marzo 2014

Determination of the Optimum Sun-Drying Time for Vitis vinifera L. cv. Tempranillo Grapes by E-nose Analysis and Characterization of Their Volatile Composition

Lopez De Lerma, N., Moreno, J., Peinado, R.Lopez De Lerma, N., Moreno, J., Peinado, R.

Accede

Abstract

Differences in volatile composition between musts from Tempranillo grapes sun dried for a variable length of time were studied. Volatile aroma compounds clustered into aroma series according to specific odour descriptors. Sun drying decreased the contents in C6 alcohols and aldehydes, which are associated to a cut grass odour, at an early stage and significantly increased those in compounds with spice and ripe fruit odours at a late stage. Cluster analysis with aroma series as classifying factor revealed that the drying process involves two distinct stages where grapes are dehydrated by less than 14 % and more than 25 %, respectively. Principal component analysis with aroma series as classifying factor showed the herbaceous series to account for the differences between the two stages. Finally, principal component analysis of measurements made with an electronic nose (E-nose) revealed that the results were quite similar to those obtained from the chemical determinations. Therefore, an E-nose can be an effective tool for characterising the volatile composition of must with a view to determining the optimum grape-drying time for producing sweet wines

E-nose Sweet wines Tempranillo raising grapes Volatile composition