87 research outputs found
Further insights into the floral character of Touriga Nacional Wines
Higher-quality Touriga Nacional (TN) wines are characterized by a fruity-citric aroma described as sweet and fresh citrus evoking the bergamot fruit (Citrus bergamia). In fact, “bergamot-like” descriptor is currently
employed to rate higher quality TN wines. The aim of thiswork was to identify among volatile compounds present in
bergamot fruit extracts (mainly terpenes) which of them contributes the most to the bergamot overall perception, and relate these data with the volatile composition of TN wines. The identification of the most important descriptors was done by sensory analysis. Among 18 descriptors 3were selected: bergamot-like aroma, orange like, and violet. A GCO of a typical TN wine extract allows the identification of 3 related odorant zones ZO1, ZO2, and ZO3 related with bergamot-like aroma. Using AEDA, ZO2 was confirmed to be one of the most important odorant zones. Using AEDA
the presence of linalool and linalyl acetate was confirmed. A similarity test was performedwith a non-TN wine added
with linalool and linalyl acetate alone or in combinations. The highest similarity value was observed when linalool
(SV = 5.9) was added. In fact, results obtained from the analysis of several red wines from different varieties show
that terpenols are present in higher amounts in wines coming from TN variety, which proves that these compounds can be the clue to the varietal aroma of TN wines
Etude et exploitation par voie enzymatique des précurseurs d'arômes du raisin de nature glycosidique
National audienc
Production of a highly glucose-tolerant extracellular beta glucosidase by three Aspergillus strains
International audienc
Aroma compounds of vitis vinifera L. cv. Emir grown in central Anatolia
Free and glycosidically bound aroma compounds of Emir grape juice obtained with or without skin-contact were investigated. The aroma compounds were isolated by adsorbtion on Amberlite XAD-2 resin and analysed by gas chromatography-mass spectrometry (GC-MS). 32 free and 37 glycosidically bound compounds were identified. - Shikimate - derived compounds were major components. C13-norisoprenoid compounds usually detected in bound forms in grapes were also present in free forms in Emir grape. Monoterpenes were in lower levels that normally found in floral grape cultivars. The amounts of free and bound aroma compounds of the juice increased by skin-contact treatment. The levels of some compounds were significantly different in control and skin-contact jices. Additionally, skin-contact treatment resulted in an increase in pH, colour intensity, total phenolics, potassium, sodium and calcium
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