Rapid Measurement of Phytate in Soy Products by Mid-infrared Spectroscopy

The definitive version is available at www3.interscience.wiley.comThe rapid measurement of phytate from soybean and its products, such as soy flour, defatted meal, soymilk, and tofu, was investigated using Fourier transfer infrared spectroscopy (FT-IR) with an attenuated total refraction accessory. The phytate, separated from protein by trichloroacetic acid (TCA), was precipitated completely by the addition of calcium, pH > 7.0, even in the presence of TCA. The precipitate was dissolved in citrate buffer (pH 6.0) and then used for infrared measurement. The absorbance at 1070 cm−1 correlated well the phytate content of the each sample. The measurement of phytate can be done rapidly by FT-IR with an ATR accessory and gives reproducible values