Determination of the phytic acid levels in infant foods using different analytical methods

The analytical methods of phytic acid determination in infant foods were evaluated, and then, the method suggested in this study was applied to determine the phytic acid level in commercially available infant foods for both the flour and paste types. The spectrophotometric (AOAC and Wade reagent) and chromatographic (GC-FID and HPLC) methods were compared, and the spectrophotometrically determined value showed higher phytic acid levels than that of the chromatographic methods (P < 0.05). The AOAC method showed a complete recovery for the infant foods after spiking the phytic acid, while a poor recovery was observed by GC-FID and HPLC-RI. The average levels of phytic acid in the infant foods determined by the AOAC methods were 363 mg/ 100 g for the flour type and 46.3 mg/100 g for the paste type on a wet basis. When the phytic acid level was converted into a dry basis, the phytic acid levels of the paste types were much higher than that of the flour type. Thus, the amount of phytic acid intake per meal was calculated, and the phytic acid level per meal was high in the paste type as wells as the flour type. Therefore, a problem with phytic acid might be considered for the infant foods of both the flour and paste types. (c) 2005 Elsevier Ltd. All rights reserved.