EFFECT OF DRYING CONDITION ON MILLING QUALITY AND GERMINATION OF BRRI 29

Abstract

The objective of this study was to observe the effects of drying condition on milling quality and germination of BRRI 29. Experiment was conducted at Bangladesh Agricultural University (BAU) with both raw and parboiled paddy and raw paddy was procured from BAU farm in three batches. Initial moisture content of the raw paddy was 20.19%, 19.73% and 18.73% and that of parboiled paddy 36.46%, 33.65% and 32.71% of corresponding batches. For drying raw and parboiled paddy both sun and mechanical drying method were applied. Conventional sun drying method common to our country was applied for sun drying and for mechanical drying cabinet dryer was used. The study showed that for a specific moisture ratio raw paddy requires more time to dry under similar drying condition than parboiled paddy. For removal of 90% moisture parboiled paddy took 5 hours and raw paddy required 10 hours. Tests on milling quality showed that sun dried (45C) paddy in double layer (5.32 kg/m) gave the highest head rice yield (67%) and the lowest head rice yield (36%) was given by sun dried paddy at 53C in single layer (2.66 kg/m) indicating the adverse effect of drying temperature on milling quality of paddy. For germination rate sun dried paddy and mechanically dried paddy at 45C gave the best result while paddy dried at 40C, 49C and 50C gave poor result in this regard.