Effects of modified atmosphere vacuum cooling (MAVC) on the quality of three different leafy cabbages

A Chinese and Patent Cooperation Treaty (PCT) invention patented process defined as modified atmosphere vacuum cooling (MAVC) was developed in the current study. In traditional vacuum cooling (VC), air enters the vacuum chamber during pressure recovery stage at the end of the cooling process. In this study, instead of air, a gas mixture consisting of 7% O-2, 7% CO2 and 86% N-2 enters the chamber to achieve modified atmosphere storage. Three types of cabbages with different morphological structure, including flowering cabbage, Chinese cabbage and green cabbage were treated by MAVC and stored for 21 d under 4 +/- 0.5 degrees C, relative humidity was controlled in the range of 90%-95%. The changes of color, sensory score, ascorbic acid, chlorophyll, respiration rate, peroxidase (POD) and catalase (CAT) activity were measured throughout the storage period. The results showed that MAVC achieved the maximum values of color, sensory score, ascorbic acid, chlorophyll and CAT, and reduced the rate of respiration and the activity of POD during storage. A comparative analysis on the three cabbages found that different leaf morphology characteristics were not the main factor affecting gas retention during MAVC, and the intercellular spaces of leaves might have greater impact on the maintaining the quality of the cabbages.