绿茶提取物对红曲黄酒酿造特性的影响

研究了绿茶提取物(Green tea extract,GTE)对红曲黄酒酿造过程中红曲霉和酵母菌的生物量、产酶特性及其酿造特性的影响。在传统红曲黄酒酿造工艺的基础上,添加不同浓度醇提取的GTE共发酵,研究GTE对红曲霉和酵母的生长代谢产酶总量及红曲黄酒出酒率的影响。结果表明,添加2%的GTE进行共发酵,纯水提取的GTE和15%的乙醇溶液提取的GTE,其EGCG、ECG含量较低,对红曲霉和酵母菌的生长、代谢产酶均有促进作用,与对照相比红曲霉生物量分别提高2.4%和5.0%,产酶总量分别提高26.4%和47.8%,淀粉酶酶活分别提高了6.3%和11.8%;酵母菌生物量分别提高了9.4%和10.4%,产酶总量分别提高了21.2%和30.5%;出酒率分别提高了10.67和13.87百分点。75%的乙醇溶液提取的GTE,其EGCG、ECG含量较高,对红曲霉产酶和酵母菌的生长、代谢产酶有抑制作用,与对照相比出酒率降低了9.28百分点。

Effects of Green Tea Extracts on Brewing Characteristics of Hongqu Glutinous Rice Wine

The effects of green tea extracts on the biomass of monascus and yeasts, productivity of enzymes and brewing characteristics were investigated. Based on traditional fermentation technology for hongqu glutinous rice wine, green tea extracts by different ethanol solvents were added for fermentation and their effects on growth and metabolites of monascus and yeasts as well as alcohol yield were studied. The results showed that when 2%GTE was added for fermentation, green tea extracts by water or 15% ethanol-water solution resulted in relatively low EGCG and ECG. Moreover, they also exhibited promoting effects on growth of monascus, yeasts and the metabolites of enzymes. For example, the biomass of monascus increased by 2.4%and 5.0%, the productivity of enzymes increased by 26.4% and 47.8%, diastase activity increased by 6.3% and 11.8%, the biomass of yeasts increased by 9.4% and 10.4%, the productivity of enzymes increased by 21.2%and 30.5%, the enzyme activity increased by 6.3%and 11.8%, the alcohol yield increased by 10.67 and 13.87 percent point with the control. Extracts of green tea by 75%ethanol-water solution led to the highest EGCG and ECG, which exhibited negative effects on the growth of monascus and yeasts and the productivity of enzymes in monascus. The alcohol yield also decreased by 9.28 percent point.