A survey of aflatoxins in peanut butters, nuts and nut confectionery products by HPLC with fluorescence detection.

A preliminary survey in 1982 of aflatoxin levels in peanut butters indicated that 31 out of 32 samples of major national brand-named products examined contained less than 10 micrograms/kg aflatoxin B1 and that 59% of these were below the limit of detection (2 micrograms/kg). In contrast, of 25 peanut butters from specialist 'Health Food' outlets, 64% contained less than 10 micrograms/kg aflatoxin B1, the remainder ranging from 16 to 318 micrograms/kg, with one sample having a total aflatoxin concentration of 345 micrograms/kg. Subsequent surveys in 1983 and 1984 of 'Health Food' products confirmed that these manufacturers were still experiencing some difficulty in complying with the 30 micrograms/kg total aflatoxin voluntary guideline limit. A further survey in 1984 was carried out of 228 retail samples of nuts and nut confectionery products comprising peanuts (shelled, unshelled, roasted and salted), mixed nuts, almonds (both unblanched and ground), brazils (in shell), hazelnuts (in shell), chocolate-coated peanuts, peanut brittle and coconut ice. The results showed that 74% of the samples contained less than 0.5 microgram/kg of aflatoxin B1 with 3.1% exceeding the guideline tolerance of 30 micrograms/kg total aflatoxins, these being predominantly peanuts and brazils. The highest total levels of aflatoxins observed were in unshelled peanuts containing 4920 micrograms/kg and in a composite sample of visibly moulded brazils containing 17 926 micrograms/kg.