POLYPHENOLS, TANNINS AND PHYTATE CONTENTS IN SOME EGYPTIAN LEGUMES AS AFFECTED BY SOAKING AND GERMINATION PROCESSES

Abstract

Nutritional value of pulses is a widely accepted but thepresence of antinutritional factors in its composition imposes arestriction in its consumption. Soaking and germination processon the removal or reducing of (total phenolic, tannins andphytic acid) of commonly consumed legumes in Egypt werestudied. Four legumes namely faba bean (Vicia Faba ) Giza843, chickpea (Cicer arietinum) Giza 1, cowpea (Vignaunguiculata) krymy 7 and soybean ( Glycine max ) Giza 111,were investigated. Soaking for 12 hours and germination fordifferent time periods (24, 48 and 72 h) contributedsignificantly reducing in the total phenolic compounds, tanninsand phytic acid content of legumes. Phenolics compoundscontent of raw legumes were, 370.9, 132.5, 763.4 and 249.4mg/100g, while, tannin contents were, 684.5, 488.1, 390.9 and225.5 mg/100g, and phytic acid content was, 1050.6 , 719.2,987.2 and 1076.2 mg/100g on dry weight basis in faba bean,chickpea, cowpea and soybean, respectively. Soaking for 12hours significantly decreased the concentration of totalphenolics, tannins and phytic acid contents of the investigatedlegumes by 4.0-22.7, 7.1-26.5 and 7.0-15%, respectively.Germination process for 72 hours reduced total phenolics,tannins and phytic acid contents of studied legumes by 21.4 -56.9, 23.9-64.8 and 54.6-65.0%, respectively . From theobtained results it could be observed that the removal extent ofantinutritional factors was increased with the progress ofgermination periods in all studied legumes .