The cellular symphony of redox cofactor management by yeasts in wine fermentation

Redox metabolism is pivotal in anaerobic fermentative processes such as winemaking where it results in the production of many metabolites that contribute to the aroma and flavour of wine. Key to this system are NAD⁺ and NADP⁺, which play essential roles as cofactors in maintaining cellular redox balance and regulating metabolism during fermentation. This review comprehensively explores redox metabolism under winemaking conditions, highlighting the influence of factors such as oxygen availability and vitamins including B3 and B1. Recent findings underscore the rapid assimilation and recycling dynamics of these vitamins during fermentation, reinforcing their critical role in yeast performance. Despite extensive research, the roles of diverse yeast species and specific vitamins remain insufficiently explored. By consolidating current knowledge, this review emphasises the implications of redox dynamics for metabolite synthesis and overall wine quality. Understanding these metabolic intricacies offers options to enhance fermentation efficiency and refine aroma profiles. The review also identifies gaps in studies for intracellular vitamin metabolism and underlines the need for deeper insights into non-Saccharomyces yeast metabolism. Future research directions should focus on elucidating specific metabolic responses, exploring environmental influences, and harnessing the potential of diverse yeasts to innovate and diversify wine production strategies.