LIQUID CHROMATOGRAPHIC DETERMINATION OF OCHRATOXIN A IN PURE AND ADULTERATED SOLUBLE COFFEE USING AN IMMUNOAFFINITY COLUMN CLEANUP PROCEDURE

摘要

An immunoaffinity column/HPLC procedure was developed to quantify low levels of ochratoxin A (OTA) in green coffee beans, roasted coffee beans, and soluble (instant) coffee with greater than 80% recoveries. The method was used to survey 116 soluble coffee samples from various countries and different manufacturers and showed contamination levels ranging from ''not detectable'' to 15.9 mu g/kg. The highest levels of OTA were detected among soluble coffees that had been adulterated with coffee husks and/or coffee parchments (mean contamination level: 5.9 mu g/kg). By comparison, OTA concentrations in pure soluble coffee samples were significantly lower, with a mean cont;amination level of 1.1 mu g/kg. Although higher than normal figures have been found in some products purchased in East European countries, the results of this survey indicate that pure soluble coffee is not a major source of OTA in the diet, with estimated intakes being well within safety limits.