Physicochemical properties of Aus cultivars in Bangladesh

A total of 17 Aus rice cultivars including 10 (ten) local cultivars like Surjamukhi, Burikatari, Sada Dumra, Chakilla, Agaua, Bir Madla, Panki Raj, Tubri, Phul Dumra, Kasalath and 7 (seven) modern HYV rice varieties like BR20, BR21, BR24, BR26, BRRI dhan42, BRRI dhan43, BRRI dhan48 were studied for a comparative study on physicochemical and cooking properties. The highest milling outturn 72.22% was found in the traditional variety Chakilla and lowest in Kasalath (65.43%). The highest milled rice length (6.5 mm) was BRRI dhan42 and the highest length-breadth ratio (3.8) was found in both BR24 and BR26. The lowest grain length was found in BR20 (5.0 mm) and lowest length-breadth ratio were found in Phul Dumra (2.0). Apparent Amylose content (AAC) of these cultivars range from 22.0% (Surjamukhi) to 27.0% (BR24, BRRI dhan43 and BRRI dhan48). All the varieties contain more than 7.6% of protein. Traditional Aus cultivars possess more protein content than BRRI varieties. Maximum cooking time (23:30 mins.) were required for Phul Dumra and minimum (15:30 mins) for BR21 rice. Elongation ratio (ER) of grains of local and modern Aus rice cultivars varied between 1.1 to 1.2 and 1.3 to 1.6 respectively. The highest imbibition ratio (IR) of 4.4 was found in BRRI dhan43. Among all studied cultivars, Surjamukhi has aroma and it has yellowish grain color with red pericarp. Chakilla has black grain color with red pericarp and rest of the traditional cultivars have white grain color and red pericarp. Modern HYV rices have white grain color and white pericarp.