Development of Novel Yeast Derivatives from Starmerella bacillaris to Improve Sustainability in the Wine Industry

Historically underutilized, non-Saccharomyces yeasts have emerged as vital biotechnological tools, enhancing wine quality and addressing challenges posed by climate change, such as increased sugar content and reduced aromatic complexity in grapes. Beyond their fermentative role in winemaking, non-Saccharomyces species can also serve as a platform for the development of yeast derivatives, biotechnological tools finding applications in different sectors. Known for its ability to modulate wine acidity, enhance glycerol production, and reduce ethanol content, Starmerella bacillaris was chosen among non-Saccharomyces species as a promising candidate for creating innovative yeast derivatives. This study aimed to produce and test yeast derivatives from S. bacillaris within an industrially applicable framework. A fed-batch cultivation strategy was employed to propagate different strains of S. bacillaris along with the control benchmark species S. cerevisiae. Yeast biomass was further processed to obtain yeast fractions to be used in derivative production. Three extraction methods—autoclaving, enzymatic hydrolysis, and alkaline treatment—were applied to the yeast cell walls, yielding diverse yeast derivatives. Compositional characterization revealed significant differences between S. bacillaris and S. cerevisiae products. The different derivatives obtained were ultimately tested in winemaking applications, particularly focusing on white wine protein stability issues. Further applications tested included antioxidant activity and interactions with lactic acid bacteria. A preliminary evaluation of the immunomodulatory properties of these derivatives further confirmed the promising potential of S. bacillaris as a source of high-value derivatives in oenology and beyond, with applications spanning food, biomedical, and health-related industries.