Effects of storage and handling on vitamins in fresh lima beans.

Fresh Lima beans were subjected to various combinations of handling factors, including storage time and temperature, air during storage, water during preparation, hulling, and preparation method, to determine their effects on ascorbic acid, thiamin, and carotene content. Freezing resulted in highly significant losses of ascorbic acid and thiamin. Longer storage time and higher storage temperature resulted in significant reduction in ascorbic acid. Bruising, such as that occurring when beans are mechanically hulled, caused significant losses of both carotene and ascorbic acid. Significant interactions indicated that subjecting beans to circulating air and to bruising increased degradation of ascorbic acid and carotene. Increasing storage temperature compounded the effects of air circulation and of storage time on ascorbic acid. For example, 24-hr. storage at 45 degrees F was as severe as 72 hr. at 37 degrees F. Highest overall content of ascorbic acid was attained with hand-hulled samples stored in still air before cooking. Lowest content of ascorbic acid occurred in bruised beans cooked in copper-fortified water.