乙醇喷涂处理对年糕微生物及理化品质的影响
Effects of ethanol spraying on microorganisms and physicochemical quality of rice pastry
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摘要: 为了探讨不同质量分数乙醇喷涂处理年糕对保鲜效果及腐败菌的影响,对经乙醇喷涂处理后的年糕定期测定水分含量、硬度、p H和色泽,以此评价品质变化,同时采用16S r DNA基因序列分析法鉴定年糕腐败菌。结果表明,与对照相比乙醇组处理均能显著(p<0.05)抑制年糕硬度的上升和色泽褐变、有效减少年糕水分的散失以及延缓p H的下降;乙醇组菌落总数和霉菌总数均显著低于对照组(p<0.01),且随着乙醇质量分数的增加,抑菌效果更好;年糕的优势腐败菌从初期的巨大芽孢杆菌(Bacillus megaterium)31.5%和枯草芽孢杆菌(Bacillus subtilis)32.3%,逐渐转变为枯草芽孢杆菌(Bacillus subtilis)63.2%。结果表明,乙醇喷涂处理在年糕保鲜中具有较好的抑菌作用,能延长年糕的货架期,在年糕保鲜中具有很好的应用前景。Abstract: In order to explore the effect of freshness preservation and spoilage bacteria by spraying ethanol with different mass fractions on rice pastry, this study evaluated quality changes of rice pastry sprayed on ethanol through regular tests of water content, hardness, p H and color.Meanwhile, the rice pastry sprouting bacteria were tested by adopting 16 S r DNA gene sequence analysis.The results showed that compared with the control group, the ethanol treatment groups could significantly suppress the increase of hardness and the browning of rice pastry ( p < 0.05) and effectively reduce the water loss and delay the decrease of p H value.The total counts of bacteria and molds in the ethanol group were significantly lower than those in the control group ( p < 0.01) . With the increase of ethanol content, the antibacterial effect was better. The dominant spoilage bacteria on rice pastry shifted from initially Bacillus megaterium 31.5% and Bacillus subtilis 32.3% to Bacillus subtilis 63.2%. Conclusion:Ethanol spraying had a good antibacterial effect on rice pastry freshness preservation and could extend the shelf-life on rice pastry, which had a practical application on rice pastry freshness preservation.