Dependence of aflatoxin in almonds on the type and amount of insect damage

The aflatoxin distribution of single insect damaged Nonpareil almonds (1999 crop) has been measured. Separate distributions were obtained for pinhole, insect (feeding), and gross damage. Only a low level of aflatoxin contamin ation ([c] = 0.0003 ng/g) was found for pinhole-only damaged nuts. The dist ributions for insect and gross damage did not differ, but did differ signif icantly from the distribution previously obtained for gross damaged Ne Plus almonds from a different producer (Schatzki, T. F.; Ong, M. S. J. Agric. F ood Chem. 2000, 48, 489-492; also 1999 crop). The Nonpareil almond distribu tion could be explained on the basis of a preharvest hull splitting, simila r to previous results in pistachios (0-4 weeks versus 2-6 weeks preharvest) . The Ne Plus distribution differs in detail from pistachio results and fro m the Nonpareil results found here. This may indicate additional cultural d amage of Ne Plus almonds around harvest time and/or use of different sortin g parameters. Aflatoxin lot averages of 31.7 and 3.47 ng/g were obtained fo r 100% insect damaged Ne Plus and Nonpareil almonds, respectively. (The pre vious Ne Plus work contained a calculation error, which is corrected here.) The distribution functions were used to compute the seller's risk of nonac ceptance of lots in the European Union. To obtain a 95% acceptance rate, af latoxin B-1 levels of 0.12 and 0.22 ng/g would be required, which would cor respond to 3.8 and 1.2% (feeding and gross) insect damage in Nonpareil and Ne Plus almond lots, respectively.