臭氧对鲜切莲藕酶促褐变的影响

Effects of Ozone on Enzymatic Browning of Fresh-cut Lotus Root

以鲜切莲藕为原料,通过测定褐变度、失重率、总酚含量、多酚氧化酶(PPO)和过氧化物酶(POD)活性,研究了臭氧处理对鲜切莲藕贮存过程中酶促褐变的影响。结果表明,随着贮存时间延长,鲜切莲藕褐变度和失重率呈增加趋势,臭氧处理可以极显著降低鲜切莲藕褐变度和失重率(P<0.01),且0.3 mg/L臭氧比0.6 mg/L效果好。当贮存时间由8 d延长为12 d时,样品总酚含量和PPO、POD活性开始降低,但总酚含量变化不大,PPO和POD活性下降较快。Pearson相关性分析表明,臭氧浓度与褐变度呈负相关(P=0.024);贮存时间与失重率、褐变度、总酚含量呈极显著正相关,与PPO活性呈极显著负相关(P<0.01)。鲜切莲藕用0.3 mg/L臭氧水处理12 min后,可以在0~4℃冰箱贮存8 d。

The effects of ozone on the enzymatic browing of fresh-cut lotus root were studied by the detections of browning degree, weightlessness rate, the content of total phenols and the activities of polyphenol oxidase(PPO) and peroxidase(POD). The results showed that, with the storage time increasing, browning degree and weightlessness rate of fresh-cut lotus root increasing. After treatment with ozone, browning degree and weightlessness rate significantly decreased(P<0.01), and the0.3 mg/L of ozone was better than 0.6 mg/L. When the storage time was from 8 d to 12 d, the content of total phenols and the activities of PPO and POD were to decrease. But the change in total phenols content was less than the activities of PPO and POD. It was also founded by Pearson correlation analysis that ozone concentration was negatively correlated with browning degree(P=0.024). At the same time, storage time was positively correlated with browning degree, weightlessness rate and the content of total phenols, and negatively correlated with the activities of PPO(P<0.01). Therefore, fresh-cut lotus root exposed to 0.3 mg/L ozone 12 min could be stored at 0~4 ℃ for 8 d.