Search results for "DSpace"
showing 10 items of 30 documents
Influence of complexation between amylose and a flavored model sponge cake on the degree of aroma compound release
2008
International audience; Flavoring is used in the food industry to reinforce the aroma profile of baked cereal goods. During the processing of such products, interactions between starch and aroma compounds can occur, and this may have an impact on aroma release and perception. In the present study, 20 aroma compounds were tested to establish whether they formed complexes with amylose. The structure of the complexes was determined by wide-angle X-ray scattering (WAXS). A cocomplexation study proved that several complexing compounds could be present in the same crystalline aggregate. WAXS and differential scanning calorimetry (DSC) experiments were performed in a flavored model sponge cake at …
Wine analysis: Study and comparison of techniques developed for the study of volatile constituents
1986
A number of headspace techniques have been compared, using a standard solution containing 12 compounds and a wine sample, viz.: (1) purge and cold trap injection; (2) dynamic headspace combined with liquidliquid extraction; (3) static headspace with and without preconcentration; (4) direct liquid injection. The sensitivity, reproducibility and speed of analysis were determined. Considering the results obtained and dependent on the purpose of the experiments and the number of samples to be examined the appropriate technique can be selected. ?? 1980 Friedr. Vieweg & Sohn Verlagsgesellschaft mbH.
Investigation of cuticular hydrocarbons from Bagrada hilaris genders by SPME/GC-MS
2007
The cuticular hydrocarbons of male and female Bagrada hilaris Burmeister (Heteroptera: Pentatomidae) were investigated, by headspace solid-phase microextraction followed by gas chromatography-mass spectrometry. Measurements were done with fiber coatings of different polarity after optimization of headspace volumes and extraction temperatures. This resulted in the use of polyacrylate fiber, 22-ml vial as the sample holder, and an extraction temperature of 150 degrees C. The analytical procedures allowed identification of 13 peaks, corresponding to a homologous series of n-alkanes (nC(17)-nC(29)). The hydrocarbon profiles of male and female B. hilaris were qualitatively equal, but marked sex-…
Mass spectrometry analysis of volatile compounds in raw meat for the authentication of the feeding background of farm animals.
2007
The authentication of the conditions of animal production, based on the analysis of meat commercial cuts, is a major challenge on both societal and analytical grounds. The aim of the present work was to propose a method for the extraction of the volatile compounds from ruminant raw muscles trimmed of fat and to assess by mass spectrometry-based techniques the relevance of these compounds for the authentication of the type of feeding offered to the animals. The first step of the study consisted of validating conditions of dynamic headspace (DH) extraction of volatile compounds that enabled us to minimize the appearance of heat-induced artifacts and to maximize the richness of the DH-gas chro…
Multivariate approach to reveal relationships between sensory perception of cheeses and aroma profile obtained with different extraction methods
2014
A new and original statistical approach was used to compare the effectiveness of 4 different methods to analyse aroma compounds of seven different commercial semi-hard cheeses with regard to their orthonasal sensory perception. Four extraction methods were evaluated: Purge and Trap, Artificial Mouth, Solid-Phase Microextraction (SPME) and Solvent-Assisted Flavour Evaporation (SAFE). Among the headspace methods, Artificial Mouth gave the closest representation of the studied product space to the sensory perception one. The SAFE method was complementary to the dynamic headspace methods, as it was very efficient in extracting the heavy molecules but less efficient for extracting the most volat…
Ziņojums par DSpace ieviešanu Latvijas Universitātē
2010
Referāts par DSpace ieviešanas procesu gaitu, nolasīts LU konferences "Open Access un OpenAIRE - izaicinājums un iespēja Latvijas zinātnes attīstībai" ietvaros 2010. gada oktobrī
Study of relationships between the structure of aroma compounds and their retention-release between vapour phase and dairy gels
2010
An integrated approach physicochemistry and structures activity relationships has been carried out to study the aroma compounds retention-release phenomenon in a fat free dairy gel added with pectin. This study aimed to identify the molecular properties that govern this phenomenon assuming that modifying the structure leads automatically to a change in the retention-release of aroma compounds. For this purpose, we have determined the partition coefficients of 28 aroma compounds in water, in pectin gels and in dairy gels supplemented or not supplemented with pectin, at equilibrium conditions using the PRV method (Phase Ratio Variation). Then, we have performed a structure-retention relations…
Interactions texture-flaveur : mécanismes physico-chimiques ou mécanismes cognitifs ? Application à un gel laitier onctueux
2006
Texture, taste and aroma are key components of the perceived quality of foodstuffs. Many studies showed that modifying one of thèse dimensions could modify the perception of another one. However it is not always clear whether thèse interactions could be attributed to physico-chemical or cognitive mechanisms. The présent work aimed at studying sensory interactions between texture, taste and aroma, in relation with the perception of creaminess, an indicator of food quality. A first step consisted in defining the creaminess concept using sensory and verbal approaches. This study highlighted three groups of consumers: creaminess was associated to texture for the first group, to texture and tast…
Electrophysiological and behavioral studies to test attractants semiochemicals for Stegobium paniceum L. (Coleoptera: Anobiidae)
2017
Stegobium paniceum (L.) (Coleoptera: Anobiidae), the drugstore beetle, is one of the major pests for a wide variety of dry and durable stored agricultural products. Females of S. paniceum produce a sex pheromone, (2S,3R,1'R)-Stegobinone, that attracts males. Nevertheless, trapping experiments using the synthetic sex pheromone in many cases showed low levels of captures, perhaps because of isomerization of the pheromone compound in ambient conditions. To date, very few brands of commercially S. paniceum pheromone are available in the market. In this study, we evaluated in electrophysiological (EAG) and behavioral bioassays (two-choice olfactometer), the response of S. paniceum male and femal…
Modified Atmosphere Packaging and low temperature storage extend marketability of cherimoya (Annona cherimola Mill.)
2022
Cherimoya is a subtropical fruit characterized by a delicious, sweet flavor and beneficial health properties, which found suitable growing conditions in the South of Italy. However, the marketing of this product is halted by its high perishability, which limits the shelf-life of the fresh fruit to few days after harvest and does not allow for commercialization beyond local markets. Studies have shown that storage of this fruit in controlled atmosphere, using Modified Atmosphere Packaging technologies, extended the post-harvest life of Cherimoya, but little is still known about the evolution of its sensory, nutraceutical and microbiological characteristics during such storage period. In this…