Phytate content of foods: Effect on dietary zinc bioavailability

Abstract

Phytale and zinc contents of different varities of rice, wheat and legumes were
analysed. Phytate content of rice ( perboiled, milled ) was found in the range o f 92.12
± 2.70 mg in Latisail to 225.29 ± 3.25 mg per lOOg edible portion in BR-22. In
legumes highest amount of phytate was found in Bengal gram (858.51 ± 2.50 mg
/lOOg EP) with a range of 489.2 ± 1.50 to 858.51 ± 2.50 mg per 100 g EP.Wheat flour
(whole) contained 720 ± 3.25 mg of phytate per 100 g EP while wheat flour (refined)
contained only 146.46 ± 1.29 mg of phytate. Zinc content o f different varities o f rice
varied from 0.58 ± 0.02 to 1.71± 0.09 mg per 100 g EP and in legumes it ranged from
2.31± 0.01 to 3.67 ± 0.05 mg per 100 g EP. Zinc content of wheat flour (whole) was
found higher (2.65 ± 0.05 mg /lOO g EP) than wheat flour (refined) (0.85 ± 0.09
mg/100 gm EP) Average phytate and zinc intake of Bangladeshi adult population was
calculated on the basis of daily per capita food intake. Average per capita phytate and
zinc intake was found to be 1036 mg and 8.0 mg respectively. Bioavailability o f zinc of
the diet was calculated on the basis of phytate-zinc molar ratio. Phytate - zinc molar
ratio was found to be 12.77 which Indicated that the bioavailability o f zinc was in the
range o f 30% to 35%.