Abstract
Speeding up grape must fermentation would be of great economic benefit. We subjected Saccharomyces cerevisiae VIN13 and two recombinant VIN13-strains expressing ATF1 alleles under two different promoters (either PGK1 or HXT7) to four styles of grape must fermentations; we then assessed the effect of constantly stirring a must fermentation (isomixing). The four different fermentation setups were as follows: isomixed, closed in an ANKOM Rf Gas productions system; isomixed, open in a stirred tall tube cylinder; static, closed constituting a conventional fermentation in a wine bottle equipped with an airlock and static; and static, open in a tall tube cylinder (without stirring). We report on major fermentation parameters and the volatile aroma compositions generated in the finished wines. The primary fermentations of the strains subjected to constant stirring finished after 7 days, whereas the static fermentations reached dryness after 19 days. The wines derived from isomixed fermentations produced approximately 0.7% less ethanol compared to the unstirred fermentations. The speed that the isomixed fermentation took to reach completion may provide an alternative to static fermentations in the preparation of base wines for sparkling wine production. The observed increase of volatiles of isomixed fermentations merits further investigation.
Highlights
In wine research, microvinifications are important tools employed by researchers to investigate all aspect of enology
Genetic modifications were performed on a widely-used commercial Saccharomyces cerevisiae wine yeast strain, VIN13 in this study
The native ATF1 gene was placed under the transcriptional control of the strong constitutive promoter of the PGK1 gene
Summary
Microvinifications are important tools employed by researchers to investigate all aspect of enology. The overwhelming majority of microvinifications are performed either in Erlenmeyer flasks or in wine bottles fitted with airlocks This occurs with respect to higher throughput in fermentations. A crucial aspect of wine fermentations is to determine when the so-called primary fermentation is finished and has reached dryness, i.e., when the fermentable sugars have been completely consumed. This requires roughly 1–3 weeks of fermentation, but if problems arise, prolonged fermentations can take more than twice that, or never reach dryness [1]. Providing methods to speed up fermentations or address problematic fermentations up fermentations or address problematic compromising on the quality of without compromising on the quality of the fermentations product wouldwithout be of great economic benefit.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
