Determination of aflatoxin B-1 in pistachio kernels and shells

A method was developed for accurate measurement of aflatoxin B-1 in the edible portion of pistachio nuts, Twenty-nine samples of kernels with and without their shells were slurried with a Mega Ultra Turrax, A subsample of the homogenate was extracted with water-methanol, defatted with petroleum ether, purified with a silica solid-phase extraction column, and redissolved in methanol, After separation on an octadecyl column and postcolumn reaction with on-line electrochemically generated bromine, the aflatoxin B-1 derivative was detected fluorometrically, The shells contained less than 1% of the aflatoxin B-1 found in the edible kernel, and they accounted for 41.7-46.8% of the weight of the whole pistachio, These observations indicate it is possible to analyze an entire sample, up to 25 kg, as a whole and still be able to judge whether it meets the legal tolerance limit of 5 mu g aflatoxin B-1/kg edible part, as set by the Dutch Food Act.