Preservative Effects of Vacuum Packaging Combined with Cold Storage on Fresh-cut Taro

Abstract

The cut surface of fresh-cut taro tends to yellowing and browning even stored at low temperatures, leading to a decrease in commercial values. In this study, to confirm the preservative effects of vacuum packaging (VP) combined with cold storage on fresh-cut taro, the effects of VP treatment on the browning and total microbial counts in fresh-cut taro during cold storage were studied. The results showed that VP treatment delayed the decrease of L* values and the increase of a*, b*, color differences (△E), and browning index (BI) values, indicating that VP treatment significantly prevented the browning of fresh-cut taro during cold storage. Furthermore, VP treatment effectively restrained the growth and reproduction of microbials, reducing the total number of bacteria by 94.31% and the total number of yeast by 65.02% at 12 d, suggesting that VP combined with cold storage had a good preservative effect on fresh-cut taro. VP treatment led to decreased PAL and PPO activities, as well as reduced levels of total phenolics, total flavonoids, and total soluble quinones, suggesting that VP treatment hindered the browning by reducing the biosynthesis and oxidation of phenolic compounds of fresh-cut taro. Moreover, VP treatment restrained the decline in CAT activity, increased POD activity at early storage, and reduced LOX activity, H2O2 contents and MDA contents, suggesting that VP treatment alleviated cutting-induced oxidative damages by maintaining the antioxidant activity of fresh-cut taro, thus restraining the quality deterioration during cold storage. This study demonstrates that VP treatment combined with cold storage is a physical preservative technology with good preservation effects, simple and easy to use, laying a foundation for the application of VP method in the preservation of fresh-cut taro.

Keywords

• fresh-cut taro
• vacuum package
• cold storage
• browning
• pathogenic microbes