Search results for "composition"
showing 10 items of 2675 documents
Développement des préférences sensorielles et du comportement alimentaire dans l'enfance
2013
Mémoire en vue de l’obtention de l’Habilitation à Diriger des Recherches confidentiel
Extraction of essential oil from Aloysia citriodora Palau leaves using continuous and pulsed ultrasound: Kinetics, antioxidant activity and antimicro…
2018
International audience; The impact of continuous and pulsed ultrasound pre-treatments (15, 30 and 45 min) followed by conventional hydrodistillation on the characteristics of extracted essential oils (EOs) from dried leaves of Aloysia citriodora Palau was evaluated for the first time. Chemical composition of EOs, antibacterial and antioxidant activities, as well as the contents in heavy metals (iron, copper, lead, arsenic, and cadmium) were determined. Pretreating the leaves with ultrasound (continuous and pulsed), before hydrodistillation, resulted in shorter extraction time (93.81–121.16 min) and higher extraction yields (2.8 (v/w) %) (p < 0.05), compared to the non-sonicated leaves (extr…
Effect of extrusion on the anti-nutritional factors of food products: An overview
2017
International audience; Edible plant seeds such as cereals, legumes and nuts contain substantial amounts of nutrients including proteins, carbohydrates, minerals, vitamins, and dietary fibers. However, the bioavailability of these nutrients in humans or animals is relatively low, particularly when they are consumed in their unprocessed or raw form. One of the major factors that contribute to a lower nutritional value of legumes and cereals is the presence of naturally-occurring anti-nutritional factors (ANFs, e.g. phytate, tannins and enzyme inhibitors) that indirectly decreasing the bioavailability status of minerals. Fortunately, these ANFs can be modified or reduced through different pro…
Typology of exogenous organic matters based on chemical and biochemical composition to predict potential nitrogen mineralization
2010
Our aim was to develop a typology predicting potential N availability of exogenous organic matters (EOMs) in soil based on their chemical characteristics. A database of 273 EOMs was constructed including analytical data of biochemical fractionation, organic C and N, and results of N mineralization during incubation of soil–EOM mixtures in controlled conditions. Multiple factor analysis and hierarchical classification were performed to gather EOMs with similar composition and N mineralization behavior. A typology was then defined using composition criteria to predict potential N mineralization. Six classes of EOM potential N mineralization in soil were defined, from high potential N minerali…
: J. Sci. Food Agric.
2017
Background: The measurement of carbon isotopic discrimination in grape sugars at harvest (δ13 C) is an integrated assessment of water status during ripening. It is an efficient alternative to assess variability in the field and discriminate between management zones in precision viticulture, but further work is needed to completely understand the signal.; Results: This work, spanning over 3 years, performed in a hillslope toposequence in Burgundy, delineates the relationships between main soil properties (gravel amount, slope, texture) and the grapevine water status assessed by δ13 C. The highest δ13 C, indicating most severe water deficit, was recorded in gravelly soils on steep slopes. The…
Etudes d'objets combinatoires : applications à la bio-informatique
2011
This thesis considers classes of combinatorial objects that model data in bioinformatics. We have studied two methods of mutation of genes within the genome : duplication and inversion. At first,we study the problem of the whole mirror duplication-random lossmodel in terms of pattern avoiding permutations. We prove that the class of permutations obtained with this method after p duplications from the identity is the class of permutations avoiding alternating permutations of length 2p + 1.We also enumerate the number of duplications that are necessary and sufficient to obtain any permutation of length n from the identity. We also suggest two efficient algorithms to reconstruct two different …
Aroma release and chewing activity during eating different model cheeses
2007
International audience; This study focused on the effect cheese properties had on chewing behaviour and aroma release as well as the relationship between them. Chewing activity and the kinetics of aroma release were simultaneously monitored during the consumption of eight model cheeses with the same flavour content. Differences in chewing behaviour explained most of the variability in aroma release among subjects. Aroma release increased with chewing work, bursts’ number and amplitude. For cheese samples, the chewing behaviour varied according to texture. Interaction between cheese composition and the chewing behaviour effects affected aroma release: (i) decreasing fat content increased aro…
Effect of growing area on tocopherols, carotenoids and fatty acid composition ofPistacia lentiscusedible oil
2014
International audience; In this investigation, we aim to study, for the first time, the effect of the growing area on tocopherols, carotenoids and fatty acid content of Pistacia lentiscus fixed oil. Fruits were harvested from eight different sites located in the north and the centre of Tunisia. Tocopherols, carotenoids and fatty acid content of the fixed oils were determined. The highest carotenoid content was exhibited by Feija oil (10.57 mg/kg of oil). Oueslatia and Tabarka oils displayed the highest alpha-tocopherol content (96.79 and 92.79 mg/kg of oil, respectively). Three major fatty acids were determined: oleic, palmitic and linoleic acids. Oleic acid was the main fatty acid presenti…
Response of soil bacterial communities to the incorporation of crop residues : influence of agricultural practices and link with the soil biological …
2010
The effect of the location of wheat residues (soil surface vs. incorporated in soil) on their decomposition and on soil bacterial communities was investigated by the means of a field experiment. Bacterial-Automated Ribosomal Intergenic Spacer Analysis (B-ARISA) of DNA extracts from residues, detritusphere (soil adjacent to residues), and bulk soil evidenced that residues constitute the zone of maximal changes in bacterial composition. However, the location of the residues influenced greatly their decomposition and the dynamics of the colonizing bacterial communities. Sequencing of 16S rRNA gene in DNA extracts from the residues at the early, middle, and late stages of degradation confirmed …
Response of soil bacterial communities to the incorporation of crop residues : influence of agricultural practices and link with the soil biological …
2010
The effect of the location of wheat residues (soil surface vs. incorporated in soil) on their decomposition and on soil bacterial communities was investigated by the means of a field experiment. Bacterial-Automated Ribosomal Intergenic Spacer Analysis (B-ARISA) of DNA extracts from residues, detritusphere (soil adjacent to residues), and bulk soil evidenced that residues constitute the zone of maximal changes in bacterial composition. However, the location of the residues influenced greatly their decomposition and the dynamics of the colonizing bacterial communities. Sequencing of 16S rRNA gene in DNA extracts from the residues at the early, middle, and late stages of degradation confirmed …