Optimizing yeast strain selection for mulberry wine fermentation: a performance-based approach

Abstract

This study focused on identifying the optimal yeast strain for Dechang mulberry wine fermentation blended through a multi-stage evaluation process using five commercial yeasts. Initially, the Durham tube fermentation method and weight-based analysis were employed for initial screening. Subsequently, a secondary evaluation involving physical, chemical, and sensory assessments was conducted. The final stage assessed yeast tolerance to ethanol and sulfur dioxide (SO2), and the wine’s volatile compounds were analyzed using gas chromatography-mass spectrometry. The L13 yeast strain emerged as superior, demonstrating efficient fermentation initiation, rapid primary fermentation, and production of a desirable wine profile, including optimal sugar, acid, and alcohol levels. Notably, the L13 yeast strain showed resilience, tolerating up to 11% ethanol and 170-mg/L SO2 within 7 days, and contributed to a rich aromatic profile with 23 volatile compounds, including 13 esters. These attributes render the L13 strain particularly suitable for producing mulberry wine with robust fermentation characteristics and a complex aroma, enhancing both quality and sensory appeal of the final product.