Genotypic variation in milling depression of iron and zinc concentration in rice grain
- 880 Downloads
Background and aims
The loss of iron and zinc during milling to produce white rice can have serious consequences for human health. Therefore, the objective was to evaluate Fe and Zn partitioning between the endosperm, bran and embryo, and the milling loss of these nutrients among Thai rice genotypes.
Concentrations of iron and zinc and their partitioning to different parts of the grain were examined in 15 genotypes of Thai rice (10 belonging to the long-slender grain type) grown together under wetland condition.
The depression in grain Fe and Zn concentrations (24–60 and 10–58 %, respectively) on milling differed among rice genotypes and were affected by the extent of differential partitioning of Fe and Zn into different parts of the grain. For example, nearly 70 % of white rice Zn was allocated to the endosperm in contrast to only 43 % for Fe.
Because of variation in milling loss of Fe and Zn, that can result from genotypic variation in the degree of milling and partitioning of Fe and Zn into different parts of the grain, we conclude that white rice Fe and Zn concentrations should not be inferred solely from brown rice concentrations of these nutrients.
KeywordsBrown rice Degree of milling Long-slender grain type Milling loss White rice
The first author is a recipient of a Royal Golden Jubilee PhD scholarship. Support from Research University Project of Thailand’s Commission of Higher Education is also gratefully acknowledged. We thank Dr. Sittichai Lordkaew, Chiang Mai University for help with chemical analysis.
- Allan JE (1961) The determination of zinc in agricultural material by atomic absorption spectrophotometry. Analyst 96:531–534Google Scholar
- FAO/WHO (1998) Vitamin and mineral requirements in human nutrition: report of a joint FAO/WHO expert consultation, Bangkok, Thailand, 21–30 September 1998Google Scholar
- Hotz C, Brown KH (2004) Assessment of the risk of zinc deficiency in populations and options for its control. Food Nutr Bull 25:94–204Google Scholar
- Juliano BO (1993) Rice in human nutrition. Food and agriculture organization of the United Nations, RomeGoogle Scholar
- Palawisut S, Nualsiri P, Patirupanusara P, Patirupanusara T, Noenplab ANL, Chiengwattana N, Pattawatang P, Suwanthada S, Chairinte S, Suttayot S, Anawong J, Palawisut W, Intrarasatit W, Wannasai C, Ariyapruek D, Hintang P, Wangka M, Deerasamee C, Sanguansaj T, Varamisara V, Karnjanaphun S, Pipatpiriyanon J, Kongtong T, Sriratanasak W, Chansrisommai N, Tayatum C, Chettanachit D, Nilpanit N (2008) RD29 (Chainat 80) rice variety. Thai Rice Res J 2:80–95Google Scholar
- Phattarakul N, Rerkasem B, Li LJ, Wu LH, Zou CQ, Ram H, Sohu VS, Kang BS, Surek H, Kalayci M, Yazici A, Zhang FS, Cakmak I (2012) Biofortification of rice grain with zinc through zinc fertilization in different countries. Plant Soil. doi: 10.1007/s11104-012-1211-x
- Ren X, Liu Q, Fu H, Wu D, Shu Q (2006) Variations in concentration and distribution of health-related elements affected by environmental and genotypic differences in rice grains. Rice Sci 13:170–178Google Scholar
- Senadhira D, Gregorio GB, Graham RD (1998) Breeding Fe and Zn dense rice. Los Banos, Laguna, Philippines, IRRIGoogle Scholar
- Sison MEGQ, Gregorio GB, Mendioro MS (2006) The effect of different milling times on grain iron content and grain physical parameters associated with milling of eight genotypes of rice (Oryza sativa). Phil J Sci 135:9–17Google Scholar
- Sun H, Siebenmorgan TJ (1993) Milling characteristics of various rough rice kernel thickness fractions. Cereal Chem 70:727–733Google Scholar
- WHO (2002) World health report 2008. World Health Organization, GenevaGoogle Scholar