STUDY ON THE DRIED YIELD RATE AND FOREIGN MATERIAL CONTENTS FOR PADDY DRYING IN DRYING CENTERS

摘要

Due to the climate and geographical surrounding in Taiwan, most farmers traded their harvested paddy with moisture within the range of 23～33%w.b. directly to the Farmer's Association or local grain merchants, and obtained a return of the dried equivalent on the basis of a rough estimation, followed by a certain exchanging rule. However, a fair standard of conversion is a must to reveal the relationship between the harvested and the dried paddy during the trading process and thus becomes a critical subject in Taiwan. In this study, 57 batches (dryers) of samples were investigated. The results of analysis showed that there existed a linear relationship between the dried yield rate (DYR) of paddy and moisture content (MC) with coefficient of determination 0.4881. Slop is -1.0617 and intercept is 109.86. In addition, coefficients of the linear regression equation with multivariable are -0.9471 on moisture content (M.C., %w.b.) and -0.8053 on pneumatic impurities selecting ratio (PISR, %) and the intercept is 109.22 with coefficient of determinations 0.5523 °The relationships between foreign material contents and the other wet grain physical properties were insignificant, however. There is no significant effect for rice species and crops on foreign material content. Further efforts are required to precisely predict the wet rice quality, as far as the foreign material contents are concerned. For the time being, farmer's association or regional drying center predicted the dried yield rate with the standard conversion equation between wet and dry rice. The mean error of such conversion found to be -1.647% in this study. The standard deviation of predicted value is 3.258%. The conversion equation needs to be improved.