The Anti-nutritional Effect of Phytate on Zinc, Iron and Calcium Bioavailabilities of Some Cereals Staple Foods in Zaria, Nigeria

Aim of Study: To evaluate the effect of phytate on the bioavailabilities of zinc, iron and calcium of some cereals staple foods in Zaria, Nigeria.

Study Design: Experimental.

Place of Study: Department of Biochemistry, Faculty of Sciences, Ahmadu Bello University Zaria, Nigeria.

Methodology: Tuwon surfafen masara (TSM) was prepared by first milling the processed maize. Tuwon masara (TM) and Pap were prepared using standard local preparation methods. Phytic acid content was determined according to the method described by Reddy; The minerals were determined using atomic absorption spectrophotometry; AOAC 1990. Data was analysed with one way ANOVA and differences were considered significant at P = .05.

Results: The ratios of Phytate:Ca, Phytate:Fe, Phytate:Zn for Tuwon surfafen masara were found to be 0.0026, 0.197 and 0.429 respectively. While that of Tuwon masara was 0.0044, 0.127 and 0.376 respectively. Accordingly pap showed a phytate to mineral ratios of 0.0025, 0.043 and 0.162 for Phytate:Ca, Phytate:Fe and Phytate:Zn respectively. The ratios of Phytate:Ca, Phytate:Fe and Phytate:Zn for local rice (LR) was found to be 0.0075, 0.110 and 0.625 respectively. While that of foreign rice (FR) was 0.0031, 0.046 and 0.266 respectively. The phytate to mineral ratios of all the staple foods in the present study falls below the critical values of >0.24, >1 and >18 for Phytate:ca, Phytate:Fe and Phytate:Zn respectively which indicate good bioavailability.

Conclusion: The result obtained showed that the bioavailability of Ca, Fe and Zn in TSM, TM, Pap, LR and FR in Zaria, Nigeria is not affected by their phytic acid contents.