Abstract:The content of ethyl lactate in Chi-flavor Baijiu is easily affected by the factor of production season. The content of ethyl lactate in summer is low. The bran koji was prepared by different strains of Rhizopus oryzae, Rhizopus chinonsis and Monascus, which were added to the main fermentation of Chi-flavor Baijiu. It was found that the content of ethyl lactate in crude liquor was increased using bran koji made by Rhizopus oryzae RO2 strain. Through single factor test of water content of bran koji, amount of lipase inducer, incubate temperature ,incubate time, and orthogonal test of four factors and three levels, the optimized production process of bran koji was determined as follows: the strain was RO2, the moisture content of bran koji was 60%, 0.25% soybean oil was added and cultured at 33 ℃ for 48 h. The main fermentation pilot scale test of Chi-flavor Baijiu was added dry bran koji 2%, the ethyl lactate content of crude liquor increased 2.88 times than that of blank sample (0.08 g/L), reaching 0.31 g/L. The research results effectively solved the problems of low content of ethyl lactate in Chi-flavor Baijiu, improved the aroma of the liquor and the fullness of the liquor body, stabilized the product quality, and laid a technical foundation for upgrading the Chi-flavor Baijiu.
