Accelerated Storage

Two studies were conducted to determine the relative effect of various combinations of antioxidants on vitamin A oxidation and isomerization in nonfat dry milk (NDM). In the first study, one lot of pasteurized unfortified skim milk was divided, fortified with vitamins A and D and one of 11 antioxidant treatments, and spray dried. A control batch from the same lot was also fortified with vitamins A and D and spray dried. Samples were analyzed for total vitamin A bioactivity after zero, one, and two weeks of storage. After two weeks at 50 °C, the only NDM samples that did not experience significant vitamin A loss were those treated with butylated hydroxytoluene, either alone at 0.57 ppm or at 0.29 ppm in combination with 250 ppm ascorbi