曲酸-海藻酸钠复合膜的制备及其对百合鳞茎片褐变的抑制作用

Preparation of Kojic Acid-Sodium Alginate Film Coating and Its Effects on the Browning of Lily Bulbs

为了开发百合鳞茎片的活性包装材料,本研究利用3因素3水平L9(34)正交试验评价合适的海藻酸钠、甘油及曲酸浓度来制备复合液膜,并研究其对百合鳞茎片在4℃贮藏15 d的褐变抑制作用。结果表明,复合膜最佳配方中海藻酸钠、甘油及曲酸浓度分别为8 g/L、0.3%和1.0 g/L;同时曲酸-海藻酸钠涂膜能够抑制百合鳞茎片褐变和微生物生长,抑制百合鳞茎片多酚氧化酶(PPO)、过氧化物酶(POD)和苯丙氨酸解氨酶(PAL)的活性,且与对照组相比三种酶活性分别减少31%、21%和29%;涂膜处理能够抑制酚类和醌类增加,与对照组相比,酚类和醌类含量分别减少16%、15%。曲酸-海藻酸钠涂膜同样能够阻止百合鳞茎片硬度降低和丙二醛(MDA)含量增加。综上,曲酸-海藻酸钠涂膜能很好地抑制百合鳞茎片褐变以及保持百合鳞茎片品质。

In order to develop active packaging of lily products,L9(34)orthogonal array design(OAD)was evaluated and verified the optimum condition of the three factors(sodium alginate,glycerinum and kojic acid concentration),and the browning inhibition effect of the composite coating on the lily bulbs stored at 4 ℃ for 15 days was studied. Results showed that the best concentrations of sodium alginate(SA),glycerinum and kojic acid(KA)were 8 g/L,0.3% and 1.0 g/L. At the same time,PLA/SA composite films treatment inhibited browning degree and microbial growth. Compared with the control,polyphenol oxidase(PPO),peroxidase(POD)and phenylalnine ammonialyase(PAL)activities of KA/SA composite films treated lily bulbs were reduced by about 31%,21% and 29% after being soaked in composite membrane respectively. Total phenolic and quinone contents were decreased by 16% and 15%. KA/SA composite films treatment prevented the decrease of the firmness and the rise of MDA contents. These results indicated KA/SA composite coating could effectively inhibit the browning and maintain the quality of lily bulbs.