How to prevent oxidation of fruits

The main methods to prevent oxidation of fruits include low-temperature refrigeration, air isolation, acidic soaking, reducing mechanical damage, and using antioxidants.

1. Low temperature refrigeration

Low temperature environment can significantly slow down the oxidation rate of fruits. Place the cut fruits in the refrigerator's cold storage layer and control the temperature at around 4 degrees Celsius to inhibit the activity of polyphenol oxidase. The color retention time of easily oxidizable fruits such as apples and pears can be extended for several hours after refrigeration. Note that tropical fruits such as bananas should not be refrigerated, otherwise they may suffer from cold damage.

2. Air isolation

Wrap the cut surface tightly with cling film or soak it in clean water to effectively block oxygen contact. Vacuum packaging can keep apple slices in their original color for more than 12 hours. The protective layer formed by soaking lemon juice can also reduce oxygen permeation, but it may alter the original flavor of the fruit.

3. Acidic soaking

Vitamin C solution or lemon juice soaking can lower the pH value and inhibit oxidase activity. Adding 500ml of water to half a lemon juice can have an effect, suitable for apples, avocados, etc. Pineapple juice contains bromelain, which may affect the texture of the fruit. It is recommended to soak for no more than 10 minutes.

4. Reduce mechanical damage

Cutting with sharp knives can reduce cell damage and lower the rate of oxidation reactions. Avoid squeezing or repeatedly flipping fruits, as the damaged area will accelerate browning. Soft fruits such as mangoes and peaches are recommended to be processed immediately after peeling, and the incision should be kept flat and smooth.

5. Soaking in food grade calcium ascorbate solution with antioxidant

can effectively protect the color, with a concentration controlled below 0.5%. The sugar film formed by honey water has antioxidant properties and is suitable for processing banana slices. Commercial preservatives should be checked for natural antioxidants and avoid chemical additives such as sulfites.

When processing fruits in daily life, physical isolation should be prioritized to minimize the use of chemical additives. Different fruits have different oxidation characteristics, and varieties with high phenolic content such as apples and bananas require special protection. Cut fruits are recommended to be consumed within 2 hours and should not be stored in refrigeration for more than 24 hours. Eating citrus fruits rich in vitamin C together can delay oxidation and enhance nutritional value. Long term storage can choose quick freezing treatment, but the taste may change after thawing.