Sequential fermentation with indigenous non-Saccharomyces yeasts and Saccharomyces cerevisiae for flavor and quality enhancement of Longyan dry white wine

In this study, we investigated the effect of the sequential fermentation of four selected indigenous non-Saccharomyces yeasts (Candida stellimalicola HL-S-5, Rhodotorula mucilaginosa HL-S-8, Hanseniaspora uvarum HL-S-9, and Pichia kluyveri XL-48-6) and Saccharomyces cerevisiae VL2 on the oenological parameters, volatile compositions, organic acids, and sensory characteristics of Longyan dry white wine. Results showed that the ethanol concentration of pure fermentation (11.12 ± 0.04%, v/v) was the highest among all fermentations. Furthermore, the aroma concentrations produced by the fermentation of R. mucilaginosa HL-S-8/VL2 (9929.35 ± 96.87 μg/L) and P. kluyveri XL-48-6/VL2 (9017.67 ± 85.91 μg/L) were significantly higher than that of VL2 (7654.64 ± 397.07 μg/L). In particular, the treatment of R. mucilaginosa HL-S-8/VL2 increased the content of acetic esters (512.11 ± 12.92 μg/L) and fatty acid ethyl esters (6893.64 ± 56.67 μg/L), which enhanced fruity and floral characteristics. The sequential fermentation of R. mucilaginosa HL-S-8/VL2 led to significantly higher organic acid content (3843.32 ± 73.93 mg/L) than the other samples. Moreover, the sequential fermentation of R. mucilaginosa HL-S-8/VL2 wine samples resulted in the highest scores in sensory evaluation. Therefore, the sequential fermentation of R. mucilaginosa HL-S-8/VL2 was an effective way to improve wine flavor and quality. This work will provide a useful reference for improving the flavor and quality of Longyan wine through non-Saccharomyces cerevisiae.