Chemical Characteristics and Mineral Contents in Whole rice grains, Hulls, Brown rice, Bran and Polished Ali Kazemi Rice in Gilan province - North of Iran

IJFAS 12/2013; 2(24):1203-1209.

ABSTRACT ABSTRACT: In this study, the concentrations of some mineral elements in whole rice grains, hulls, brown rice, bran and polished rice from 10 major Alikazemi rice farmlands from 10 cities: Rasht, Shaft, Khomam, Masal, Soumahe Sara, Roudbar, Fuman, Astaneh-e Ashrafiyyeh Lashtenesha, Kochesfehan from Gilan province in the north of Iran in 2013 were determined by Atomic Absorption Spectrophotometer. All samples were collected in during harvesting of rice (August to late September 2013 ) in Gilan fields. Fat binding capacity (FBC) and water binding capacity (WBC) contents of rice bran and husk fibers varied significantly (p<0.05) in different paddy fields from different cities in Gilan Province. Rudbar samples has the highest level of WBC in rice bran and husk fibers while Astaneh-e Ashrafiyyeh samples has the highest level of FBC. The results of this research revealed that the removal of husk layer during dehusking and polishing substantially reduces the mineral nutrient value of rice grains. In general, the bran contains higher levels of iron, Manganese and Copper. Mn and Cu were mainly located in the hull while Iron and Zinc located in the bran. Polishing substantially reduces the mineral nutrient value of rice grains as only 2% of the total manganese 6% of the total Zn and Fe , 1% of Cu remained in polished rice and mainly parts of mineral elements were removed by the milling process if the hull and bran were thoroughly polished.

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May 27, 2014