“The biggest disadvantage of a vitamin C serum is its instability. Light and air can denature the active ingredients and render them useless. For this reason, Dr. Oz recommends using topical vitamin C serums that are packaged in opaque and airtight containers. Also, be aware that products labeled with vitamin C as an ingredient may not have active vitamin C. Check the ingredient label before you buy the product.” Source
This is why at Beach Brand we chose the light-tight and air-tight packaging. We wanted our customers to know that we care about our products stability and long term safety. Our vitamin c serum is viable for up to 12 months! Almost unheard of at the the 20% percent level our serum has.