Search results for "Food and Nutrition"
showing 10 items of 2749 documents
Apprehending ganglioside diversity: a comprehensive methodological approach
2015
Gangliosides make a wide family of glycosphingolipids ubiquitously expressed in mammalian tissues and particularly abundant in the brain and nervous system. They exhibit a huge diversity due to structural variations in both their oligosaccharidic chain and ceramide moiety, which represent a real analytical challenge. Since their discovery in the 1940s, methods have persistently improved until the emergence of Liquid Chromatography/Mass Spectrometry (LC/MS) which offers a high level of specificity and sensitivity and is suitable with high-throughput profiling studies. We describe here a comprehensive approach relying on various techniques and aiming at fully characterizing gangliosides in bi…
L'agriculture urbaine : une agriculture juridiquement comme les autres?
2019
International audience; En plein essor, l'agriculture urbaine se présente comme un défi pour le droit agricole, construit sur un paradigme géographique et sociologique : la ruralité. Dès lors, comment saisir juridiquement ces nouveaux projets productifs, aux formes variées et aux modèles économiques souvent hybrides ? Est-ce aux acteurs urbains de s'adapter à des règles venues d'ailleurs, ou au droit de se tordre pour accompagner le mouvement d'une agriculture des villes, qui questionne celle des champs ?
Study of the biochemical composition and physico-chemistry of a protein-based food model of Parkia biglobosa
2022
In West Africa, the seed of the cowpea (Parkia biglobosa) is used in traditional pharmacopoeia and especially in human food as a condiment. This legume is very rich in proteins and lipids and remains a poorly exploited source of protein. Our thesis focuses on the valorization of Néré seeds for the development of new protein-rich products of plant origin as an alternative to the use of soybean as a basic ingredient. The objectives were : (i)biochemical and physicochemical characterization of protein isolates from Néré seed flour according to the extraction process, (ii) selection of proteolytic lactic acid bacteria capable of fermenting Néré juice, reducing anti-nutritional factors in order …
Retention of aroma compounds in starch matrices: competitions between aroma compounds toward amylose and amylopectin
2002
International audience; The retention of three aroma compounds-isoamyl acetate, ethyl hexanoate, and linalool--from starch-containing model food matrices was measured by headspace analysis, under equilibrium conditions. We studied systems containing standard or waxy corn starch with one or two aroma compounds. The three studied aroma compounds interact differently: ethyl hexanoate and linalool form complexes with amylose, and isoamyl acetate cannot. However, in systems containing one aroma compound, we observed with both starches a significant retention of the three molecules. These results indicate that amylopectin could play a role in the retention of aroma. In systems containing two arom…
Understanding retention and metabolization of aroma compounds using an in vitro model of oral mucosa.
2020
International audience; The mechanism leading to aroma persistence during eating is not fully described. This study aims at better understanding the role of the oral mucosa in this phenomenon. Release of 14 volatile compounds from different chemical classes was studied after exposure to in vitro models of oral mucosa, at equilibrium by Gas-Chromatography-Flame Ionization Detection (GC-FID) and in dynamic conditions by Proton Transfer Reaction- Mass Spectrometry (PTR-MS). Measurements at equilibrium showed that mucosal hydration reduced the release of only two compounds, pentan-2-one and linalool (p < 0.05), and suggested that cells could metabolize aroma compounds from different chemical fa…
Characterization of aged champagne wine aroma by GC-O and descriptive profile analyses
2000
Le but du travail est de caracteriser l'evolution de l'arome du champagne au cours du vieillissement et de comparer sous ce rapport le vieillissement accelere a 40 °C au vieillissement normal. Les methodes mises en oeuvre a cet effet sont l'analyse sensorielle, et les techniques GC-O et GC-MS. La representativite des extraits a ete etudiee au prealable par tests triangulaires et tests de similarite. Les profils descriptifs ont ete etablis par un panel d'experts sur des echantillons jeunes et vieillis. L'intensite des notes florale et fruitee diminue au cours du vieillissement, celles des notes boisee et d'evolution augmentent. On observe cependant des differences sensorielles entre les prod…
Ultrasound-assisted green solvent extraction of high-added value compounds from microalgae Nannochloropsis spp.
2015
Abstract The aim of this work was to investigate ultrasound (US)-assisted green solvent extraction of valuable compounds from the microalgae Nannochloropsis spp. Individual green solvents (water, ethanol (EtOH), dimethyl sulfoxide (DMSO)) and binary mixture of solvents (water-DMSO and water-EtOH) were used for the extraction procedures. Maximum total phenolic compounds yield ( Y p ≈ 0.33) was obtained after US pre-treatment ( W = 400 W, 15 min), being almost 5-folds higher compared to that found for the untreated samples and aqueous extraction ( Y p ≈ 0.06). The highest yield of total chlorophylls ( Y c ≈ 0.043) was obtained after US ( W = 400 W, 7.5 min), being more than 9-folds highe…
Comment favoriser des choix de goûters favorables à la santé au sein du binôme mère-enfant ? : effet d’une intervention « nutritionnelle » ou d’une i…
2020
In France, the midafternoon snack is a frequent habit among children usually characterized by the consumption of fatty, sweet and high-energy-dense foods. If eating behaviours remain flexible and can evolve throughout the life, they are already strongly established during childhood. In this context, improve food habits in terms of midafternoon snack seem important. The thesis aim was therefore to assess the effectiveness of levers aimed at promoting healthy snack choices within mother-child dyads. A first experiment was conducted in order to assess the impact of a nutritional labelling system, the Nutri-Score, on the nutritional quality and on the liking of the snacks chosen within mother-c…
Perception of non-processed semi-hard cheese aroma
2012
Perception of the aroma of food products depends on several factors, involving both the. chemical composition of food and human neurophysiology. The perception of food flavour,. including cheese often relies on the perception of several aroma compounds in mixture in. balanced proportions. The existence of perceptual interactions among aroma compounds in. mixtures and also the release of aroma compounds from the food product are the main factors. that influence the global perceived aroma of food. Hence, the objective of this PhD study was. to investigate the mixture of aroma compounds representing the aroma of semi-hard cheese by. taking into account perceptual interactions among odorants an…
Traditional and new analytical methodology
2010
International audience