木薯护色及贮藏性研究

The study on color protection and storage quality for cassava

【目的】以木薯为试验材料,研究经无硫护色剂处理后贮藏木薯的色泽变化和贮藏品质变化,以期得到鲜切木薯安全有效的护色方法.【方法】通过单因素试验研究不同浓度的L-半胱氨酸(L-Cys)、柠檬酸、维生素C、护色时间和护色温度对鲜切木薯色泽的影响,采用正交试验筛选出鲜切木薯最佳护色工艺,并测定经最佳护色工艺处理后贮藏木薯的酶活性和质量损失率变化.【结果】木薯常温护色最优条件为L-Cys含量0.8%,柠檬酸含量0.6%,VC含量0.5%,护色时间15 min.最优条件下鲜切木薯色值L^(*)值为75.75.经护色处理的鲜切木薯与未护色的木薯相比,贮藏期间苯丙氨酸解氨酶(PAL)、多酚氧化酶(PPO)和过氧化物酶(POD)活性、贮藏质量损失率均降低.【结论】无硫复合护色处理可对鲜切木薯有效的护色,并且可降低贮藏木薯的酶活性和质量损失.

【Objective】In order to obtain a safe and effective method of color protection for fresh-cut cassava,the changes of color and storage quality of stored cassava were studied with sulfur-free color protection treatments.【Method】A single-factor test was conducted to study the effects of different concentrations of L-cysteine(L-Cys),citric acid,vitamin C,color protection time and color protection temperature on the color of fresh-cut cassava.The best color protection technology of fresh-cut cassava was screened out by the cross tests,and the enzyme activity and quality loss rate changes of the stored cassava after the best color protection technology were measured.【Result】The optimum conditions for color protection of fresh-cut cassava at room temperature were as follows:0.8% L-Cys,0.6% citric acid,0.5% vitamin C,and color protection time 15 min.Under the optimum conditions,L^(*) value of fresh-cut cassava was 75.75.Compared with the control group,color protection treatment reduced the PAL,PPO,POD,and the loss rate of storage quality during storage of fresh-cut cassava.【Conclusion】The sulfur-free compound color protection treatment can effectively protect the color of fresh-cut cassava,and can reduce the enzymatic activity and quality loss of stored cassava.