FORMATION OF BIOGENIC-AMINES IN IDIAZABAL EWES-MILK CHEESE - EFFECT OF RIPENING, PASTEURIZATION, AND STARTER

The importance of biogenic amines stems from their toxicity and their potential as a cause of food poisoning. After fish, cheese has been th e foodstuff most often responsible for cases of food poisoning caused by ingestion of biogenic amines. Changes in biogenic amine (histamine, tyramine, putrescine, cadaverine, tryptamine, isopentylamine, spermid ine, and phenylethylamine) content during the ripening of a cheese mad e from raw ewe's milk were studied, together with the effects of paste urization and a commonly used commercial starter and indigenous starte r cultures. Biogenic amines were determined by high-pressure liquid ch romatography following extraction from the cheese and derivatization w ith dansyl chloride. Levels of histamine, potentially the most toxic a mine, in the semihard Idiazabal cheese were very low. Tyramine, putres cine, and cadaverine were the main amines present in this type of chee se. Levels of those amines increased during ripening. Pasteurization o f the milk brought about a reduction in the biogenic amine content of the ripened cheese, irrespective of the starter culture employed. The indigenous starter cultures considered in this study produced higher l evels of histamine and cadaverine and lower levels of tyramine and put rescine than the commercial starter culture tested.