Two good alcohol yeast strains were obtained from high temperature alcohol fermentation broth of corn mash after enrichment culture,high temperature acclimation and screening. The strains had better alcohol fermentation properties at 35 ℃ than yeast strain RⅡ and active,dried alcohol yeast with high temperature tolerance.
The protoplast yeasts of h-1 and SP-48 were fused using PEG, and fusion strains LZ-3 which could tolerate high-temperture and produced higher alcohol was achieved.
By hybridization JD9-22 (α,STA, inh, ade-) of Saccharomyces diastaticus, mass spore isolation, the segregation and recombinatin of STA gene, INH1 gene and the genetic markers, meiosis Z6-10(α,STA, inh, arg- ) strain with eliminated INH1 gene was selected.
In the proceed of maize alcohol,the influence of the temperature,pH,the quantity of the yeast and the time of fermentation were determined when the temperature tolerant active dry yeast was used in the experiment. The orthogonal experiment was followed. The optimum conditions of fermentation were gained:fermentation temperature si 37℃,pH of the liquid is5.0,the quantity of the yeast is 1.2‰ and the time of fermentation is 48h.