Improving traditional fermented beverages: How to evolve from spontaneous to directed fermentation

Abstract

Fermented foods and beverages are an intrinsic part of our diet. All over the world, regional quality products are produced by native microorganisms in their natural ecosystems, giving the basis for registering appellations of origin. For wines, premium quality products can be obtained by spontaneous fermentation; its success depends heavily on environmental conditions. Inoculated fermentations with selected pure cultures have been developed as alternative; however, the products obtained have a plain aromatic profile compared to those obtained by successful spontaneous fermentations. Several studies have shown that inoculums of native mixed cultures are able to exalt the peculiarities (aroma, structure, and color) of a wine, and preserve their authenticity and uniqueness; however, reliable methods for native microorganism selection are still limited. Currently, the strain selection criterion is based on their genetic endowment; but, the design of an efficient fermentation process requires also knowledge on physicochemical effectors to maximize the metabolic capacity of the selected strains. This article reviews the guidelines for strain selection, and discusses directions for exploring the use of these microorganisms specifying their operating conditions. The main goal of this work is to present the strategy of how to evolve a spontaneous fermentation to directed fermentation.