Encapsulated bacteria enhance MLF in stressful environments

Image source: Wikimedia Commons By Karien O'Kennedy The aim of this study was to evaluate the effect of encapsulating a malolactic bacteria starter culture in two different gels to improve its activity and stability under stressful winemaking conditions. The two different encapsulation methods: a normal alginate gel as well as a silica-alginate gel, were also compared to a “free” version of the bacteria. The bacteria used in the trial was Lalvin VP 41 MBR from Lallemand. Bacteria was inoculated into de-alcoholised wine with adjusted concentrations of alcohol, pH, YAN and malic acid. Malolactic fermentation was also conducted at various temperatures ranging from 13 – 22°C. Results The malolactic activity of the Si-Al capsules was significantly higher than the alginate capsules and the free bacteria, in high alcohol conditions. At 16% alcohol free bacteria decreased the malic acid concentration only 1% 72 hours after inoculation. The alginate capsul