Off-flavors produced by undesirable microbial spoilage are a major concern in wineries, as they affect wine quality. This situation is worse in warm areas affected by global warming because of the resulting higher pHs in wines. Natural biotechnologies can aid in effectively controlling these processes, while reducing the use of chemical preservatives such as SO2.
Bioacidification reduces the development of spoilage yeasts and bacteria, but also increases the amount of molecular SO2, which allows for lower total levels. The use of non-Saccharomyces yeasts, such as Lachancea thermotolerans, results in effective acidification through the production of lactic acid from sugars. Furthermore, high lactic acid contents (>4 g/L) inhibit lactic acid bacteria and have some effect on Brettanomyces.
Additionally, the use of yeasts with hydroxycinnamate decarboxylase (HCDC) activity can be useful to promote the fermentative formation of stable vinylphenolic pyranoanthocyanins, reducing the amount of ethylphenol precursors. This biotechnology increases the amount of stable pigments and simultaneously prevents the formation of high contents of ethylphenols, even when the wine is contaminated by Brettanomyces.
This open access review is focused on the elimination of off-flavors by using non-Saccharomyces yeasts that are able to control pH by bioacidification or to decrease the concentration of precursors of molecules responsible for sensory defects. The review is structured as follows:
- Introduction
- Bioprotection
- Bioacidification by Lanchancea thermotolerance
- Apiculate yeasts and volatile acidity
- Biocompatibility
- Depletion of off-flavour precursors
- Increasing the implantation of non-Saccharomyces as bioprotective tools using emerging non-thermal technologies
REFERENCE
Morata, Antonio, Iris Loira, Carmen González, and Carlos Escott. 2021. “Non-Saccharomyces as Biotools to Control the Production of Off-Flavors in Wines” Molecules 26, no. 15: 4571. https://doi.org/10.3390/molecules26154571
This is a reproduction of original text from the cited published article as permitted by the open access policy of the journal Molecules.
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