Ever wonder why an open bag of chips gets mushy, or why day-old bread feels hard? Scientists haven't figured out the entire process of staling quite yet, but the American Chemical Society’s latest Reactions video explains the chemical processes that make these tasty snacks grow stiff or soggy. It also provides tips for storing food items for optimal freshness, and explains how to rescue them using an oven or microwave.

[h/t Reactions]

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