Abstract: In order to screen for native Oenococcus oeni with good fermentation tolerance, seven O. oeni strains isolated from the wine-producing area of the Hexi corridor of Gansu province were investigated for their tolerance to fermentation factors such as pH value, alcohol, SO2 concentration and fermentation temperature. Then, the strains with good fermentation tolerance were selected to analyze their adaptability to various combinations of pH value, alcohol content and SO2 concentration. The results showed that there were differences in fermentation tolerance among the seven strains, and that each strain had different resistance to different stress factors. Strains MG-1, MG-7, QL-11 and ZX-1 could grow and proliferate under the conditions of pH 3.2, alcohol content 14% and SO2 concentration 40 mg/L. In decreasing order of importance, the factors affecting the growth of strains MG-1, MG-7, QL-11 and ZX-1 were alcohol content, SO2 concentration and pH value, while those affecting the growth of strains QL-11and ZX-1 were alcohol content, pH value and SO2 concentration. Collectively, we demonstrate that strain ZX-1 has the strongest fermentation tolerance among the tested strains, followed by MG-1, MG-7 and QL-11, all of which have potential for industrial application.

Key words: Oenococcus oeni; fermentation conditions; tolerance