiles, both citrus-based products were well rated and can be consumed directly as pleasant functional drinks. © 2022 Society of Chemical Industry.

International audience; Fresh carrot juice presents nutritional and organoleptic qualities which have to be preserved. However, it is a fast perishable beverage, and its low-acidic pH promotes the development of foodborne pathogens and spoilage microorganisms. This study aims to assess the modification and variability of physicochemical and microbial indicators during storage of carrot juice, and to isolate and select microorganisms to be used as promoters of spoilage to quantify the effect of preservation treatments. To achieve that, 10 batches of carrot Daucus carota cv. Maestro juice were prepared independently, stored up to 14 days at 4 °C and analyzed. Volatile compound composition differed mainly according to the analyzed batch. During storage, an increase of the content of ethanol, ethyl acetate or 2-methoxyphenol, which are produced by different microorganisms, was noticed. Isolation of bacteria revealed Pseudomonas, lactic acid bacteria, and enterobacteria, some of them provoking odor modification of carrot juice at 4 °C. Assays in carrot juice with isolated yeasts and molds showed the ability of Meyerozyma guillermondii to induce texture modification and some isolates, e.g., Pichia guillermondii, resulted in gas production. Selected isolates able to induce spoilage are useful to test preservative treatments of fresh carrot juice under controlled conditions.

3rd International Symposium on Nutrition (ISN 2022): Urban Food Policies for Sustainable Nutrition and Health, 27–28 January 2022; International audience

International audience; The residual biomass of cold-pressed green coffee oil (GCO), rich in chlorogenic acids (CGA), was reused by incorporating the press cake (CE) and sediment (SE) extracts into carboxymethyl cellulose (CMC) films. The effect of these extracts combined with GCO was investigated on the physicochemical, barrier, and antioxidant properties, and on the ability of the active films to delay fish oil oxidation. The films with added CE and GCO (C-CE) or SE and GCO (C-SE) showed high antioxidant activity, 3.61 ± 0.01 and 2.03 ± 0.01 mmol Trolox eq/g dry film, respectively. These findings are in line with the CGA content in CE and SE (9.8 and 9.0% w/w, respectively), as determined by HPLC. The addition of SE and GCO slightly affects the oxygen barrier of CMC films, while providing them with high Ultraviolet–Visible (UV–Vis) absorption. The evolution of peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) in fish oil samples covered by C-CE and C-SE films and inert headspace was significantly lower than those of controls (storage at 40 °C for 16 days). The antioxidant release from films with added CE and SE showed an antagonistic behaviour into the food simulants. Although both active films are promising for active packaging, the C-SE film appeared as more advantageous for oil-rich food protection.

International audience; Bananas are tropical fruits that are perishable and susceptible to fungal diseases, mainly caused by Colletotrichum musae. Antimicrobial emulsion-based coating materials have been used extensively to inhibit the growth of these fungi and extend the shelf life of bananas. Targeted emulsion-based film functionalities offer excellent mechanical, physicochemical and barrier properties and limit fungal growth kinetics. Antifungal compounds, such as essential oils or phenolic compounds, are added to emulsion-based (wax/ biopolymer) coatings to enhance their antimicrobial properties. This study set out to formulate a beeswax-based emulsion for banana coatings using high-pressure homogenisation (HPH) and hydrophilic food-grade/organic coating materials. The particle size distribution, stability and mechanical properties of the film-forming emulsions, water vapour and the oxygen permeabilities of the resulting coating were investigated. The most promising sucrose emulsions were tested as coatings on banana fruits to assess their efficacy against moisture and firmness loss during storage. Adding thymol (0.5% w/w) to the sucrose emulsions further enhanced the inhibition of Colletotrichum musae growth to its barest minimum of

International audience; Severe Acute Malnutrition (SAM) is still a public health issue in many low-income and middle-income countries. Its management has changed with the development of Ready-to-Use Therapeutic Foods (RUTF) that are energy-dense, lipid-based, micronutrient-enriched foods. The purpose of the present study was to define some aspects of the nutritional profile (in particular, lipid content, fatty acids profile, lipophilic vitamin content), oxidative status, and mycotoxin content of three RUTF products (of which two manufactured in Asia and one in Europe), at different time points during their storage. All RUTF displayed good lipid stability, with peroxide values

International audience; A fast and low-cost analytical method to determine the concentrations of carotenoids (β-carotene, lutein, and lycopene) from mixed standard solutions or from fruit extracts (kiwi fruits, tomato paste, pink grapefruit juice, kiwi-pineapple smoothie, and apricot nectar) was tested. The methodology was based on UV-Vis spectrophotometry and Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS). Results showed that relative concentrations of β-carotene, lutein, and lycopene in solvent were successfully determined by this technique with an error inferior to 6%. In real extracts, the procedure succeeded well in identifying the major carotenoid type of the fruit samples but also a more complex profile of a fruit mixture. The results also showed that accuracy of carotenoids determination by UV-Vis spectrophotometry-MCR-ALS in fruit extracts was conditioned by their spectral characteristics (III/II ratios and λmax), their relative proportion, and the extract purity.

International audience

International audience; Gastrointestinal lipases are crucial for lipid hydrolysis and must get adsorbed onto the substrate interface prior lipolysis. Such adsorption had not been deeply investigated on biomimetic vegetal membranes. Our objective was thus to characterize such adsorption and lipolysis using complementary biophysical tools (tensiometry, ellipsometry, atomic force microscopy) and in vitro digestion.Heterogenous monolayers based on galactolipids, phospholipids, and phytosterols were used. Four lipases were studied: i) gastric lipase (GL), ii) pancreatic lipase 2 (PLRP2), (iii) pancreatic triacylglycerol lipase and its cofactor, colipase (PTL/coPTL), and (iv) pancreatic secreted phospholipase A2 (sPLA2-IB).A strong surfactant property of GL and its preferential adsorption onto expanded lipid phase and at the phase boundary were observed, in line with previous results on milk fat globule membrane. With PLRP2, changes in surface pressure indicated a lipolytic activity. Such variation was not observed upon PTL/coPTL adsorption, and may be related to the absence of activity of PTL on polar lipids. The injection of sPLA2-IB did not indicate a clear trend of lipolysis on the lipid film but changed the morphology of condensed domains.This study is a step forward to understand the interactions of gastrointestinal lipases with plant lipid membranes, an overlooked aspect of lipid digestion

International audience; This review paper gives an insight into the effective delivery mechanisms for health-promoting substances and highlights the challenges of using antioxidants and bioactives in foods. The selection criteria for choosing bioactives and their extraction in bioavailable form with their adequate incorporation techniques and delivery mechanisms are covered. Moreover, an overview of existing methods for determination of bioactivity is given. The importance of scientifically evaluating the effects of foods or food components on consumer health before making claims about the healthiness is aligned. Finally, a scientific perspective on how to respond to the booming demand for health-promoting products is given, and we acknowledge that despite the work done, there are still many challenges that need to be overcome.

The aim of the study was to evaluate the degradation kinetics of carotenoids (CTs) in vacuum-fried papaya (Carica papaya L.) chips (PCs) during storage at four temperatures (15, 25, 35 and 45 °C) for 52 and 94 days for the two highest and lowest temperatures, respectively. Three treatments were applied to obtain the chips: chips with soy oil (24% lipids) and chips with palm oil (24% and 29% lipids). All the chips were packaged under air or nitrogen conditions. The CTs analyzed by HPLC-DAD were per order of content all-E-lycopene (LYC), Z-lycopene (Z-LYC), all-E-β-carotene (BC), all-E-β-cryptoxanthin (BCX) and Z-β-carotene (Z-BC). The all-E-forms represented 80% of carotenoids in PCs. No significant carotenoid degradation was observed in the PCs packaged under nitrogen conditions during storage. For chips stored under air conditions, a second-order kinetic model best fitted the experimental data. Rate constants for LYC degradation were the lowest, while BCX and BC presented similar rate constants 4–23-fold higher depending on lipid composition. All Z-isomers degraded faster than all-E-forms, but Z-BC degraded only 2–4-fold faster than Z-LYC. All CTs followed Arrhenius temperature-dependency pattern and LYC showed the lowest activation energies (5–21 kJ/mol). A higher lipid content in the chips with palm oil enhanced the carotenoid retention in PCs. Moreover, a greater retention (p

International audience; Aims: This study aimed to determine influence of post-harvest treatments on PAH's formation in raw cocoa.Study Design: A total of 370 samples were analyzed during 2014 and 2015 cocoa harvesting.Methodology: A method based on a solid-liquid and liquid-liquid extraction followed by an HPLC-Fluorescence assay was optimized and validated for PAHs analysis in cocoa.Results: Whatever the post-harvest treatment, cocoa PAH's contents were under 6.19 ± 0.30 µg.kg-1. Then, after traditional warehouse storage of raw cocoa, PAHs contents ranged from 35.11 ± 3.30 to 39.53 ± 0.75 µg.kg-1 above EU standards. Artisanal smoked dried cocoa recorded the highest PAH contents comprising between 35.06 ± 0.42 and 172.22 ± 14.79 µg.kg-1. Also, monitoring of PAH concentrations during make process of cocoa into derived products has shown that shelling reduces the initial contamination of cocoa beans by more than 90%.Conclusion: The use of artificial drying methods and storage conditions in the presence of smoke-induced and increasing PAHs to a critical level. Particularly, drying techniques using smoke caused considerable accumulation of PAHs in raw cocoa.

Oleoproteaginous and cereal seeds enclose a wide range of nutriments such as lipids, proteins, polysaccharides and various mineral and organic micronutrients. These nutrients are found under the form of natural assemblies such as oil or protein bodies or starch granules, that have interesting functionalities (micronic sizes, surface activity, high physicochemical stability, etc.). These assemblies are extracted by various processes using energy, organic solvents, steam, JOURNAL OF THE AMERICAN OIL CHEMISTS' SOCIETY 75 15589331, 2022, S1, Downloaded from https://aocs.onlinelibrary.wiley.com/doi/10.1002/aocs.12654 by CIRAD - DGDRS - DIST, Wiley Online Library on [01/06/2023]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License alone or in combination. Thus, their natural structures are often strongly damaged, and some of their functionalities disappear. Storming through natural assemblies' biodiversity to address the societal demand for more natural and minimally processed food seems promising. Indeed, the soft extraction of such assemblies could be an alternative to traditional intensive fractionation methods of plant raw materials to isolate target ingredients (sucrose, starch, refined oils, etc.). This would allow energy savings and avoid solvent use but must be balanced with potential challenges of this new green refinery scheme. The purpose of the present work is to highlight the physicochemical properties of various oil bodies from diverse plant origins. A green refinery protocol is proposed for their extraction from various matrices. Then their size distribution, surface activity, resistance to oxidation and fatty acids and lipo- soluble vitamins bioaccessibility is also presented. Omega-3 rich sources (linseed, chia, hemp…) are of special interest to correct the low dietary intake of US and European population as well as the ω6/ω3 balance. Oil bodies from these plant species can thus constitute new dietary carriers of ω3 and other bioactive molecules. Moreover, the combination of oil bodies with specific features (fatty acid profiles, stabilities, vitamin contents) can help meeting the requirements of specific nutritional targets (infants, children, elderly, athletes, etc.). Altogether, we are convinced that the valorization of these diverse oil bodies can be a strategic route in the development of sustainable food systems. (Texte intégral)