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

Document Type : Research and Review Papers

Authors

1 Food Science and Nutrition Department, Faculty of Agriculture, Sohag University, Egypt

2 Food Science Department, Faculty of Agriculture, Minia University, Egypt

Abstract

Nutritional value of pulses is a widely accepted but the
presence of antinutritional factors in its composition imposes a
restriction in its consumption. Soaking and germination process
on the removal or reducing of (total phenolic, tannins and
phytic acid) of commonly consumed legumes in Egypt were
studied. Four legumes namely faba bean (Vicia Faba ) Giza
843, chickpea (Cicer arietinum) Giza 1, cowpea (Vigna
unguiculata) krymy 7 and soybean ( Glycine max ) Giza 111,
were investigated. Soaking for 12 hours and germination for
different time periods (24, 48 and 72 h) contributed
significantly reducing in the total phenolic compounds, tannins
and phytic acid content of legumes. Phenolics compounds
content of raw legumes were, 370.9, 132.5, 763.4 and 249.4
mg/100g, while, tannin contents were, 684.5, 488.1, 390.9 and
225.5 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 12
hours significantly decreased the concentration of total
phenolics, tannins and phytic acid contents of the investigated
legumes 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 the
obtained results it could be observed that the removal extent of
antinutritional factors was increased with the progress of
germination periods in all studied legumes .

Keywords