抄録
A large part of niacin in mature cereal grains in present in bound form which is unavailable to human body. Changes in free and bound forms of niacin during cooking of white milled rice or brown rice and during processing of wheat flour were investigated.
Both cooking and processing converted the bound niacin in the grains into available form. However, some bound niacin still remained in the products.
From these results, it was suggested that the bound niacin had two types, i. e., one was chemically bounded niacin and the other was physically or chemically weak-bounded niacin.
We propose that available niacin should be measured besides total niacin in the case of niacin assay in cereals and cereal products.
