Effect of Tempering Temperature and Time on the Quality of Semi-dry Black Glutinous Rice Flour

The effects of tempering temperature and time on semi-dry black glutinous rice flour's color value,quality index,physico-chemical properties and pasting properties were researched. It was concluded that as the temperature increased,the average particle size of the rice flour decreased,the color value increased first and then decreased,and the L^* reached the minimum at 55℃. The color of rice flour was fine as the b^* was lowest at 35℃ meanwhile the solubility was the lowest. The swelling degree was the lowest at 25℃. The tempering time had significant effects on peak viscosity,final viscosity,revalue. The color value and the average particle size of the black glutinous rice flour decreased as the tempering time extended while the solubility decreased first and then increased. The lowest solubility was 4.1% and the highest water-holding capacity of 40℃ was 2.43 g/g after 5 h tempering. The tempering time showed no significant influence on the swelling degree of black glutinous rice flour(P>0.05).