Effects Of Different Packaging And Inflatable Packaging At Different CO₂ Concentrations On Postharvest Quality And Resistance Physiology Of Red Fuji Apple

The objective of this work was to evaluate the effect of different packaging and different CO2 concentration inflatable packaging on the postharvest quality and resistance physiology quality of Red Fuji apple, and to explore the optimal CO2 package concentration and high CO2 damage mechanism, provide further theoretical guide for the develpment and application of CA storage technology of Red Fuji apple.1. The effect of different packaging on postharvest and shelf-life quality were different after 4 month cold storage, the double PVC bags were the best, followed by singler PVC bags and double PE bags, the single punch bags and carton were less effective. During the shelf-life, the effect of each treatments which reduce the respiration rate, ethylene respiration rate and reduce the dacrease of fruit firmness、SSC and TA, prevent the MDA content increased and mass loss were as follows: double PVC packages、single PVC packages、double PE packges、single PE packages、PVC punch packages、PE punch packages、carton. But a very few brown fruit were discovered in double PVC bags during the shelf-life.2. Using different CO2 concentrations inflatable packaging and storage at 0°C, the gas contents were balanced around 30 th day, the O2 content was between 12.3%~14.4% of each treatments, the CO2 content was in big difference, the CO2 content of 8% CO2 concentration inflatable packaging was up to 6.7%, significantly higher than 2% CO2 concentration inflatable packaging and control; In 50μm PVC inflatable packaging condition, the CO2 injury time of control、2%、5% and 8% were 60d、45d、75d、75d, and the control and 2% injury rate was the lowest at 75 th day; compared with other treatments, the injury rate of 2% inflatable package was minimum at the end of storage. Thus, 2% CO2 inflatable packaging works best, 5% and 8% CO2 inflatable packaging aggravated CO2 injury, the injury rate of 8% CO2 inflatable packaging was most serious. High concentrations of CO2 can speed the appearance of Fuji apple CO2 injury.3. Different treatments can reduce the respiration rate, maintain higher fruit firmness、SSC and TA, can better maintain fruit storage and shelf-life quality, and can prevent the mass loss. But there were big differences between different concentrations, in 50μm PVC inflatable packaging conditions, compared with other treatments, 2% CO2 inflatable packaging can reduce the respiration rate, maintain higher fruit firmness、SSC and TA, can better maintain fruit storage and shelf-life quality, can prevent the mass loss and CO2 injury, 2% CO2 inflatable packaging works best, 5% and 8% CO2 inflatable packaging reduced the preservation effect of apples.4. Red Fuji apple were sensitive to CO2, high concentration of CO2 can lead to the fruit physiological metabolic disord, skin and flesh browning. But 2% CO2 inflatable packaging can better maintain fruit antioxidant properties, reduce fresh browning in late storage, 5% and 8% CO2 may cause damage, and 8% CO2 can lead to the most serious injuries. High CO2 can lead to the increased of membrane permeability, accumulation of MDA, increased of lipid peroxidation, cause damage to the membrane system, accumulation of harmful substances such as ethanol content, increased of phenolics and PPO activity, decreased of POD, SOD and other protective activity, the contact of PPO and polyphenols made the fruit brown accentuated.