Physico-Chemical Properties of Coarse Rice Cultivars Grown in Different Areas of Punjab and Sindh, Pakistan

Abstract

Rice (Oryza sativa L) is the second largest important cultivated cereal. Rice being an invaluable alternative source of carbohydrate being easily digestible and has rare allergic reactions. Coarse rice is known for its puffing characters and used in many puffed or extruded products. Puffed rice is also very popular in other countries as breakfast cereal and essential component of cereal based snacks.   Five coarse rice varieties namely IRRI-9, IRRI-6, KSK-133, KSK-434 and Shadab were milled to obtain brown rice and white rice. Proximate composition revealed that protein, ash, fat and fiber were significantly higher in brown rice than white rice. The length (7.67mm) and width (2.35mm) was higher in KSK-434 whereas higher thickness (2.05mm) was observed in KSK-133. The highest bulk density (0.93g/cm³) was observed in IRRI-6 whereas IRRI-9 shows lowest (0.88g/cm³) values. Thousand kernel weight (TKW) was ranged from 15.83 to 20.02g and 18.28 to 22.84g among the milling fractions of white and brown rice, respectively. Thousand kernel weight was found to be higher in KSK-434 followed by Shadab, KSK-133 and the lowest values were observed in IRRI-9. Moisture, ash, fiber, protein, fat and NFE (nitrogen free extract) contents ranged from 9.23 to 12.26g/100g, 0.67 to 3.81g/100g, 0.98 to 4.21g/100g and 6.04 to 8.98g/100g, 1.23 to 5.45g/100g and 65.87 to 80.28g/100g respectively among different milling fractions. The amylose contents for IRRI-9, IRRI-6, KSK-133, KSK-434 and Shadab ranged from 27.07 to 28.25%, 27.55 to 29.78%, 26.48 to 27.96%, 26.80 to 28.98% and 29.03 to 30.88% respectively among different varieties. With respect to amylose, length, thousand kernel weight and bulk density, higher values were observed in KSK-434 and Shadab. Shadab shows best values (higher amylose and lower protein) for extrusion and puffing purposes. Brown rice showed higher nutritional values with respect to protein, fiber, ash (minerals) and fat.

Keywords: Brown rice, White rice, Amylose, Fractions, Coarse rice

DOI: 10.7176/JBAH/9-5-02

Publication date:March 31^st 2019