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Phytic acid, in vitro protein digestibility, dietary fiber, and minerals of pulses as influenced by processing methods


The objective of this project was to determine the effect of various types of processing on selected nutrition related parameters of commonly consumed Indian pulses and soybean. Germination reduced the phytic acid content of chickpea and pigeonpea seeds by over 60%, and that of mung bean, urd bean, and soybean by about 40%. Fermentation reduced phytic acid contents by 26–39% in all these legumes with the exception of pigeonpea in which it was reduced by more than 50%. Autoclaving and roasting were more effective in reducing phytic acid in chickpea and pigeonpea than in urd bean, mung bean, and soybean. Germination and fermentation greatly increased the in vitro protein digestibility (IVPD). IVPD was only slightly increased by roasting and autoclaving of all legumes. Germination and fermentation also remarkably decreased the total dietary fiber (TDF) in all legumes. Autoclaving and roasting resulted in slight increases in TDF values. All the processing treatments had little effect on calcium, magnesium and iron contents.

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Correspondence to U. Singh.

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Chitra, U., Singh, U. & Venkateswara Rao, P. Phytic acid, in vitro protein digestibility, dietary fiber, and minerals of pulses as influenced by processing methods. Plant Food Hum Nutr 49, 307–316 (1996).

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Key words

  • Legumes
  • Pulses
  • Phytic acid
  • In vitro protein digestibility
  • Germination
  • Fermentation
  • Autoclaving
  • Roasting