不同SO_2添加量的草莓发酵微生物种群及理化特性动态测定

Dynamic determination of microbial population and physicochemical characteristics during strawberry fermentation added various SO_2 concentration

研究了不同SO2添加量的草莓发酵醪微生物种群数量以及还原糖、滴定酸的变化。平板涂布培养法的实验结果显示,在不同SO2添加量的草莓发酵过程中,酵母菌数量先增加后稳定,细菌数量先增加后减少,霉菌数量逐渐减少直至消失,未检测出醋酸菌和乳酸菌,添加120mg/L SO2对抑制草莓发酵醪中细菌和霉菌的作用较明显。在发酵过程中,添加低质量浓度(0～120mg/L)SO2的草莓发酵醪还原糖先升后降,而添加高质量浓度SO2的草莓发酵醪还原糖质量浓度无变化;每种SO2添加量下的滴定酸质量浓度变化不明显,但滴定酸质量浓度随SO2添加量增加而降低。

The change of microbial population and reducing sugar and titratable acid in crushed strawberry fermented by Schizosaccharomyces was investigated at different level of SO2.The yeast numbers increased at first phase and then kept stable,bacterium numbers increased at first phase and then decreased,mold numbers decreased gradually until disappeared,no acetic acid bacterium and lactobacillus was detected,SO2 concentration of 120 mg/L was more effective to restrain bacterium and mold than other concentration of SO2.During strawberry fermentation,reducing sugar increased at first phase and then decreased at 0-120 mg/L SO2,but didn't change at higher SO2 concentration;titratable acid changed a little at certain SO2 concentration,but titratable acid decreased with the increase of SO2 concentration.