How to prevent oxidation of fresh cut fruits

Fresh cut fruits can delay oxidation by soaking them in acidic solutions, isolating them from air, and storing them at low temperatures. The oxidation of fruits after cutting is mainly caused by the contact between polyphenol oxidase and oxygen, and controlling enzyme activity and oxygen contact is key.

1. Acidic soaking

Soaking cut fruits in lemon juice or diluted salt water can effectively slow down oxidation. Citric acid and vitamin C have reducing properties and can inhibit polyphenol oxidase activity. Soak in a lemon water solution with a concentration of about 5% for 1-2 minutes, as prolonged soaking may affect the taste. This method is applicable to easily oxidizable fruits such as apples and pears.

2. Vacuum sealing

Use cling film to tightly wrap or store in a vacuum container to isolate oxygen. The cling film should be completely attached to the surface of the fruit pulp to avoid the presence of bubbles. Vacuum packaging can maintain the color of apple slices for more than 6 hours. Bananas, avocados, and other soft fruits are suitable for this method, but it should be noted that vacuum pressure may alter the texture.

3. refrigeration treatment

4 ℃ low temperature environment can reduce enzyme activity and delay browning rate. Cut fruits should be placed in the refrigerator as soon as possible and stored separately from uncut fruits. When refrigerating tropical fruits such as mangoes and peaches, attention should be paid to avoiding cold damage. It is recommended to store them in a fresh-keeping box and place them in the middle layer of the refrigerator.

4. Soaking in sugar water

10% concentration of sugar water can form osmotic pressure inhibition enzyme reaction. Honey water also has a similar effect and can enhance flavor. Strawberries, dragon fruit and other fruits with low sugar content are suitable for this method, and the soaking time should be controlled within 15 minutes. Patients with diabetes should use this method with caution.

5. Pre treatment inhibition

Boiling water for 30 seconds can inactivate epidermal enzymes, suitable for fruits with skin such as peaches and plums. Steam treatment for 1 minute is equally effective and can better maintain nutrition. After processing, it needs to be cooled immediately. This method will soften the texture of the fruit and is suitable for subsequent cooking use.

When storing fresh cut fruits, attention should be paid to cleaning and disinfecting the knives and containers to avoid microbial contamination. The oxidation rate of different fruits varies greatly, and apples, bananas, etc. should be treated first. Food grade antioxidants can be used for commercial purposes, and it is recommended to consume them within 2 hours for household use. Eating foods rich in vitamin E, such as yogurt and nuts, together can help reduce the damage of free radicals to nutrients. Long term storage can consider freezing, but the taste may change after thawing.