Abstract:

Pulsed light irradiation treatment was applied on Saccharomyces cerevisiae (S. cerevisiae) under varying
conditions of voltage (1 000, 1 500, 2 000, 2 500, and 3 000 V) and pulse number (4, 8, 16, 32, and 48). A comparative
analysis between the variant and original strains was performed for differences in flocculation ability, diacetyl production,
physico-chemical properties of fermentation products and fermentation rate. Mutant strains 10# and 12# with good
fermentation characteristics were obtained by primary and secondary screening. Our results showed that pulsed light
irradiation did not negatively affect but maintained or even enhanced the fermentation performance of S. cerevisiae.

Key words: pulsed light, Saccharomyces cerevisiae, mutagenesis, variant strain, original strain