Search results for "Veterinary"
showing 10 items of 3026 documents
Interactions between aroma compounds and beta-lactoglobulin in the heat-induced molten globule state
2010
; he present study aims to elucidate the binding of small hydrophobic ligands onto the molten globule state of β-lactoglobulin (BLG). The conversion of the native BLG into a molten globule state was induced by heat treatment at acidic pH. The molten globule state was evidenced by far and near-UV circular dichroism spectra. β-Ionone and guaiacol exhibited a higher binding ability to BLG in the heat-induced molten globule state compared to unheated BLG, as assessed by protein surface hydrophobicity measurements, using 6-propionyl-2-(dimethylamino)naphthalene (PRODAN) fluorescent probe. The binding sites of the two aroma compounds were determined by 2D nuclear magnetic resonance (NMR) spectro…
The foaming properties of camel and bovine whey: The impact of pH and heat treatment
2018
International audience; he effect of heat treatment (70 degrees C or 90 degrees C for 30 min) on the foaming and interfacial properties of acid and sweet whey obtained from bovine and camel fresh milk was examined. The maximum foamability and foam stability were observed for acid whey when compared to sweet whey for both milks, with higher values for the camel whey. This behavior for acid whey was explained by the proximity of the pI of whey protein (4.9-5.2), where proteins were found to carry the lowest negative charge as confirmed by the zeta potential measurements. Interfacial properties of acid camel whey and acid bovine whey were preserved at air water interface even after a heat trea…
Effect of Ligands on HP-Induced Unfolding and Oligomerization of β-Lactoglobulin
2020
ABSTRACTTo probe intermediate states during unfolding and oligomerization of proteins remains a major challenge. High pressure (HP) is a powerful tool for studying these problems, revealing subtle structural changes in proteins not accessible by other means of denaturation. Bovine β-lactoglobulin (BLG), the main whey protein, has a strong propensity to bind various bioactive molecules, such as retinol and resveratrol, two ligands with different affinity and binding sites. By combining in situ HP-small-angle neutron scattering (SANS) and HP-UV/visible absorption spectroscopy, we report the specific effects of these ligands on 3D conformational and local changes in BLG induced by HP. Dependin…
Flavor release from salad dressings: sensory and physicochemical approaches in relation with the structure
2000
The effect of process and formulation on sensory perception and flavor release was investigated on salad dressing models. Oil/vinegar emulsions (φ = 0.5, droplet size > 10 μm) with thickeners and a whey protein concentrate were prepared with different fat droplet sizes and different distributions of fat droplet size. The effect of the amount of emulsifier was also tested. Sensory profile analysis was performed by a trained panel and flavor release quantified by dynamic headspace analysis. When the droplet size is increased, the lemon smell and citrus aroma significantly increase, whereas the egg note, mustard, and butter aroma significantly decrease. The concentrations of alcohols and acids…
Sensory and chemical drivers of wine minerality aroma: An application to Chablis wines
2017
The goal of this work was to evaluate the effect of vineyard position on the minerality of wines and to establish relationships between minerality scores, sensory descriptors and chemical composition. Sensory analyses included minerality rating and free description performed by wine professionals under two conditions: orthonasal olfaction alone and global tasting. Chemical characterization included analysis of major and minor volatile compounds, volatile sulphur compounds, mercaptans, metals, anions and cations. Results showed a significant effect of the river bank on wine minerality scores only in the orthonasal olfaction condition, samples from the left being more mineral than those from …
Volatile phenol determination in wine
1981
International audience
Sensory drivers of intrinsic quality of red wines
2013
Abstract The present study aims at evaluating the effect of culture and level of expertise on the perception of wine intrinsic quality. Therefore, regular consumers (108) and experts (119) from La Rioja (RJ-Spain) and Cotes du Rhone (CdR-France) evaluated the intrinsic quality of 12 red wines from both regions. Participants had to categorise the wines according to four levels of quality going from very low to very high quality. Results show no significant correlation between the quality scores given by experts and regular consumers whereas judgments given by French and Spanish experts are significantly correlated as are consumers' quality judgments. This demonstrates that perceived intrinsi…
The role of olfaction in the elaboration and use of the Chardonnay wine concept
2005
The existence of a Chardonnay wine concept was explored in two experiments. In the first experiment, 28 Chardonnay wine experts assessed in terms of a score the degree of representativeness of 48 white wines according to their own Chardonnay wine concept. The samples were 29 wines made from Chardonnay grapes and 19 wines made from other grape varieties (Aligote, Melon de Bourgogne, Sylvaner, Sauvignon blanc, Chenin, Marsanne and Pinot blanc). Two assessment conditions were conducted: orthonasal and global (orthonasal plus retronasal and mouthfeel perceptions). Globally, scores were higher for Chardonnay wines than for non-Chardonnay ones and the consensus among experts demonstrated the exis…
Conceptual vs. perceptual wine spaces: Does expertise matter?
2008
Abstract This study explores the differences in wine categorization between wine experts and novice wine consumers using 10 Melon de Bourgogne (MB) and 10 Chardonnay (CH) wines. Participants performed a free sorting task based on odor similarity followed by a CH and a MB typicality rating task and a liking rating. All tasks were performed orthonasally. We observed a clear agreement between experts concerning typicality scores. Moreover, despite a slight overlap we found a clear differentiation between CH and MB for experts’ typicality scores. For novices, no such agreement on typicality scores was observed and we found a complete overlap between both types of wines. These results suggest th…
Contribution of the Temporal Dominance of Sensations (TDS) method to the sensory description of subtle differences in partially dealcoholized red win…
2009
Abstract In this study, effect of partial alcohol reduction on the sensory modification of red wines was investigated. A Merlot and a Syrah wine were partially dealcoholized using reverse osmosis technique to span a range of three different alcohol contents (14–10%) by grape variety. Preliminary triangle tests indicated the existence of very slight differences between the dealcoholized wines of the study. Therefore, adapted descriptive methodologies had to be used. In a first step, wines were described with a comparative sensory profile by 16 trained panellists on 15 sensory attributes. Then, the same panellists profiled the wines with the TDS technique, which consists in identifying and ra…