The main ingredient of the VA serum is L-ascorbic Acid.

This component reacts sensitively to oxygen, heat, and light and is easily oxidized.

Therefore, the color of the VA serum gradually turns yellow, which means it is a pure vitamin c component.

Cos De BAHA Vitamin C serum does not use synthetic ingredients or pigments that prevent color changes, and our own formula stabilizes the vitamin C oxidation process as much as possible.

So you can use it with confidence.

The oxidation process of vitamin C.

It's okay to use it.

Even if it turns Dark brown, it does not cause skin problems.

However, we recommend using vitamin C serum as soon as possible after opening.