How should peaches be stored to extend their fresh, crisp period?

Prompt pre-cooling to prevent softening. Because the temperature is relatively high when peaches are harvested, especially for mid- and late-season varieties, if they are not pre-cooled promptly, the peaches will quickly soften, age, rot, and deteriorate. Therefore, after harvest, peaches should be pre-cooled to below 4°C as soon as possible. Generally, two pre-cooling methods are used: forced-air cooling and water cooling. Water cooling is fast: a peach with a diameter of 7.6 cm cooled in 1.6°C water for 30 minutes can have its temperature lowered from 32°C to 4°C. After water cooling, let the fruit dry before packing. Air cooling is slower and generally requires 8-12 hours or longer.

Antiseptic treatment before storage. For peaches that need to be transported and processed, antiseptic treatment should be carried out before storage. Secondary butylamine series preservative and freshness-retaining agents can be used to kill Penicillium and Trichoderma viride. Commonly used are clotrimazole 15-fold solution (fruit washing), and for each kilogram of peaches, a mixed solution of 100-200 mg benomyl and 450-900 mg dichloronitroaniline (fruit dipping). When washing or dipping fruit, use clean water to prepare the solution. After dipping, wait for the moisture on the fruit surface to evaporate before packing.

Choose a suitable storage method. First, cold storage. The suitable temperature is 0°C, and the suitable relative humidity is 90%-95%. Under these storage conditions, peaches can be stored for 3-4 weeks or longer. Second, controlled atmosphere storage. At 0°C and 2% oxygen + 5% carbon dioxide, peaches can be stored for 6-8 weeks or longer, and low-temperature injury can be reduced. If bricks or fluorite soaked in saturated potassium permanganate solution are added to controlled atmosphere tents or bags, the effect is even better. Third, low temperature combined with simple controlled atmosphere and antiseptic measures: after harvest, peaches at 80%-90% maturity are individually wrapped in paper and packed into cartons or bamboo baskets lined with non-toxic polyvinyl chloride film bags or polyethylene film bags, or packed directly into the above bags without paper wrapping, and immediately pre-cooled. After the fruit temperature drops, add a certain amount of secondary butylamine fumigant, ethylene absorbent, and carbon dioxide remover into the bag, tie the bag opening tightly, seal the box, and stack. Keep the storage temperature at 0-2°C to basically maintain the original firmness and flavor.

Environmental control during storage. The suitable temperature for storing peaches is 0-3°C; for mid- and early-season varieties, the temperature should be slightly higher. To prevent cold injury, use facilities with high temperature-control precision or intermittent warming cold storage, that is, store the fruit first at 0°C for 1-4 weeks, then raise the temperature to 18-20°C for 2 days, then lower the temperature to 0°C for storage. When storing peaches, the suitable oxygen concentration is 1%-3%; the carbon dioxide concentration is 4%-5%. When storing peaches in small packaging bags, the carbon dioxide concentration should be lower than 8%, and oxygen 5%-14%. After entering storage, check regularly: for short-term storage, observe the peaches once a day; for medium- and long-term storage, check once every 3-5 days.