The Effect of Mustard Essential Oil Combined 1-Methylcyclopropene Preservation Treatment on the Quality of Broccoli during Refrigerated Storage

The experiment took the broccoli (Brassica oleracea var. italica) as the research object, 1-methylcyclopropene (1-MCP), mustard essential oil (MEO) and 1-MCP combined MEO (1-MCP+MEO) were used to treat fresh green broccoli. The effects of physiological and biochemical indexes such as sensory quality, relative conductivity, chlorophyll, vitamin C and malondialdehyde (MDA) content on the quality of broccoli were investigated during storage. The result showed that with the increase of storage time, all groups of preservative treatments could effectively maintain the quality of broccoli during storage, among which 1-MCP+MEO treatment had the best storage effect on broccoli, effectively maintained the appearance of broccoli, avoided yellows and mildew, and slowed down the chlorophyll content and vitamin C degradation rate and made the chlorophyll content of broccoli always higher than that of other treatment groups. 1-MCP+MEO inhibited the increase of relative conductivity and MDA content in broccoli. On the 28th day of storage, the relative conductivity and MDA of the combined treatment group were 14.94% and 9.1 μmol/g, respectively, which were 43.1% and 27.6% lower than that of the control group respectively, and there was a significant difference (P<0.05), so that the cell integrity of the broccoli was maintained and the senescence of the broccoli was inhibited. After 28 days of storage, 1-MCP+MEO treatment group could effectively reduce the decrease of total phenol and total flavonoid contents, and combined treatment was 51.9% higher than that of control group, and total flavonoid content was 38.4% higher than that of control group. In addition, the activity of polyphenoloxidase (PPO) and peroxidase (POD) related to enzymatic browning was significantly inhibited, and the activity of PPO and POD were 23.6% and 48.1% lower than that of control group, respectively. Significantly lowered than control group (P<0.05). This study aims to provide a theoretical basis for the development of broccoli preservation technology and a new idea for the research and development of preservatives.