Determination of Nicotinic Acid and Nicotinamide in Meats by High Performance Liquid Chromatography and Conversion of Nicotinamide in Meats during Storage

Abstract

A method for determination of nicotinic acid (NA) and nicotinamide (NAA) in meat by high performance liquid chromatography (HPLC) was developed.NA and NAA were extracted from meat with methanol and the extract was cleaned up with a Sep-pak alumina N cartridge. NAA was eluted with methanol and NA was eluted with 0.1M sodium hydrogencarbonate from the cartridge. NA and NAA in each eluate were separated on a column packed with LiChrosorb RP-18 by using methanol-acetate buffer (pH 5) containing 0.1M sodium acetate and 0.01M tetrabutylammonium hydroxide (2:10v/v%), as a mobile phase, with detection at 261nm. Recoveries of NA and NAA from ground meats spiked at levels of 0.5 and 2.0mg/100g were more than 92%. NA was detected in 24 of 155 samples of commercial ground meat at the level of 1.1-45.7mg/100g and NAA was detected in all of the samples at the level of 1.1-5.9mg/100g.The effect of storage time on content of NA an NAA in meat at -18, 4, 10 and 25°C was examined. At 10°C, NAA content began to decrease on the 2nd day and NAA was no longer detected on the 5th day, whereas NA began to be detected on the 2nd day and its content subsequently rapidly increased. The total amount of NA and NAA in one sample was approximately constant during storage.Based on these results, NAA in meat appears to be converted to NA during sotrage.