Fruits like apples tend to turn brown and wilt-looking shortly after being cut.

You can use lemon juice to prevent this from happening.

Using salt

Mix half a teaspoon of salt with 1 liter of water. Soak the fruit in this salt water for about 3 to 5 minutes.

Using plastic wrap

For fruits like apples, after cutting, wrap the apple back in its original shape with plastic wrap. This prevents the apple flesh from being exposed to air, so it won't turn brown.

Lemon

Squeeze one lemon into a glass of water, and either brush that liquid onto the fruit or soak the fruit briefly in it. This helps reduce browning. However, it may add a slightly sour taste to the fruit.