Zinc fortification: Effect of polishing on parboiled and unparboiled rice

Abstract

Zinc (Zn) deficiency is one of the causes of anemic disease and mortality in developing countries where rice is the staple food. Such deficiency is enhanced with over polishing of rice grains. Grain Zn contents can be improved through fortification. Agronomic fortification through the use of Wuxal Zn and Antracol (Zn containing fungicide) were tested with BRRI dhan58 and BRRI dhan74 (Zn enriched variety) and compared with no spraying conditions on grain Zn contentin two locations of Bangladesh during 2016-17. Grain yield increased with Zn spraying by about 2–10% for BRRI dhan58 and about 6–18% for BRRI dhan74 compared to control. Grain Zn content in brown rice of BRRI dhan58 under control condition was about 17 mg kg−1 that increased to about 19 mg kg−1 through Zn spraying. Similarly, Zn content of BRRI dhan74 varied from 22.02 to 23.78 mg kg-1 under control condition, which increased to 24.25–25.79 mg kg−1 after Zn spraying. Grain non-parboiled polishing at 9–10% reduced Zn content by about 2.6–5.84 mg kg−1 irrespective of varieties and locations. Zinc enrichment through agronomic practices and awareness buildup on reduced polishing would be the important options for improving rice grain nutritional quality in Bangladesh. Keywords: Rice, Paddy soil, Zn spraying, Grain yield, Polishing, Zn enrichment