Thin layer chromatographic determination of aflatoxins in dry ginger root and ginger oleoresin

A method for determining aflatoxins in dry ginger root and ginger oleoresin, using 1-dimensional thin layer chromatography (TLC) for the determinative step, has been developed. The key cleanup steps that permit this change from the 2-dimensional TLC previously required are partitioning of the extract with carbon tetrachloride and use of an improved eluting system for the silica gel adsorption column. Recoveries of alfoxins B1, B2, G1, and G2 added to samples of ground ginger were 82, 101, 106, and 110%, respectively; recoveries of these aflatoxins added to ginger oleoresin were 75, 100, 93, and 125%, respectively. The method is applicable to fish meal and a number of mixed feeds.