If you have ever cut and apple and left it exposed to air for a period of time you would have noticed that the flesh turns from a healthy green to a brown color. Although this doesn’t look very appealing it doesn’t affect the taste or flavor of the apple and it is still perfectly safe to eat. If you have ever wanted to know why apples turn brown, and how you can stop it from occurring, keep reading to find out.
Why do apples turn brown?
When an apple is cut the cells are damaged and oxygen is able to enter into them. These cells contain thousands of enzymes which help the cell to survive and complete its function. One of these enzymes, called polyphenol oxidase or tyrosinase, reacts with the oxygen and other compounds in the apple, called phenols. These phenolic compounds contain iron and the oxidation reaction causes the brown color, which is a kind of rust on the surface of the apple.
Ways to prevent an apple turning brown
The basic idea in preventing this problem is to inactive the enzyme or to add preservatives. Some ways to inactivate the enzyme include; cooking, adding lemon or pineapple juice, coating the fruit in sugar or syrup, and sealing or vacuum packing the apple.
Preservative chemicals, such as sulfur dioxide, are not commonly used in the home kitchen. However, they are can be very important to commercial producers of cut apple products.
Did you know?
Apples are not the only fruit or vegetable that turns brown after it is cut. Other products that suffer the same fate are potatoes, pears, bananas and peaches.
If an apple is cut with cutlery that contains rust the browning process will occur much faster!