How to prevent fruit oxidation during fruit cutting

Fruit cutting can be prevented from oxidation by soaking in acidic solution, sealing and isolating from air, low-temperature refrigeration, reducing cutting area, and cutting and eating immediately. The oxidation of fruits is mainly due to the enzymatic browning reaction caused by the contact between polyphenol oxidase and oxygen. By intervening in the reaction conditions, the discoloration can be effectively delayed.

1. Acidic solution soaking

Soak the cut fruits in lemon juice, white vinegar, or vitamin C solution. An acidic environment can inhibit polyphenol oxidase activity. The citric acid and ascorbic acid in lemon juice have reducing properties and can block oxidative chain reactions. Apple, pear and other easily oxidizable fruits are recommended to be diluted in lemon juice at a ratio of 1:10 and soaked for 1-2 minutes.

2. Seal and isolate from air

Wrap the fruit pulp tightly with cling film or store it in a vacuum preservation box to reduce the contact area with oxygen. The plastic wrap should completely cover the cut area, and vacuum treatment can reduce the oxygen concentration to below 5%. Mango, avocado and other soft fruits are suitable for this method.

3. Low temperature refrigeration

4 ℃ refrigeration can reduce enzyme activity and delay oxidation rate. Tropical fruits such as bananas and peaches need to be sealed in plastic bags and refrigerated to avoid cold damage. The fruit slices after refrigeration should be consumed within 2 hours, as reheating will accelerate the oxidation process.

4. Reduce cutting area

Using large pieces for cutting is less prone to oxidation than slicing, and the oxidation rate of the entire fruit is the slowest when only the core or skin is removed. Watermelon is recommended to be cut into pieces to preserve some of the skin, strawberries to preserve sepals, and pineapples to preserve the crown buds to delay oxidation.

5. Principle of freshly cut and eaten

Processing fruits within 15 minutes before consumption can maximize freshness. Commercial fruit cutting products often contain food grade antioxidants such as D-isoascorbate sodium. For home production, it is recommended to prioritize fresh seasonal fruits.

It is recommended to use a combination of various anti oxidation measures when processing fruit slices in daily life, such as soaking the sliced apples in light salt water before refrigeration. Avoid using metal knives to cut acidic fruits, as stainless steel material may catalyze oxidation reactions. For fruit slices that need to be taken out, a portable ice pack can be used to maintain a low temperature environment. Special populations such as diabetes patients need to control the amount of acid solution used, and gastrointestinal sensitive people should avoid eating frozen fruit slices on an empty stomach.