Effects of co-inoculation on wine-quality attributes of the high-acid, red hybrid variety chambourcin

Simultaneous fermentation with yeast and malolactic bacteria has been reported to effectively increase wine production efficiency and microbiological stability and to improve flavor characteristics. In the present study, the results of co-inoculation (i.e., simultaneous inoculation of must with yeast and bacteria) were compared with those of traditional sequential fermentation (i.e., inoculation of bacteria after completion of the primary yeast fermentation) in the vinification of wine made from the red French-American hybrid variety Chambourcin. Although production length, ranging from the inoculation of the primary fermentation through the completion of malolactic fermentation, varied between the two treatments, yeast and bacterial populations, which were monitored and enumerated throughout fermentations, showed similar survival in both treatments. Alcohol concentration after malolactic fermentation was significantly (p < 0.05) higher in co-inoculated wines; however, this difference was negligible. No other statistically significant differences in wine chemistries were observed between the two treatments. Potentially perceptible differences in sensory characteristics of the wines were evaluated with a triangle difference test (n = 92). Consistent with the chemical analyses, sensory evaluation indicated no differences in sensory profiles between the wines produced by co-inoculation or sequential inoculation. The results of this study demonstrate that co-inoculation can be used as a technique for the vinification of high-acid red grape varieties, such as Chambourcin, without altering wine quality, while improving production efficiency.