Abstract
The most reliable assay method for niacin (a combined name of nicotinic acid + nicotinamide) in food is said to be microbial method at present. The authors investigated the assay method of niacin by HPLC in order to simplify the procedures and to save the assay time. 1) In order to determine niacin i food in the form of nicotinic acid, conditions for 2 fours with 0.5 M sulfuric acid was suitalble for the hydrolysis. 2) The limit of analysis of the present HPLC method under the above conditions was 0.1 mg/100 g food. The range recovery of nicotinic acid and nicotinamide spiked was between 100 and 104%, respectively. 3) Niacin contents in 35 kinds of food were assayed by HPLC and microbial methods. Values obtained by these two methods coincided well with each other.
