Study On The Metabolic Characteristic Of Physiological And Biochemical In Fresh-cut Carrot

Fresh-cut fruits and vegetables are the ready-to-eat products that processed by washing, peeling, cutting or slicing, trimming, grading and packaging. Fresh-cut fruits and vegetables satisfied the demand of modern life with the advantages of natural, fresh, health and convenience. However, fresh-cut fruits and vegetables undergo substantial mechanical injuries caused by the minimal processing. These physical damages can lead to undesired metabolic changes, which shorten the shelf-life seriously. In this paper, carrot was used, and the metabolic characteristic of physiological and biochemical on fresh-cut carrot was studied. The results indicated as below:1. The carrots were cutted to cubes of 1×1×1cm~3, and were used to study the physio-biochemical changes and quality at different storage temperature. The results indicated that the maximum activities of respiration rate, POD, PAL, CAT changed greatly at 18℃, and significantly higher than that at 4℃and 10℃. Compared with 18℃, 4℃and 10℃effectively slowed down the respiration rate and the biosynthesis of phenol, suppressed the activity of enzyme that related to metabolism. Moreover, the storage condition lower temperature was more effectively.2. The carrots were cutted to cubes of 1.5×1.5×1.5cm~3, the surface layer flesh (cut 5mm from surface of the cube) and inner layer flesh (rest part of cutting site) were divided. The changes of total phenolic, MDA content, and activities of respiration rate, PPO, POD, PAL, CAT were studied. The results showed that cutting damage induced a series of negative effects. The effect on the surface layer flesh was more visible for direct hurt.3. The hot water treatment (25℃and 50℃) before processing had significant impact on physio-biochemical changes and product quality of fresh-cut carrot. The activities of respiration rate, PPO, POD, PAL, CAT were inhibited, the contents of total phenolic, soluble protein and MDA were reduced. However, the effect of 50℃hot water treatment was significant.4. 1-MCP, inhibitor ethylene binding, was used to determine the physio-biochemical changes on fresh-cut carrot. At 10℃, with the treatment of 1.0μL/L 1-MCP, the respiration rate was decreased, the contents of total phenolic and MDA reduced, and the activities of PPO, POD, PAL, CAT of the fresh-cut carrot were all inhibited. Morever, it delayed maximum peak of MDA, POD, CAT, prolonged the shelf life of fresh-cut carrot.