Anderson says ascorbic acid -- essentially just vitamin C powder -- can help save money by preserving apples, bananas, avocados, eggplant and any other produce that browns. Sprinkle on fruits or guacamole. Both will last days in the fridge if covered tightly with plastic wrap. Ascorbic acid does have a tangy, lemony taste. In some cases, you can dilute ascorbic acid, such as storing apples in a mix of ½ teaspoon in 1 cup of water. With other produce such as bananas or guacamole, either sprinkle lightly or mix it well, respectively.
"You'd have to use about six lemons to get the same amount of ascorbic acid as about 1 teaspoon of the powder," Anderson says.