CaCl2电解水处理提高绿豆芽品质及其机理

利用CaCl₂电解水(CaCl₂electrolyzedwater,CEW)浸泡绿豆后使其发芽，研究CEW对绿豆芽的保鲜效果及作用机制。结果表明，25 mmol/L CaCl₂浓度的电解水处理后，在贮藏5 d时，与对照组相比，其质量损失率降低，硬度和脆度约是对照组(自来水处理)的1.28倍，并且杀菌作用明显，绿豆芽表面微生物数量减少近一个对数值；低场核磁共振结果表明，绿豆芽水分状态有所改变，结合水含量增加；相对电导率、丙二醛含量和过氧化氢含量分别降低约16.5%、27.5%、36.8%，维持了细胞膜完整性，减少活性氧积累从而减轻膜脂过氧化程度。此外，CEW处理后绿豆芽贮藏期间的褐变现象得到抑制，机理与褐变底物总酚含量降低以及多酚氧化酶、过氧化物酶、苯丙氨酸解氨酶活力下降有关。由此可见，CEW处理可一定程度上延缓绿豆芽在贮藏过程中的品质劣变。

Effect and Mechanism of CaCl2 Electrolyzed Water Treatment on Improving the Quality of Mung Bean Sprouts

Mung bean seed was soaked and germinated in CaCl2 electrolyzed water (CEW) in order to investigate the effect and mechanism of CEW on preserving the quality of mung bean sprouts. The results showed that after 5 days of storage, the mass loss percentage of mung bean sprouts treated with electrolyzed CaCl2 solution at a concentration of 25 mmol/L decreased, and the hardness and brittleness increased by approximately 1.28 times higher than compared with the control group treated with tap water. The bactericidal effect of CEW was obvious, reducing the microbial load on the surface of mung bean sprouts by nearly one lg (CFU/g). Low-field nuclear magnetic resonance (NMR) spectroscopy showed that the state of water in mung bean sprouts changed, and the bound water content increased. The relative conductivity, malondialdehyde (MDA) content and hydrogen peroxide content decreased by 16.5%, 27.5%, and 36.8%, respectively, the integrity of the cell membrane was maintained, and the accumulation of reactive oxygen species (ROS) was reduced, thus reducing the degree of membrane lipid peroxidation. In addition, the browning of mung bean sprouts during storage was inhibited by CEW treatment, and the mechanism could be related to the decrease in the content of total phenols as browning substrates and the decrease in the activities of polyphenol oxidase (PPO), peroxidase (POd) and phenylalanine ammonialyase (PAL). Therefore, CEW treatment can delay the quality deterioration of mung bean sprouts during storage to a certain extent.