RT Journal Article
SR Electronic
T1 Stilbenes Can Impair Malolactic Fermentation with Strains of <em>Oenococcus oeni</em> and <em>Lactobacillus plantarum</em>
JF American Journal of Enology and Viticulture
JO Am J Enol Vitic.
FD American Society for Enology and Viticulture
SP ajev.2020.20021
DO 10.5344/ajev.2020.20021
A1 Sabrina Zimdars
A1 Rita Caspers-Weiffenbach
A1 Pascal Wegmann-Herr
A1 Fabian Weber
YR 2020
UL http://www.ajevonline.org/content/early/2020/10/06/ajev.2020.20021.abstract
AB Malolactic fermentation (MLF) is an important step in winemaking to improve wine quality by deacidification, increased microbial stability, and modified wine flavor. The phenolic composition of the wine influences the growth and metabolism of lactic acid bacteria (LAB) used for MLF. Due to an increased cultivation of fungus-resistant grape cultivars, the present study aimed to analyze the influence of stilbenes on MLF, since stilbenes play an important role as phytoalexins in plants to counteract fungal pathogens. It was shown that the grapevine-shoot extract Vineatrol® and the stilbenes ε-viniferin, ampelopsin A, r2-viniferin , r-viniferin , as well as mixtures of the five stilbenes, decelerated malic acid degradation. This can be partially attributed to a reduced number of viable cells but the direct impact of stilbenes on the malolactic enzyme also has to be accounted for. This was deduced from a stabilized viability of LAB, while at the same time, malic acid degradation was reduced. These results show that wines made from stilbene-rich grapes like fungus-resistant cultivars might have a higher risk for a sluggish or incomplete MLF.