No More Brown Apple Slices

Move over lemon juice. There's a new sheriff in town, and it's cracking down on bad apples.

Apple slices - a trademark of school lunches everywhere - typically turn brown and soft in just a few hours.

But it doesn't have to be that way. Scientists have developed a preservative dip-coating for apples. It is invisible and tasteless and it keeps refrigerated apple slices crunchy and delicious for up to 28 days.

The USDA's Agricultural Research Service developed the vitamin and mineral based dip, which goes by the trade name "NatureSeal."

Lemon juice is the home-made weapon of choice for fighting apple browning, but it can make the apple taste tangy and can change its color and texture. Not only does it alter taste, but lemon juice doesn't provide long term results.

"NatureSeal" neither affects the taste or color of the apple, and lasts much longer than lemon juice in a fridge, says co-creator Dominic Wong.

In light colored fruits - like apples, pears, and peaches - enzymes interact with the air and cause oxidative browning. Browning generally results in the loss of vitamin C and ascorbic acid. By adding lemon juice, which contains lots ascorbic acid and vitamin C, this reaction can be slowed. "NatureSeal" has found a way to slow this process even more.

"NatureSeal" was developed after extensive testing by the USDA and received a patent in 1999. Since then, "NatureSeal" carved its way into the cafeteria world, as well as in supermarket fruit salads.

Bjorn Carey

Credit: Brian Prechtel, USDA