Search results for "aroma"
showing 10 items of 1006 documents
Effect of winemaking process and addition of white grapes on the sensory and physicochemical characteristics of young red wines
2008
Background and Aims: This work studies the effect of winemaking process (carbonic maceration (CM) vs destemming) and the effect of grape variety (100% Tempranillo red grapes vs Tempranillo grapes and Viura white grapes) on sensory and physicochemical characteristics of young red wines from Rioja Alavesa. Methods and Results: Nineteen wines distributed in four groups (the four combinations from the two factors) were collected from 12 wineries. Twenty-four sensory attributes and 15 physicochemical parameters were analysed at four time points through 9 months. Data were analysed by analysis of variance and by canonical variate analysis. CM wines were higher in red berry aroma and flavour, alco…
Effect of micro-oxygenation on the evolution of aromatic compounds in wines: Malolactic fermentation and ageing in wood
2009
Abstract The effect of micro-oxygenation on the aromas of two varietal wines (Tempranillo and Cabernet Sauvignon) when alcoholic fermentation is complete was examined. Several factors, such as whether malolactic fermentation (MLF) took place in barrels or stainless steel vats and ageing time in oak barrels, were taken into account. Major aroma components were studied using GC-FID and minor compounds were studied by GC–MS analysis before and after MLF and after 4 and 8 months of maturation in oak barrels. Sensorial analysis was performed to describe and quantify the different wine notes. Micro-oxygenation affects different compounds but the effect depends to a great extent on the grape varie…
Orthonasal aroma characteristics of Spanish red wines from different price categories and their relationship to expert quality judgements
2012
Background and Aims: Research aimed to define the olfactory sensory spaces of Spanish red wines from different price segments and to determine relationships between sensory descriptors and quality as evaluated by experts. Methods and Results: A trained panel using a frequency of citation method assessed the orthonasal sensory characteristics of 96 Spanish wines belonging to three price segments (premium; high standard; low standard). Eleven robust sensory terms were built by combining similar terms using statistical criteria. A panel of experts consistently assessed quality. Negative aroma profiles, some of them very skewed, were identified in the different sets with 'animal', 'undergrowth'…
Pyroglutamic Acid: A Novel Compound in Wines
2008
Wine contains a complex mixture of nearly 1,000 compounds, which include sugars, acids, alcohols, ketones, aldehydes, esters, amino acids, amines, phenol carbonic acids, flavonoids, anthocyanidins and cathechins. Many of these compounds have an influence on the aroma and bouquet of wine. Identification of wine-related compounds is by far not complete. Recently, pyroglutamic acid has been detected as a so far overlooked novel compound in wine samples, which is described below.
Synthesis of new asymmetric xanthene dyes via catalyst-free SNAr with sulfur nucleophiles
2014
Addition of a single functional handle to the tricyclic moiety of fluorescein results in asymmetric xanthene dyes. Our synthesis of a new class of asymmetric xanthenes proceeds via an unusual SNAr with sulfur nucleophiles on electron rich aromatic xanthenes scaffolds in the absence of a metal catalyst. The resulting 3'-thioethers exhibit high photostability and are conveniently converted into reactive dyes for macromolecule labelling.
ChemInform Abstract: Synthesis of New Asymmetric Xanthene Dyes via Catalyst-Free SNAr with Sulfur Nucleophiles.
2014
Addition of a single functional handle to the tricyclic moiety of fluorescein results in asymmetric xanthene dyes. Our synthesis of a new class of asymmetric xanthenes proceeds via an unusual SNAr with sulfur nucleophiles on electron rich aromatic xanthenes scaffolds in the absence of a metal catalyst. The resulting 3′-thioethers exhibit high photostability and are conveniently converted into reactive dyes for macromolecule labelling.
A HS-SPME-GC-MS analysis of IR heated wood: Impact of the water content on the depth profile of oak wood aromas extractability
2013
http://www.sciencedirect.com/science/article/pii/S0963996913003736; International audience; Controlled and reproducible IR heat treatments were applied to oak wood surfaces in order to establish a depth-profiled picture of the extractability of volatile compounds, with particular emphasis on the impact of the initial water content. Headspace-solid phase microextraction-gas chromatography coupled to mass spectrometry (HS-SPME-GC-MS) has been used to compare the concentrations of six aroma compounds (vanillin, furfural, eugenol; guaiacol and cis- and trans-whisky lactones) in hydroalcoholic extracts of series of slices representative of the first 8 mm of the wood facing the IR source. Results…
Texture-aroma interactions in dairy products: Do in-vivo and in-vitro aroma release explain sensory perception?
2008
International audience; The influence of the texture on perceived aroma intensity and on in-vivo and in-vitro aroma release was investigated on three types of dairy products, prepared with different textures. Aroma release depends on in mouth breakdown of the product. The consequences of a textural modification on aroma perception were not the same for the different products. In the case of liquid to semi-liquid products (yogurt and custard dessert), in-vivo aroma release decreased when viscosity increased. For firm gels (model cheeses) in-vivo aroma release was found to increase when cheese hardness increased, but inverse results were obtained in in-vitro conditions. Thus, aroma release co…
An original approach for gas chromatography-olfactometry detection frequency analysis: Application to gin
2012
Abstract Gas Chromatography-Olfactometry (GC-O) is a technique that lies halfway between physicochemical and sensory analysis and involves the perception of volatile flavour compounds, separated by gas chromatography, by the human nose. Of the different GC-O procedures available, detection frequency has been proved to be more rapid and more repeatable, even with an untrained panel. This characteristic regarding the panel is often not considered when dealing with the sensory attributes determined by assessors. An original approach to GC-O using the detection frequency procedure has been developed and tested on two types of gin and made it possible to benefit from sensory data. The panel cons…
Impact of lipid extraction on the dearomatisation of an Eisenia foetida protein powder
2010
www.elsevier.com/locate/foodchem ; FSTA:2010-Sp0197; International audience; Delipidation was studied as a way to dearomatise a non-conventional protein powder obtained from Eisenia foetida earthworms. In the first step, we studied the impact of several factors such as solvent type, extraction method and particle size on the yield of extracted lipids. Lipid extraction from samples was considerably improved using an ultrasound method with a chloroform/methanol mixture and small particle size. In the second step, the volatile compounds were extracted from the delipidated protein powder by the SAFE extraction method and by the HS-SPME method, and were further analysed by GC-MS. The chloroform/…