Food manufacturers often use the additive to help balance the acidity in cheese and to add tartness to frozen desserts and carbonated fruit drinks. For centuries, food makers have used it to turn cabbage into sauerkraut and milk into yogurt. You might also encounter it in beer, jellies and salad dressings. Enjoyed Spanish olives recently? You've sampled the preservative powers of lactic acid. The additive is beloved for its food safety role, too; bacteria hate acidic environments and lactic acid keeps bad bacteria from spoiling food.

Almost all living organisms produce this acid. Experts give it the green light, and there are no reports about it causing the body harm these many years we've used it. If you see lactic acid on the ingredient list, feel free to take a bite or have a sip.