Macrowine 2021
IVES 9 IVES Conference Series 9 Effect of non-Saccharomyces yeast and lactic acid bacteria on selected sensory attributes and polyphenols of Syrah wines

Effect of non-Saccharomyces yeast and lactic acid bacteria on selected sensory attributes and polyphenols of Syrah wines

Abstract

Consumers predominantly use visual, aromatic and texture cues as quality/preference indicators to describe olfactory sensations. In this study, the effect of micro-organism in wine production was investigated using analytical and sensory techniques to achieve relevant analytical characterisation. Selected anthocyanins, flavan-3-ols, flavonols and phenolic acids were quantified in Syrah wines using RP-HPLC-DAD. Standard oenological parameters were also measured. Syrah grape must was fermented with various combinations of Saccharomyces cerevisiae (S. cerevisiae) and non-Saccharomyces (Metschnikowia pulcherrima or Hanseniaspora uvarum) yeasts, which was followed by sequential inoculation of lactic acid bacteria (LAB) (Oenococcus oeni or Lactobacillus plantarum). Phenolic, sensory and oenological data were positively correlated where the phenolic data differentiated S. cerevisiae yeast, non-Saccharomyces yeast and LAB. Increased phenolic compound concentrations were evident in Syrah wines made with a combination of Saccharomyces, non-Saccharomyces and LAB, compared to wines made with S. cerevisiae only. Wines produced with S. cerevisiae, M. pulcherrima and Oenococcus oeni were higher in flavan-3ols, flavonols and phenolic acids, compared to control wines that were produced using Saccharomyces cerevisiae yeasts only. Syrah wines made with S. cerevisiae, M. pulcherrima and L. plantarum were higher in total anthocyanins, compared to wines inoculated with S. cerevisiae only. The wine sensory attributes, i.e. body and astringency, correlated positively with a combination of LAB and yeast treatments. Wines made with a combination of yeast and bacteria also scored high in overall wine quality. It was shown that S. cerevisiae retained more phenolic compounds during fermentation when compared to wines made with a combination of yeast and LAB treatments during fermentation. Wines produced with non-Saccharomyces yeasts combinations contained lower alcohol levels, compared to wines produced with S. cerevisiae only. None of the treatments produced high VA levels.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Phillip Minnaar*, Heinrich Du Plessis, Neil Jolly, Veruscha Paulsen

*Agricultural Research Council

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

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