鲜切莲藕防褐变剂配方优化及保鲜效果研究

Formula optimization of anti-browning agent for fresh cut lotus root

为了得到鲜切莲藕最佳的复合防褐变剂配方,以柠檬酸、抗坏血酸、天冬氨酸质量分数为因素,褐变度为响应值,通过响应面优化鲜切莲藕复合防褐变剂配方,在此基础上将处理后的鲜切莲藕置于冰箱中冷藏,研究优化防褐变剂对鲜切莲藕品质的影响。结果表明,各因素对响应值的显著性表现为:无水柠檬酸>抗坏血酸钙>L-天门冬氨酸,最佳防褐变剂配方为:1.0%无水柠檬酸+0.1%抗坏血酸钙+0.2%L-天门冬氨酸。与对照相比,优化防褐变剂处理可显著减少维生素C的损失并延缓还原糖的生成,抑制鲜切莲藕褐变,抑制呼吸强度和乙烯生成速率,对莲藕相对电导率和丙二醛含量也具有较好的抑制效果,抑制褐变底物总酚含量的消耗和褐变相关酶活性上升。因此,优化防褐变剂(1.0%无水柠檬酸+0.1%抗坏血酸钙+0.2%L-天门冬氨酸)结合冷藏可较好地延缓褐变发生,延长贮藏时间达4 d。

In order to obtain the optimum compound of anti-browning agent formula for fresh-cut lotus root,the formulation of anti-browning agent was optimized by response surface using the quality fraction of citric acid,ascorbic acid and aspartic acid as the factor,and the browning degree was taken as the response value.Then the treated fresh-cut lotus root was stored in the refrigerator,and the effect of optimized anti-browning agent on the quality of fresh-cut lotus root was explored.The results showed that the significance of each factor to the response value was as follows:anhydrous citric acid>calcium ascorbate>L-aspartic acid.The optimal extraction conditions for browning degree were 1.0%anhydrous citric acid+0.1%calcium ascorbate+0.2%L-aspartic acid.Compared with control group,the optimized anti-browning agent browning treatment could significantly reduce the loss of V_(C) and slow down the production of reducing sugars.It could also inhibit the browning of fresh-cut lotus roots,respiration intensity and ethylene production rate,and affect the relative conductivity and malondialdehyde content of lotus roots.The consumption of total phenolic content of browning substrate was inhibited and the polyphenol oxidase(PPO)and peroxidase(POD)activities of browning-related enzymes was increased.Therefore,the optimized anti-browning agent(1.0%anhydrous citric acid+0.1%calcium ascorbate+0.2%L-aspartic acid)combined with cold storage can delay the occurrence of browning and prolong the storage time to 4 d.