Non-Saccharomyces yeasts as bioprotection in the composition of red wine and in the reduction of sulfur dioxide.

Non- Saccharomyces yeasts have been used for many years due to their technological potential, particularly as a "booster" of wine fruity aroma in mixed fermentations with Saccharomyces cerevisiae. Recently, a new application has emerged, bioprotection, which consists in colonizing the environment in the context of sulfite reduction in wines. The chemical and sensory impact of non- Saccharomyces yeast according to different modes of application in a context of fermentation without addition of SO 2 was evaluated through trial with Merlot N. (Vitis vinifera L.). An effective niche occupation by non- Saccharomyces yeasts was highlighted during the prefermentary stages by Quantitative-PCR and MALDI-TOF MS identification. Chemical analysis (GC-MS and GC MS/MS) of finish wine showed the significant impact of the dose applications, with bioprotection characterized by linear esters and sequential application by acetates of higher alcohol contents. Moreover, a separation according to the species used in bioprotection was revealed. Finally, using a panel trained, the sensory analysis confirmed that the use of non- Saccharomyces yeast was a fruity booster in sequential inoculation and, to a less extent, when used as bioprotection. This study shows for the first time that the use of non- Saccharomyces yeast as a bioprotection has a significant impact on the aromatic profile of wines. • Occupying the niche by T. delbrueckii as a bioprotection, unlike S. cerevisiae. • The dosage of non- Saccharomyces significantly impact the chemical composition of red wine. • Impact of bioprotection on the chemical and aromatic profile red wine in low SO 2. [ABSTRACT FROM AUTHOR]