Caffeine is a white, crystalline power with the formula C8H10N4O2. It is moderately soluble in cold water, but much more soluble at higher temperatures. It is slightly soluble in ethanol. It is a purine, with two, heterocyclic rings fused together.Caffeine Powder, USP/FCC/Food Grade is for use in food applications and other consumable processes.Caffeine acts as a central nervous stimulant that can help to reduce fatigue and drowsiness and may aid in increasing levels of concentration. By blocking the A2A receptor, caffeine can increase dopamine levels, which has stimulating and mood-enhancing effects.