Prevention of enzymatic browning of Chinese yam (Dioscorea spp.) using electrolyzed oxidizing water.
In this study, the effects of electrolyzed oxidizing water (EOW) on the prevention of enzymatic browning of fresh-cut "Jiu Jinhuang" Chinese yam were investigated. The yams were immersed in the inhibitors for 25 min at 20 °C. Compared with the tap water (TW) treatment, the chromatic attributes were significantly different after 72 h of storage (P < 0.05). The activities of polyphenol oxidase (PPO, EC 1.10.3.1), peroxidase (POD, EC 1.11.1.7), and L -phenylalanine ammonia lyase (PAL, EC 4.3.1.5) were inhibited when measured at 24 h. The contents of phenolic acids, including gallic and chlorogenic acid, in the group treated with the slightly acidic electrolyzed water (SAEW) were higher than those treated with TW and neutral electrolyzed water (NEW). The group treated with NEW had the highest total phenol content (P < 0.05, at 24 h), while the group treated with SAEW had the highest flavonoid content (P < 0.05) during storage. Without being treated with inhibitors, the Km and Vmax values of yam PPO were 0.0044 mol/L and 0.02627 U/min, respectively, and the Ki of samples treated with SAEW and citric acid (CA) were 15.6607 and 2.3969 μmol/L, respectively. These results indicate that EOW is beneficial as a browning inhibitor.
College of Mechanical and Electronic Engineering, Shandong Agricultural Univ, Tai'an 271018, China; Shandong Provincial Key Laboratory of Horticultural Machineries and Equipment, Tai'an 271018, China.
Guo-Liang
GL
Jia
Jing-Ying
JY
Shi
Zhan-Hua
ZH
Song
Fa-De
FD
Li
D004156:Catechol Oxidase / Q000037:antagonists & inhibitors; D002726:Chlorogenic Acid / Q000032:analysis; D003116:Color; D027742:Dioscorea / Q000201:enzymology; D004572:Electrolysis; D004791:Enzyme Inhibitors; D005419:Flavonoids / Q000032:analysis*; D005511:Food Handling / Q000379:methods; D005519:Food Preservation / Q000379:methods*; D006801:Humans; D010084:Oxidation-Reduction; D009195:Peroxidase / Q000037:antagonists & inhibitors; D010636:Phenols / Q000032:analysis*; D010650:Phenylalanine Ammonia-Lyase / Q000037:antagonists & inhibitors; D035281:Plant Tubers / Q000201:enzymology; D014867:Water
D004791:Enzyme Inhibitors; D005419:Flavonoids; D010636:Phenols; D014867:Water; D002726:Chlorogenic Acid; D004156:Catechol Oxidase; D009195:Peroxidase; D010650:Phenylalanine Ammonia-Lyase
Chinese yam; EOW; PPO kinetics; enzymatic browning; phenolic acids