The bright-colored skins of apples and oranges add to their appeal and protect the fruit. Once the skin is broken, browning develops and the fruits lose their luster. Browning is a reaction between enzymes in the fruit and oxygen in the air. A cool water bath keeps oxygen at bay for a few short hours; acid keeps apples and pears free of browning for up to three days in the fridge.
Vitamin C Dip
Vitamin C, or ascorbic acid, is more attractive to oxygen than fruit enzymes. Cut apples and pears dipped in vitamin C remain free of browning until the majority of the ascorbic acid is absorbed by the reaction with oxygen. Once the acid is depleted, browning starts. To prepare a vitamin C dip, mix a quart of water with three crushed 500 mg. vitamin C capsules; dip the cut apples and pears in the solution before storing in a sealed container in the refrigerator.
Citric Acid Spray
Citric acid can temporarily reduce the reaction of fruit enzymes and oxygen. Lemon juice contains high amounts of citric acid and, when, poured into a spray bottle, keeps cut apples and pears free from browning when sprayed on full-strength. A lemon juice bath is an alternative to sprays. Combine 1 cup of lemon juice with 1 cup of water and dip the cut fruit prior to storage.
When mixed with salt, acetic acid, or vinegar, reduces browning in cut apple and pear slices. Mix 2 tablespoons each of vinegar and salt with one gallon of water and dip the cut fruit slices in the mixture for 20 minutes to fend off browning. The only downside is that the apples and pears absorb the vinegar and salt, which affects the taste of the fruits. Rinsing prior to eating helps, but an aftertaste may linger.
Mixing It Up
It's possible to keep your cut apples and pears from browning by mixing them together with cut-up citrus fruits. A fruit salad containing apples, pears and acidic fruits such as oranges and pineapples reduces browning and makes for an appealing fruit snack. Store the fruit salad in a tightly sealed storage container inside the refrigerator in between servings.