Yeasts for low input winemaking: Microbial terroir and flavor differentiation

Abstract

Vitis vinifera flowers and grape fruits are one of the most interesting ecosystem niches for native yeasts development. There are more than a 100 yeast species and millions of strains that participate and contribute to design the microbial terroir. The wine terroir concept is understood when grape and wine micro-regions were delimited by different quality characteristics after humans had been growing vines for more than 10,000 years. Environmental conditions, such as climate, soil composition, water management, winds and air quality, altitude, fauna and flora and microbes, are considered part of the "terroir" and contribute to a unique wine style. If "low input winemaking" strategies are applied, the terroir effect will be expected to be more authentic in terms of quality differentiation. Interestingly, the role of the microbial flora associated with vines was very little study until recently when new genetic technologies for massive species identification were developed. These biotechnologies allowed following their environmental changes and their effect in shaping the microbial profiles of different wine regions. In this chapter we explain the interesting positive effects on flavor diversity and wine quality obtained by using "friendly" native yeasts that allowed the microbial terroir flora to participate and contribute during fermentation.

Keywords: Fermentation; Grapes; Hanseniaspora vineae; Mixed cultures; Native yeasts; Non-Saccharomyces; Wine flavor.