Effect of Candida zemplinina oak chips biofilm on wine aroma profile

The cultivated area of table grapes worldwide has experienced a paramount increase over the last two decades. In this current scenario, traditional varieties are being replaced by new cultivars that prioritize a profitable and sustainable agriculture, while satisfying consumer demands. It is widely recognized that wine varieties, especially those with red berry flesh, are renowned for their high antioxidant capacity and phenolic compounds, which promote health. Recently, this topic has also gained significance in table grape breeding programs.

From a fertility standpoint, the vine has to extract from the soil mineral substances necessary for its existence. However, the amount of certain available nutrients does not always correspond to a proportional increase in quality.

Bases on oxoluminescence, we have developed an innovative device for measuring dissolved oxygen in wines in barrels without opening the bung. This system is directly inserted into the wood during the barrel elaboration and can be positioned at different locations of the barrel (the head, the hull …). During two successive vintages we have used this device notably to follow the oxygen dissolved of whites wines elaborated in barrels. This allowed us initially to monitor the oxygen levels of the harvest to bottling the whole elaboration process in barrels of white wines without using techniques of measurement suitable to modify the real values in wines (opening the bung to plunge an oximeter).

Although there are detailed studies on the microbiota of Vitis vinifera L. grapes, little is known about the diversity of yeast communities present in non-vinifera Vitis ecosystems (i.e., grapes and spontaneously fermenting grape musts). Potentially scientific and/or enological valuable yeast strains from these non-vinifera Vitis ecosystems might never be isolated from V. vinifera L. Using a standard culture-dependent strategy, we studied the population of yeast species during initial stages of spontaneous fermentation of V. labrusca L. (Isabella) grape musts. Rare non-Saccharomyces yeast species were recognized in Isabella, including Candida azymoides, Pichia cecembensis, Candida californica, Candida bentonensis, Issatchenkia hanoiensis and Candida apicola.

Oenological tannins are classified as hydrolysable and condensed tannins. Their use in winemaking is only authorized, to facilitate wine fining. Nevertheless, tannins could also be used to prevent laccase effects.