高压二氧化碳处理对鲜切荸荠褐变的影响

为了延长鲜切荸荠的贮藏周期，本文研究冷藏条件下高压二氧化碳（HPCD）处理对鲜切荸荠褐变的影响。鲜切荸荠经高压二氧化碳（1、2、4 MPa，31℃，5 min）处理后，放在4 ℃条件下冷藏8 d，测定其在贮藏期间的色泽、硬度、多酚氧化酶活性、过氧化物酶活性、苯丙氨酸解氨酶活性及多酚类物质的变化情况。结果表明，经2 MPa和4 MPa处理均可有效抑制鲜切荸荠的褐变，而2 MPa处理可更大程度地减缓硬度的降低。与对照组相比，不同压力处理均能激活多酚氧化酶、过氧化物酶，抑制苯丙氨酸解氨酶活性，延缓多酚类物质的积累。其中，经2 MPa处理组效果最佳，贮藏至第4 d，苯丙氨酸解氨酶活性和多酚含量分别较对照组低59.1%和46.1%。研究结果可为HPCD技术在抑制鲜切果蔬褐变方面的应用提供参考。

Effect of High-pressure Carbon Dioxide Processing on Fresh-cut Chinese Water Chestnut Browning

In order to prolong the storage period of fresh-cut Chinese Water Chestnut (CWC), the inhibitory effect of high-pressure carbon dioxide treatment on browning of fresh-cut CWC was studied in this paper. Fresh-cut CWC were treated with HPCD (1, 2, 4 MPa, 31 ℃, 5 min), and then storage at 4 ℃ for 8 d. The color, hardness, polyphenol oxidase (PPO) activity, peroxidase (POD) activity, phenylalanine ammonia-lyase (PAL) activity and polyphenols were measured during storage. The results showed that the browning of fresh-cut CWC can be effectively inhibited by 2 MPa and 4 MPa treatment, while the hardness reduction can be slowed down by 2 MPa treatment to a greater extent. Compared with the control group, different treatments could activate activity of PPO and POD of fresh-cut CWC, inhibit PAL activity, and inhibit the accumulation of polyphenols. Therefore, the 2 MPa treatment group had the best effect, and PAL activity and polyphenol content decreased by 59.1% and 46.1%, respectively compared with the control group on 4th day. It can provide a reference for the application of HPCD technology in inhibiting browning of fresh-cut fruits and vegetables.