Apparent vitamin C in foods

Abstract

The term "apparent vit. C" provisionally refers to a group of substances occurring in foods, having no antiscorbutic activity but closely resembling ascorbic acid and reacting in the dye titration; among them are reductone, reductic acid, dihydroxymaleic acid and hy-droxytetronic acid; they have the dienol group producing enol-keto tautomerism. They are produced by the action of heat on certain carbohydrate food constituents and occur in germinated grains, malt extract, cocoa, chocolate, dehydrated fruits and vegetables, beer, walnuts, parsley, sorrel, unripe walnuts, beet and cane molasses and fruit juices and dried foods stored for several yrs. under normal conditions. The amts. in processed and dehydrated foods may gradually increase during normal storage, thus obscuring loss of true vit. C.