QUALITY OF RAW, EXTRUDED AND PARBOILED RICE BRAN

Abstract

Rice is the second most consumed cereal in the world, having reached a global production of 661.3 millions of tons, in 2008. Rice bran, resulted from grain milling to obtain white rice or polished parboiled rice, has significant amounts of carbohydrates, proteins, lipids, soluble fiber, vitamins, and minerals. This study had the objective of evaluating some physicochemical and microbiological characteristics of raw rice bran (RRB), extruded rice bran (ERB), and parboiled rice bran (PRB). All the analyses were done according to standardized methods recommended by the Brazilian National Health Vigilance and International Association of Official Analytical Chemists. The PRB presented the highest contents of protein (17.17 g 100 g^-1), lipids (36.03 g 100 g^-1), dietary fiber (34.06 g 100 g^-1), calcium (99.45 mg 100 g^-1), zinc (15.58 mg 100 g^-1), cupper (1.45 g 100 g^-1), and manganese (17.81 g 100 g^-1), and the lowest levels of carbohydrate (5.73 g 100 g^-1), ash (7.01 g 100 g^-1), potassium (507.55 mg 100 g^-1), and iron (6.83 mg 100 g^-1). All the rice bran samples showed Aspergillus sp. contamination, but ERB had the lowest colonies counting. All samples showed acceptable microbiological patterns for coliforms at 45ºC and Bacillus cereus, and Salmonella sp. absence, according to the Brazilian legislation. The RRB, ERB, and PRB have high nutritive value, being considered good sources of proteins, lipids, dietary fiber, and minerals.

KEY-WORDS: Oryza sativa L.; macronutrients; minerals; fungi.