红茶发酵液菌种、发酵底物与工艺的优化研究

Optimization on the strain、fermentation substrate and process of black tea fermentation liquid

以红茶为原料,研究优化红茶发酵液的发酵工艺。通过菌种、碳源和氮源的筛选,在单因素试验的基础上,采用正交试验优化发酵原料的配比,采用响应面优化对红茶发酵液的发酵工艺进行优化。结果表明,红茶发酵液的最佳菌种为植物乳杆菌;最佳发酵底物为红茶粉料液比1∶35,碳源和氮源分别是葡萄糖和80%乳清蛋白,添加量分别为12.5%和1%;最佳发酵工艺参数为:发酵时间50 h,发酵温度35℃,植物乳杆菌接种量0.72 g/L。在此条件下,红茶发酵液中活性产物含量达到最优,其中总儿茶素和生物碱含量达到2.78 g/L和1.13 g/L,乳酸和总酸含量分别达到6.56 g/L和7.13 g/L,得到的红茶发酵液口感饱满,酸甜适中,茶香浓郁。

Using black tea as raw material,study and optimize the fermentation process of black tea fermentation liquid.Through screening of bacterial strains,carbon sources,and nitrogen sources,based on single factor experiments,orthogonal experiments were used to optimize the proportion of fermentation materials and response surface methodology was used to optimize the fermentation process.The best strain of black tea fermentation liquid was Lactobacillus plantarum;the optimal amount of raw material added were as follows:solid-liquid ratio 1:35,fermentation substrate was glucose and 80%whey protein,adding 12.5%and 1%;and the optimal fermentation process parameters were as follows:fermentation time 50 h,fermentation temperature 35℃,Lactobacillus plantarum inoculum 0.72 g/L.Under these conditions,the active products content in black tea fermentation liquid reached the optimum,including 2.78 g/L total catechins,1.13 g/L alkaloids,6.56 g/L lactic acid and 7.13 g/L total acid,the black tea fermentation liquid obtained was full in taste,moderate in sweetness and sour and rich in tea flavor.