COMPARATIVE STUDY ON PHYSICOCHEMICAL PROPERTIES AND MINERAL PROFILING OF HIGH YIELDING RICE VARIETIES (HYVs) IN BANGLADESH

Abstract

The study was conducted to explore a comparative study on physicochemical properties and mineral profiling of high yielding rice varieties (HYV) in Bangladesh. A total of ten different rice varieties evaluated for various quality aspects in terms of physicochemical, cooking, pasting and mineral characteristics at both unparboiled and parboiled condition. Among the ten rice varieties BRRI dhan62 had the highest broken rice percent and length breadth ratio (L/B). In both conditions, milling outturn (MOT) was found the highest values in BRRI dhan64. Head rice yield (HRY) was below 75% for all tested varieties. Cooking time (CT) varied ranges from 16.2 min to 20.5 min for all tested HYVs. BRRI dhan64 has the highest imbibition ratio (IR) in both conditions. The highest elongation ratio (ER) was observed in BR6 and BRRI dhan64 at unparboiled condition and BR6, BRRI dhan35, BRRI dhan36, BRRI dhan62 and BRRI dhan64 at parboiled condition. BRRI dhan43 and BRRI dhan62 have the highest (25.5%) and the lowest (18.5%) apparent amylose content (AAC) respectively in unparboiled condition. The highest AAC was found for BRRI dhan43 (26.8%) and the lowest for BRRI dhan74 (19.2%) at parboiled condition. Alkaline spreading value (ASV) of the tested HYVs ranges from 3.3 to 7.00. The highest ASV (7.00) and lowest ASV (3.3) were found in BRRI dhan36 and BRRI dhan62 respectively at unparboiled condition. The highest ASV (5.6) was observed in BR6 and BRRI dhan36 and lowest ASV (3.2) was observed BRRI dhan62 at parboiled condition. All tested HYVs showed moisture content ranges from 11.5% - 13.3%. We found that the range of protein content (PC) were 7.1% to 10.4% and the highest PC recorded was for BRRI dhan36 (10.4%) in selected popular BRRI HYVs in Bangladesh. A wide range of variation on the content of phytic acid and minerals like phosphorus, iron, zinc and calcium were found in the tested HYVs of rice at both unparboiled and parboiled condition. Among the tested HYVs, BRRI dhan42 and BRRI dhan43 contain lower content of phytic acid and higher content of minerals, likely zinc, iron, calcium and phosphorus.