Browned vitamin C ampoules are ineffective! Let's share the proper storage method.

Many people use vitamin C products for whitening, right? Pure vitamin C is sensitive to light and heat, so it quickly oxidizes and turns brown at room temperature. Products that have already turned brown are not only less effective, but can also irritate the skin. I wrap the bottle in aluminum foil immediately after purchasing it, blocking light, and always refrigerate it before use. Using it cold also helps tighten pores, so it's a win-win situation.