Combined influence of lactic acid bacteria starter and final pH on the induction of malolactic fermentation and quality of cherry wines

The appropriate choice of lactic acid bacteria starter in malolactic fermentation (MLF) and a reasonable amount of acidity are two important factors that can greatly influence cherry wine's physical, biochemical and the sensory properties. The current work investigated the effect of two bacterial starters (L. plantarum CX19 and O. oeni PN4 (TM)), three pH values (3.2, 3.5 and 3.8) after alcoholic fermentation, and the interactive effects, on the MLF performance and the properties of cherry wine. The resulting MLF performance showed that PN4 had greater resistance to the lowest pH value (pH 3.2), whereas under mild wine conditions (pH >= 3.5), CX19 promoted MLF more efficiently. In both bacteria cultured cherry wines, a lower wine pH resulted in an evident reduction in colour intensity as well as a slight increase in the total biogenic amine concentration. During sensory evaluation, increased organoleptic properties associated with a higher perception of 'fruity' and a stronger palate of bitterness and astringency were evident in the wine made with CX19 at pH 3.5. Principal component analysis revealed a strong correlation between wine clustering and the chemical components, highlighting the greater significance of pH treatment.