Search results for "odor"
showing 10 items of 569 documents
Influence of Physicochemical Interactions between Amylose and Aroma Compounds on the Retention of Aroma in Food-like Matrices
2002
In food matrices, where starch is often used as a gelling or texturing agent, the occurrence of amylose-aroma complexes and their effect on the release of aroma compounds are difficult to determine. Indeed, thick or gelled systems are known to reduce the diffusion rate of flavor molecules, resulting in an increase of retention. Moreover, interactions between aroma compounds and matrix components might increase the retention of aroma compounds. The complexing behavior of three aroma compounds with amylose was studied by DSC and X-ray diffraction to determine the relative importance of these two factors. Their interaction properties were different: two of them formed complexes, and the third …
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…
Site-directed mutagenesis of odorant-binding proteins
2020
Modifying the affinity of odorant-binding proteins (OBPs) to small ligands by replacement of specific residues in the binding pocket may lead to several technological applications. Thanks to their compact and stable structures, OBPs are currently regarded as the best candidates to be used in biosensing elements for odorants and volatiles detection. The wide and rich information on the structure of these proteins both in their apo-forms and in complexes with specific ligands provides guidelines to design reliable mutants to monitor specific targets. The same engineered proteins may also find applications in the slow release of pheromones and other chemicals in the environment, as well as in …
Effects of Cooking Method upon Flavor of Carrots and Peas
1987
Two modalities of pressure (atmospheric pressure and high-pressure of 5.5.104 Pa) and two modalities of immersion (boiling and cooking in steam) were combined factorially to produce four ways of cooking. These different cooking methods were studied on two vegetables: carrots and peas. Sensory attributes of samples were assessed on an unstructured scale. Steam-cooked vegetables have higher sensory attributes (odor and flavor intensities, typical odor and flavor notes, sweetness). Larger losses of soluble solids and volatiles are believed to account for these differences between vegetables cooked in water and cooked in steam.
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…
Behavior of Flavor Compounds in Model Food Systems: a Thermodynamic Study
2003
Physicochemical parameters, such as hydrophobicity, water solubility, and volatility, of four flavor compounds (ethyl acetate, ethyl butyrate, ethyl hexanoate, and 2-pentanone) were determined. The amount of flavor compounds released from different model matrices (mineral water, purified triolein, an oil-in-water emulsion, a carbohydrate matrix, and a complex matrix containing lipids and carbohydrates) into the gaseous phase was determined at thermodynamic equilibrium, at 37 degrees C, by static headspace gas chromatography. The degree of interaction between the flavor compounds and the matrix components was shown by measuring the percentage retention using the water matrix as the reference…
Identification of volatile synomones, induced by Nezara viridula feeding and oviposition on bean spp., that attract the egg parasitoid Trissolcus bas…
2004
Bean plants ( Vicia faba L. and Phaseolus vulgaris L.) damaged by feeding activity of Nezara viridula (L.) ( Heteroptera: Pentatomidae), and onto which an egg mass had been laid, produced volatiles that attracted the egg parasitoid Trissolcus basalis (Wollaston) (Hymenoptera: Scelionidae). Extracts of volatiles of broad bean and French bean plants induced by adults of N. viridula as a result of their feeding activity, oviposition activity, and feeding and oviposition activity combined were analyzed by gas chromatography-mass spectrometry (GC-MS), and tested in Y-tube olfactometer bioassays as attractants for T. basalis females. In extracts from undamaged leguminous plants, green-leaf volati…
Analysis of eicosapentaenoic and docosahexaenoic acid geometrical isomers formed during fish oil deodorization.
2006
International audience; Addition of long-chain polyunsaturated fatty acids (LC-PUFAs) from marine oil into food products implies preliminary refining procedures of the oil which thermal process affects the integrity of LC-PUFAs. Deodorization, the major step involving high temperatures, is a common process used for the refining of edible fats and oils. The present study evaluates the effect of deodorization temperature on the formation of LC-PUFA geometrical isomers. Chemically isomerized eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were used as reference samples. Fish oil samples have been deodorized at 180, 220 and 250 °C for 3 h and pure EPA and DHA fatty acid methyl esters…
Comparison of different methods: static and dynamic headspace and solid-phase microextraction for the measurement of interactions between milk protei…
2002
Interactions between 10 aroma compounds from different chemical classes and 5 mixtures of milk proteins have been studied using static or dynamic headspace gas chromatography and solid-phase microextraction (SPME). Static headspace analysis allows the quantification of the release of only the most abundant compounds. Dynamic headspace analysis does not allow the discrimination of flavor release from the different protein mixtures, probably due to a displacement of headspace equilibrium. By SPME analysis and quantification by GC-MS (SIM mode) all of the volatiles were quantified. This method was optimized to better discriminate aroma release from the different milk protein mixtures and then …
Determination of key odorant compounds in freshly distilled Cognac using GC-O, GC-MS, and sensory evaluation
2004
This aim of this work was to identify the odorant compounds responsible for the typical sensory descriptors attributed to freshly distilled Cognac spirits, not matured in barrels. Panelists were first selected and trained for gas chromatography−olfactometry. Among the 150 volatile compounds identified by gas chromatography−mass spectrometry analysis, only 34 are mainly responsible for the odors detected in the spirits. The “butter” descriptor is explained by the presence of diacetyl, the “hay” descriptor by nerolidol, the “grass” descriptor mainly by Z-3-hexen-1-ol, but also by other compounds, the “pear” and “banana” descriptors by 2- and 3-methylbutyl acetates, the “rose” descriptor by 2-…