OCHRATOXIN A AND AFLATOXINS B1, B2, G1, G2 IN GRAPE JUICE: SIMULTANEOUS ADSORPTION WITH ACTIVATED CARBON

Abstract

Ochratoxin A (OTA) and aflatoxins B1, B2, G1 and G2, are produced by fungi which develop in the vineyard and they appear in products obtained from contaminated grapes, such as wine, raisins and must. These toxins are considered harmful to living beings. In this work activated carbon (AC) was used as adsorbent material for OTA and aflatoxins jointly. The adsorbent material tested was obtained from grape stalk. It was produced by carbonization and subsequent physical activation with steam. In order to perform the adsorption tests a sample of sulphited must was seeded with OTA and aflatoxins. Three samples of 200 ml were taken. Each one of them was contacted with 25, 50 and 100 mg of activated carbon, with continuous agitation to 300 K. In each test the concentration of mycotoxins at 30, 60 and 120 minutes was determined by extraction with immunoaffinity columns and subsequent quantification by HPLC. In all tests a concentration decrease of mycotoxins was obtained, according to the amount of coal used. The OTA had better adsorption (96%). The aflatoxins B1 and B2 appear to have higher affinity with the adsorbent (95% and 93% respectively). Aflatoxins G1 and G2 had 85% and 80% abatement respectively.