An Integrative View of the Role of Lachancea thermotolerans in Wine Technology

Abstract

The interest in Lachancea thermotolerans, a yeast species with unusual characteristics, has notably increased in all ecological, evolutionary, and industrial aspects. One of the key characteristics of L. thermotolerans is the production of high quantities of lactic acid compared to other yeast species. Its evolution has mainly been driven by the influence of the environment and domestication, allowing several metabolic traits to arise. The molecular regulation of the fermentative process in L. thermotolerans shows interesting routes that play a complementary or protective role against fermentative stresses. One route that is activated under this condition is involved in the production of lactic acid, presenting a complete system for its production, showing the involvement of several enzymes and transporters. In winemaking, the use of L. thermotolerans is nowadays mostly focused in early–medium-maturity grape varieties, in which over-ripening can produce wines lacking acidity and with high concentrations of ethanol. Recent studies have reported new positive influences on quality apart from lactic acid acidification, such as improvements in color, glutathione production, aroma, malic acid, polysaccharides, or specific enzymatic activities that constitute interesting new criteria for selecting better strains. This positive influence on winemaking has increased the availability of commercial strains during recent years, allowing comparisons among some of those products. Initially, the management of L. thermotolerans was thought to be combined with Saccaharomyces cerevisiae to properly end alcoholic fermentation, but new studies are innovating and reporting combinations with other key enological microorganisms such as Schizosaccharomyces pombe, Oenocous oeni, Lactiplantibacillus plantarum, or other non-Saccharomyces.

Biocontrol potential of wine yeasts against four grape phytopathogenic fungi disclosed by time-course monitoring of inhibitory activities

“…pullulans strains exhibiting the highest diversity of lytic enzymes released, in line with the recognized ability of this species (Bozoudi and Tsaltas, 2018). On the other hand, glucanase activity was highly frequent in our L. thermotolerans strains, a feature that has been previously identified for this species (Romo-Sánchez et al, 2010), although it is considered rare (Vicente et al, 2021). Nevertheless, the role of these hydrolytic enzymes on the inhibitory activity of these species was unclear, as no enhanced antagonism was detected in CY assays.…”

Acetic Acid Bacteria in Sour Beer Production: Friend or Foe?

“…Strain selection is of major importance, since large within-species and -strain variations occur, which greatly influences the final products ( Osburn et al, 2018 ; Gatto et al, 2020 ). A high variability has been reported regarding lactic acid and ester production, flavor formation, sourness perception, and final pH ( Domizio et al, 2016 ; Gamero et al, 2016 ; Osburn et al, 2018 ; Gatto et al, 2020 ; Vicente et al, 2021 ). Brewing primary-soured beers has the additional advantage of being produced without blocking the brewing kettle for days.…”

Forests influence yeast populations vectored by insects into vineyards

“…Another species consistently found in insects’ guts, Hanseniaspora uvarum , can influence the complexity and richness of yeast populations by competing with other fungi such as Botrytis cinerea and can confer fruity aromas and other organoleptic characteristics to the wine ( Guaragnella et al, 2020 ). An additional example of yeast species of oenological interest found in wasp intestines is Lachancea thermotolerans : strains of this species can produce lactic acid and ethanol through alcoholic fermentation, hence showing great potential for the production of less acidic wines ( Vicente et al, 2021 ).…”