In vitro solubility of calcium, iron and zinc in relation to phytic acid levels in rice-based consumer products in China

Int J Food Sci Nutr. 2010 Feb;61(1):40-51. doi: 10.3109/09637480903229017.

Abstract

In vitro solubility of calcium, iron and zinc in relation to phytic acid (PA) levels in 30 commercial rice-based foods from China was studied. Solubility of minerals and molar ratios of PA to minerals varied with degrees of processing. In primary products, [PA]/[Ca] values were less than 5 and [PA]/[Fe] and [PA]/[Zn] similarly ranged between 5 and 74, with most values between 20 and 30. [PA]/[mineral] molar ratios in intensively processed products were lower. Solubility of calcium ranged from 0% to 87%, with the lowest in brown rice (12%) and the highest in infant foods (50%). Iron solubility in two-thirds of samples was lower than 30%, and that of zinc narrowly ranged from 6% to 30%. Solubility of minerals was not significantly affected by [PA]/[mineral]. At present, neither primary nor intensively processed rice-based products are good dietary sources of minerals. Improvements should be attempted by dephytinization, mineral fortification or, preferably, combination of both.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biological Availability
  • Calcium / chemistry
  • Calcium, Dietary*
  • China
  • Food Handling
  • Humans
  • Intestinal Absorption
  • Iron / chemistry
  • Iron, Dietary*
  • Minerals / analysis
  • Minerals / chemistry
  • Oryza / chemistry*
  • Phytic Acid / analysis
  • Phytic Acid / chemistry*
  • Solubility
  • Zinc / chemistry

Substances

  • Calcium, Dietary
  • Iron, Dietary
  • Minerals
  • Phytic Acid
  • Iron
  • Zinc
  • Calcium