Colorimetric determination of phytate in unpurified extracts of seeds and the products of their processing.

The addition of orthophosphate (up to 20 micrograms/ml of phosphorus) and chlorogenic acid (up to 50 micrograms/ml) does not impair the colorimetric assay of phytate based on the decoloration of Fe3+-sulfosalicylate complex (M. Latta, and M. Eskin (1980) J. Agric. Food Chem. 28, 1313-1315). Phytate was determined in 14 samples of seed meal and protein isolates containing inorganic phosphate and chlorogenic acid. There was no difference between the results of the analysis using crude extracts and those using purified extracts. It is therefore possible to avoid the preliminary purification of extracts as in the original method, thereby simplifying and accelerating the phytate assay to a considerable extent.