Toasted Vine-Shoots As An Alternative Enological Tool. Impact On The Sensory Profile Of Tempranillo Wines

Abstract

The use of toasted vine-shoots as an alternative enological tool to make differentiated wines has generated interest among researchers and wineries. However, the evolution of these wines in bottle and the effect on the sensory profile has not been studied so far.

In this work, Tempranillo wines were elaborated in contact with their own toasted vine-shoots fragments in two different doses and two moments of addition: in the middle of alcoholic fermentation (1/2AF) and after malolactic fermentation (AMF). After removing vine-shoots, the wines were bottled, and a sensory analysis was carried out over a year using a specific scorecard which included color, olfactory and taste descriptors. Also, along with the traditional odor descriptors, a new one, named SEGs (Shoot from vines – Enological – Granule), was included to describe the specific impact of the vine-shoots. Besides, the phenolic and volatile compositions of wines were analyzed by HPLC-DAD and SBSE-GC-MS, respectively.

Results of the statistical analysis showed a greater contribution of the vine-shoots addition moment than doses in the wines sensory differentiation. The sensory analysis at bottling time showed that vine-shoots only modified the color in AMF wines, having more violet tones than the control. However, after 120 days in bottle, the garnet and red tones were upwards, being greater than in the control wine. This suggests a better evolution of wines macerated with lower doses of toasted vine-shoots.

Regarding to odor descriptors, wines from treatments showed at the end of winemaking higher values than control wine, except for red fruit notes. At bottling time, the notes of nuts, toast and SEGs were the most important in AMF wines with respect to the control. However, along time in bottle, the differences of these descriptors with respect to the control decreased in AMF wines and slightly increased in 1/2AF ones.

Concerning taste descriptors, at bottling time wines from treatments showed higher values than control, mainly in AMF wines, where nuts, toast and SEGs nuances were the most intense. However, there were differences in the bottle evolution between wines from treatments, which slightly enhanced of several descriptors in 1/2AF but decreased in AMF wines, which suggests a better integration of the vine-shoots in the wine in the last case. On the other hand, tannins of wines from vine-shoots treatments were described by tasters as sweetness, non-dryness and non-bitterness since the first tasting, contrary to control ones, where dryness and bitterness were appreciated up to 120 days in bottle.

Finally, after a year in the bottle, the differentiation in the sensory profile of the wines was maintained, although the aromatic nuances were softened.