Estimation of the Pantothenic Acid Content of Foods Using a Microbiological Assay and a Radioimmunoassay

Seventy-five processed and prepared foods commonly consumed in the United States were analyzed for pantothenic acid. The foods were analyzed using the traditional microbiological assay for the vitamin and using a new radioimmunoassay (RIA). The preparation of food sample extracts for both assays was modified. After the food samples underwent enzyme hydrolysis, the food-enzyme mixture was dialyzed to obtain a clear extract for use in the assays. Previously, the food-enzyme mixture was poured through filter paper for clarification. A very high correlation (r2= .937) between the results from the RIA and the microbiological assay was found. There was a statistically significant difference between the two assay results for all foods and for the subgroups meats, breads and cereals, and fruits and vegetables at p = .05. At p = .01, all foods and the subgroup of meats had significantly differences between the microbiological assay results and RIA results. Breads and cereals and fruits and vegetables did not have significantly different results between the two assay methods at p = .01. For all foods and all subgroups, the microbiological assay produced a higher mean result than the RIA. The RIA is an acceptable assay for pantothenic acid in breads and cereals and fruits and vegetables. Further study is needed to determine if the microbiological assay or the RIA provides the truest picture of the pantothenic acid content of animal tissues. Findings from the assay of 75 foods are reported, with results from both assays expressed as milligrams of pantothenic acid per 100 grams of food, milligrams of pantothenic acid per serving, and milligrams of pantothenic acid per 1,000 kilocalories of food