Salt water beats lemon juice for apples.

Salt water is the best lemon-free way to keep cut apples from browning in a lunch box.

The trick is simple: dissolve about ¼ teaspoon of salt in a cup of water, soak the apple slices for five minutes, then drain them and pack. That’s it. They stay white for hours and you won’t taste the salt. I’ve tried it, and it works surprisingly well.

Why? The salt interrupts the enzyme reaction that turns cut apples brown. It’s the same reason saltwater keeps some other fruit from oxidizing, but apple slices pick up very little actual salt in a short soak.

If you’re not into salt, a quick dip in honey water (two tablespoons honey in a cup of water) also works, and so does pineapple or orange juice. Commercial ascorbic acid powders like Fruit Fresh are the same idea. But the salt soak is the one that doesn’t change the flavor, and you probably already have salt.

Airtight containers slow things down a little, but they won’t save you. The soak is what does the job.

Pack the apples, not the science experiment.