Effects of Gamma Radiation on Certain Water-Soluble Vitamins in Raw Ground Beef

Abstract
Gamma radiation of raw ground beef (approximately 3.0 megarep) resulted in the destruction of about 10% of the riboflavin and 25% of the pyridoxine, as indicated by results obtained from microbiological and biological (rat-growth) assays. Very little, if any, of inositol, niacin or tryptophan in beef was destroyed by 3.0 megarep doses of irradiation, according to data obtained from microbiological assays. The supplementation of diets containing suboptimum amounts of pyridoxine with penicillin exerted a sparing effect on the pyridoxine requirement of rats, as was evidenced by an increased growth rate and an increased pyridoxine content of the liver. Rat liver storage of pyridoxine increased on a curvilinear basis as the level of pyridoxine was increased in the diet, with or without penicillin supplementation. Comparable assay values for pyridoxine in beef were obtained by the microbiological and rat growth assays (without penicillin supplementation). This suggests that all forms of pyridoxine in beef were equally active for the rat in these studies.