Pearl millet at various moisture content (6.2, 9.4 and 12.3%, d.b.) and feed rates (3, 6 and 9 kg/h) was ground using hammer mill and its physical properties viz. arithmetic mean diameter, geometric mean diameter,...Pearl millet at various moisture content (6.2, 9.4 and 12.3%, d.b.) and feed rates (3, 6 and 9 kg/h) was ground using hammer mill and its physical properties viz. arithmetic mean diameter, geometric mean diameter, thousand grain weight, aspect ratio, specific surface area, surface area and bulk density were studied. Sieve analysis results showed that the increase in moisture content produced more medium sized particles with decreased percent weight retained in pan. Bond's work index, Kick's constant and average particle size were increased with the decrease in total surface area at higher moisture levels. The highest energy (2.34 KWh/kg) was consumed for 12.3% moisture content. Various grinding characteristics were significantly affected by moisture content and feed rate either individually or in combination and correlated in terms of Bond's work index, Kick's constant, total surface area, average particle size, effectiveness of milling and bulk density. Milling loss was found to be higher at lower moisture level and decreased with the increase of moisture content as well as feed rate. The loose and compact bulk density was ranged between 46.8-199.5 kg m^-3and 53.5-254.1 kg m^-3, respectively among the entire sieve fractions. Water absorption capacity increased with the decrease in particle size,展开更多
Indian traditional sweet dish i.e. halwa was developed from pearl millet grains. Pearl millet grains (Pennisetum typhoides var. PHB-2168) were steamed for 20 min at 1.05 kg cm^2 in order to minimize lipase activity,...Indian traditional sweet dish i.e. halwa was developed from pearl millet grains. Pearl millet grains (Pennisetum typhoides var. PHB-2168) were steamed for 20 min at 1.05 kg cm^2 in order to minimize lipase activity, total phenols, phytic acid and tannins content. Steamed grains were dried (12 ± 0.5% moisture content), pearled, milled, sieved through sieve opening size of 0.234 mm and were used for study. Central composite rotatable design (CCRD) with three independent variables i.e. vanaspati, sugar and water for rehydration were used to design the experiments. Sensory responses and rehydration ratio were used to study the individual and interactive effects of variables. Sensory score for colour varied from taste 6.3-7.9, mouth feel 6.4-7.8, overall acceptability (OAA) 6.5-7.9 and rehydration ratio (RR) from 1.4 to 2.3. All the responses fitted into quadratic equation with R2 〉 0.80. Halwa dry mix was also evaluated for stability in polyethylene pouches at ambient conditions and the peroxide and free fatty acids value were 21.35 meqO2 kg^-1 fat, 0.55% (oleic acid), respectively after 6 months of storage. Based on compromise optimization, optimum levels of the ingredients recommended with 86.4% desirability were: vanaspati 38.6 g 100 g^-1 pearl millet semolina (PMS), sugar 88.7 g 100 g^-1 PMS and water for rehydration 151 mL 100 g^-1 dry mix.展开更多
文摘Pearl millet at various moisture content (6.2, 9.4 and 12.3%, d.b.) and feed rates (3, 6 and 9 kg/h) was ground using hammer mill and its physical properties viz. arithmetic mean diameter, geometric mean diameter, thousand grain weight, aspect ratio, specific surface area, surface area and bulk density were studied. Sieve analysis results showed that the increase in moisture content produced more medium sized particles with decreased percent weight retained in pan. Bond's work index, Kick's constant and average particle size were increased with the decrease in total surface area at higher moisture levels. The highest energy (2.34 KWh/kg) was consumed for 12.3% moisture content. Various grinding characteristics were significantly affected by moisture content and feed rate either individually or in combination and correlated in terms of Bond's work index, Kick's constant, total surface area, average particle size, effectiveness of milling and bulk density. Milling loss was found to be higher at lower moisture level and decreased with the increase of moisture content as well as feed rate. The loose and compact bulk density was ranged between 46.8-199.5 kg m^-3and 53.5-254.1 kg m^-3, respectively among the entire sieve fractions. Water absorption capacity increased with the decrease in particle size,
文摘Indian traditional sweet dish i.e. halwa was developed from pearl millet grains. Pearl millet grains (Pennisetum typhoides var. PHB-2168) were steamed for 20 min at 1.05 kg cm^2 in order to minimize lipase activity, total phenols, phytic acid and tannins content. Steamed grains were dried (12 ± 0.5% moisture content), pearled, milled, sieved through sieve opening size of 0.234 mm and were used for study. Central composite rotatable design (CCRD) with three independent variables i.e. vanaspati, sugar and water for rehydration were used to design the experiments. Sensory responses and rehydration ratio were used to study the individual and interactive effects of variables. Sensory score for colour varied from taste 6.3-7.9, mouth feel 6.4-7.8, overall acceptability (OAA) 6.5-7.9 and rehydration ratio (RR) from 1.4 to 2.3. All the responses fitted into quadratic equation with R2 〉 0.80. Halwa dry mix was also evaluated for stability in polyethylene pouches at ambient conditions and the peroxide and free fatty acids value were 21.35 meqO2 kg^-1 fat, 0.55% (oleic acid), respectively after 6 months of storage. Based on compromise optimization, optimum levels of the ingredients recommended with 86.4% desirability were: vanaspati 38.6 g 100 g^-1 pearl millet semolina (PMS), sugar 88.7 g 100 g^-1 PMS and water for rehydration 151 mL 100 g^-1 dry mix.