Monitoring of Natural Preservative Levels in Food Products

Food Safety Evaluation Department, Korea Food & Drug Adminstration, Seoul 122-704, KoreaAbstractIn the current food sanitation regulation, food additives are under controlled by the Food Code. The naturally derived preservatives such as benzoic acid and propionic acid can be naturally carried over or produced as metabolites during manufacturing process such as fermentation. To monitor naturally formed benzoic acid and propionic acid levels, a total of 145 samples were classified into berries (prune, cranberry), functional foods (propolis liquid, ginseng product), vinegars (vinegar-based drink, vinegar beverage, vinegar), and salted and pickled products (olive, pickled cucumber, salted/pickled product) and analyzed by HPLC-PDA and GC-FID. From the results, benzoic acid and propionic acid were each detected and identified in 144 samples and 64 samples respectively. The amount of benzoic acid ranged from 4.1～478.4 ppm in cranberry, from 49.7～491 in propolis liquid, and from 2.5～10.2 ppm in ginseng, and other tested samples contained very small quantity. Also, the amount of propionic acid ranged from 179.8～951.9 ppm (av. 553.6 ppm) in vinegar (persimmon vinegar 100%), which was the highest level among fermented foods, from 13.7～247.0 ppm in propolis liquid, from 2.0～180.7 ppm in vinegar-based drink, and from 1.6～76.6 ppm in olive. Vinegar beverage and pickled cucumber each showed 24 and 18 ppm of propionic acid; in contrast, propionic acid was not detected in prune, cranberry, ginseng, and picked/salted products.Key words: preservative, benzoic acid, propionic acid, origin of natural