Use of non-conventional yeast improves the wine aroma profile of Ribolla Gialla

Abstract

Consumer wine preferences are changing rapidly towards exotic flavours and tastes. In this work, we tested five non-conventional yeast strains for their potential to improve Ribolla Gialla wine quality. These strains were previously selected from numerous yeasts interesting as food production candidates. Sequential fermentation of Ribolla Gialla grape juice with the addition of the Saccharomyces cerevisiae T73 Lalvin industrial strain was performed. Zygosaccharomyces kombuchaensis CBS8849 and Kazachstania gamospora CBS10400 demonstrated positive organoleptic properties and suitable fermentation dynamics, rapid sugar consumption and industrial strain compatibility. At the same time, Torulaspora microellipsoides CBS6641, Dekkera bruxellensis CBS2796 and Dekkera anomala CBS77 were unsuitable for wine production because of poor fermentation dynamics, inefficient sugar consumption and ethanol production levels and major organoleptic defects. Thus, we selected strains of K. gamospora and Z. kombuchaensis that significantly improved the usually plain taste of Ribolla wine by providing additional aromatic complexity in a controlled and reproducible manner.

Microbial Resources and Enological Significance: Opportunities and Benefits

“…It can contribute to increase flavor intensity’ and several ‘fruity’ attributes in Ribolla Gialla (Dashko et al, 2015), as well as benzaldehyde in Sauvignon Blanc and Syrah (Whitener et al, 2015) wines.…”

Microbial and Chemical Diversity of Traditional Non-Cereal Based Alcoholic Beverages of Sub-Saharan Africa

“…The natural microbial flora in the raw material (substrate) may not always be the same just as the substrate will vary depending on different environmental conditions. The secondary metabolites formed during oxidation of the fruit acids and alcohols post-fermentation lead to difficulty in production of a product with consistent characteristics [63,64]. This variance in taste and aroma is inherent and akin to differences of wine bouquets.…”

“…For example, the use of S. cerevisiae and T. delbrueckii lead to the production of beverages with elevated levels of higher alcohols, ethyl acetate and isoamyl acetate, and lower levels of ethyl hexanoate and ethyl octanoate [61] thus enhancing the taste and flavor. In the wine industry starter cultures are dominated by Saccharomyces species, but the need for new tastes to sort customer demands have presented great potential for non-Saccharomyces species to be used as part of the microbial consortia for fermentation [63,68]. To improve product quality and facilitate the production of a consistent product, the commercialization of non-cereal-based alcoholic beverages would therefore require cultures made up of microbial consortia.…”

“…Like any other alcoholic beverages, the conversion of the sugary substrate leads to increased nutritional components. The aromatic complexity of the wine is due to the production of compounds produced such as esters, carbonyls, alcohols, phenols, acids, sulphur compounds, terpenes, hydrocarbons, nitrogen compounds, and lactone [63,79,80,126].…”

“…The honey wine is also produced and consumed in Cameroon where it is known as kuri [129]. Tree barks or roots of some plants or herbal ingredients are added to improve the flavor whereas the fermentation pot is seasoned by smoking over smoldering Rhamnus prinoides stems and olive wood [17,63]. Fermentation is run for 5 days, in warm weather, or for 15 to 20 days, in colder cases [27].…”