Screening low-methanol and high-aroma produced yeasts for cider fermentation by transcriptive characterization

Area of Science:

• Enology
• Microbiology
• Food Science

Background:

• Commercial yeast strains for cider production in China currently do not meet industry development needs.
• There is a demand for improved yeast starters to enhance cider quality and diversity.

Purpose of the Study:

• To screen and evaluate various yeast strains for their suitability as starters in cider production.
• To identify optimal Saccharomyces cerevisiae strains for improved cider fermentation.

Main Methods:

• Screening of eight yeast strains including Saccharomyces cerevisiae, Schizosaccharomyces pombe, Pichia bruneiensis, and Pichia kudriavzevii.
• Assessment of growth performance, methanol production, and aroma profiles.
• Transcriptome analysis using RT-qPCR to understand gene expression related to fermentation.

Main Results:

• Saccharomyces cerevisiae strains WFC-SC-071 and WFC-SC-072 demonstrated high sugar utilization (91.6% and 88.8%) and low methanol production (<200 mg/L).
• Fermentation with these strains led to an increase in key aroma compounds, enhancing cider's characteristic aroma.
• RT-qPCR indicated upregulation of genes related to growth, carbohydrate uptake, and aroma production in the selected strains.

Conclusions:

• Saccharomyces cerevisiae strains WFC-SC-071 and WFC-SC-072 are identified as optimal starters for cider production.
• These yeast strains can contribute to cider diversification and meet varied consumer demands.
• The selection of these strains promotes the overall development of the cider industry.