The exact cause of decline of the fermentation rate in blueberry
wines is not yet understood, but stuck fermentation is frequently
observed during the fermentation of blueberry wine. While it takes
approximately 7e10 days to complete alcoholic fermentation in
grape wines, it takes more than 3 weeks to the end of fermentation
in blueberry wines. In our previous study (Seo, Yoo, Park, & Son,
2014), the fermentation rate of blueberry wine decreased in proportion
to the amount of water added prior to fermentation, suggesting
that nutrient deficiency may be a cause of the fermentation
problem, especially with a shortage of assimilated nitrogen. We
then investigated the effect of various yeast nutrients on stuck and
sluggish fermentation of blueberry wine, and we accidentally
found that bananas could be used as a nutritional supplement for
yeast to solve stuck and sluggish blueberry wine fermentation.