haidut, you know that fresh vitamin C has a white colour, and in time its colour becomes yellow.
Does the colour change indicate that it is becoming the oxidised form (dehydroascorbic acid) that we want to ingest, or is that yellow substance something different and harmful/useless?
Can we get the same DHA by keeping the vitamin C powder's package open to accelerate the process?
Some of the vitamin C should get oxidized when exposed to air but I don't know how much. It could also be a sign of degradation by bacteria which can metabolize the vitamin C into something else.