In situ targeted activation of an anticancer agent using ultrasound-triggered release of composite droplets

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Étude de l'influence des procédés et de la formulation sur l'arôme du pain (contribution des techniques de piégeage des composés volatils au cours de la cuisson et en conditions de mastication)

Ces travaux ont pour objectif de décrire l impact de la congélation et de la précuisson, ainsi que l impact d ingrédients à bénéfice santé sur le développement de l arôme du pain. Les propriétés physiques et la flaveur globale des produits ont été analysées sensoriellement et instrumentalement. Ce travail a nécessité l optimisation d une technique d extraction des composés volatils permettant d obtenir des extraits représentatifs de l odeur du pain. Deux techniques d extraction en conditions dynamiques ont ensuite été développées: un prototype de bouche artificielle qui reproduit les conditions de mastication en bouche humaine et qui extrait les composés volatils responsables de l arôme du pain, ainsi qu un système assurant le piégéage des composés volatils libérés au cours de la cuisson des pains. Il a été demontré que les étapes de précuisson et de congélation n avaient pas d influence sur la qualité organoleptique des produits pour un même niveau de cuisson. L analyse de différentes formules avec des qualités nutritionnelles améliorées (pain sans gluten, pain enrichi en fibres (inuline), pain complet enrichi en phytase) a mis en évidence l impact de ces formulations sur le profil aromatique du pain. Il a alors été démontré que l ajout d inuline accélère la cuisson des pains. De plus, pour un même niveau de cuisson, l inuline modifie peu la perception des pains, ce qui en fait une perspective intéressante pour améliorer leur qualité nutritionnelle sans modifier leur appréciation par les consommateurs. Par ailleurs, l étude de la cinétique de cuisson de ces pains a permis d identifier des indicateurs physiques de l évolution de la réaction de MaillardThis work aims to describe the impact of freezing and partbaking, as well as the impact of functional ingredients on the development of the aroma of bread. The physical properties and the overall flavor of the products were analyzed sensory and instrumentally. This work required the optimization of an extraction technique of volatile compounds to obtain extracts representative of the smell of bread. Two extraction techniques in dynamic conditions were then developed: an artificial mouth device that mimics the conditions of human mastication and which was able to extract the volatile compounds responsible for the aroma of bread, and a system which permits the trapping of volatile compounds released during the baking of bread. Results demonstrated that the freezing and partbaking stages did not affect the organoleptic quality of products. The analysis of different formulations with improved nutritional qualities (gluten-free bread, bread enriched with fiber (inulin), bread enriched with phytase) highlighted the impact of these formulations on the flavor profile of the bread. It was shown that adding inulin accelerates bread baking. In addition, for the same level of baking, inulin modifies a little the perception of breads, which makes it an attractive prospect to improve their nutritional quality without affecting their appreciation by consumers. Furthermore, the study of the kinetics of the bread baking permitted to identify physical indicators of the evolution of the Maillard reactionNANTES-BU Sciences (441092104) / SudocSudocFranceF

Searching for organic compounds in the Universe

International audienceSearching for signs of past or present life in our Solar System is a major challenge for the space-research community. One approach involves searching for organics. However, it encompasses major challenges, such as their very low concentration levels, their ambiguous origins (biotic or abiotic) and their supposed diversity and complexity. Even if, during the past 40 years, tremendous improvements in sample treatment, stationary phase and mass spectrometry detection have been achieved, there is still a need for new in-situ scientific instrumentation. The objective of this article is to give a broad canvas of instrumentation and technology available to space-survey missions and those further out. It is also a critical review where we discuss analytical science questions, and the technology needed to address the

Chapitre 2 - Development of Artificial Mouths for In Vitro Studies of Aroma from Liquid and Solid Foods

International audienceThis chapter deals with the development of "artificial mouths" in food aroma research. After a brief outline on how aroma is perceived in vivo, the need to develop instrumental techniques that reproduce mouth conditions is explained. The devices described in the literature are then presented, and the difficulties and advances in reproducing oral functions, such as mouth temperature, saliva, breathing and mastication, are discussed. Finally, the artificial mouth designed by the authors is presented as well as the improvements it will bring in food aroma research. In particular, this is the first device enabling the aroma of especially hard food to be studied. By means of this technique, volatile compounds contributing to the aroma perception of all kinds of foodstuffs can be identified and a better understanding of the release of aroma during mastication will be possible

Bouche artificielle simulant la mastication et procédé d’analyse des composés à l’origine de la perception sensorielle, notamment des arômes, mettant en œuvre une telle bouche artificielle

L'invention concerne une bouche artificielle comprenant une enceinte (1) fermée hermétiquement, dans laquelle des aliments (6) sont placés entre deux plateaux (4, 5) animés de mouvements relatifs aptes à déstructurer lesdits aliments en simulant la mastication. Une membrane (19) souple, couplée au mouvement d'un des plateaux mime le gonflement des joues et favorise, en combinaison avec un flux gazeux constant, la libération des composés volatils des aliments, responsables de l'arôme dudit aliment. Cette bouche artificielle, qui simule à la fois la mastication et la respiration humaine, peut être connectée à un cône d'olfaction (24), et/ou un dispositif de piégeage, et/ou un chromatographe permettant d'analyser les composés à l'origine de la perception sensorielle des arômes

Bread aroma

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Validation of trace amount determination of monocyclic and polycyclic aromatic hydrocarbons in several fruits

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Polycyclic aromatic hydrocarbons in fruits and vegetables: Origin, analysis, and occurrence

International audienceFeed intake, for non-smokers, is the first route of contamination to polycyclic aromatic hydrocarbons (PAHs), which are potentially toxic compounds via ingestion. Investigations are focused on the presence of PAHs in fruits and vegetables. Transfer of PAHs can occur from air and soil during cultivation. They can also appear prior to consumption during storage, transport or cooking processes.Rather low amounts of PAHs are usually detected in raw fruits and vegetables. Quantities are between 0.01 and 0.5 μg kg-1 (wet weight) for compounds classified as priority pollutants by the US Environmental Protection Agency (EPA). However, several studies point out that concentrations of some PAHs can exceed 0.5 μg kg-1 wet weight in diverse fruits and vegetables and even reach 5 μg kg-1. Amounts can be very different depending on the surrounding area of the crops, the aromatic hydrocarbon, or even the product itself. PAHs content is usually higher for products grown near roadways or in urban regions than in rural areas. Trace level of compounds such as phenanthrene, fluoranthene and pyrene have been found in quite every raw fruit and vegetable. Relative high amounts of lighter PAHs such as naphthalene, acenaphthylene, and acenaphthene have been found in some of them

Development of extraction and analytical strategies for investigation of aromatic hydrocarbons in apples

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