... powder, no caking, no impurities, have peculiar smell of collagen. Soluble in water, free of impurities and precipitated in the ... human body, accounting for more than the body protein 30%. Collagen contains eighteen kinds of amino acids, high nutritional value, ... substances. The hydroxyproline and hydroxylysine is unique in the collagen amino acids. Collagen in cold water and large amplitude pH can be ...