Non Saccharomyces wine yeasts: emerging trends and challenges in winemaking

Yeasts serve as highly versatile tools in oenology. They do more than just perform alcoholic fermentation. Nowadays, yeasts from various species, naturally present in grapes, are selected for specific non-fermentative applications. For example, the use of selected non-saccharomyces at the early stage of winemaking has become a common practice to limit the growth of unwanted microorganisms. When inactivated, yeasts can be fractionated into soluble and insoluble fractions providing a wide range of benefits related to structural components or specific metabolites.

The use of toasted vine-shoots as an alternative enological tool to make differentiated wines has generated interest among researchers and wineries. However, the evolution of these wines in bottle and the effect on the sensory profile has not been studied so far.

In the Northeast of Brazil, vines can produce twice a year, because annual average temperature is 26ºC, with high solar radiation and water availability for irrigation.

The total global production of wine in 2021 was estimated at around 250 million hectoliters. The 30% of the total quantity of vinified grapes corresponds to wine by-products that represent nearly 20 million tons, of which 50% corresponds to the European Union. Wine by-products have been used for different purposes, in agriculture, cosmetics, pharmacy, biorefinery, feed, and the food

Insufficient levels of malate and lack of acidity in commercial grape cultivars (V.vinifera) hinders the quality of fruit grown in warm climates. Conversely, excessive levels of malate and sourness in wild Vitis grape, leads to unpalatable fruit and complicates the introgression of valuable disease resistant alleles through breeding. Nonetheless, albeit decades of research, knowledge regarding the molecular regulation of malate levels in grape remains limited.