ABSTRACTBrabender viscograms of 45 rice varieties, belonging to eight distinct property profiles, were determined at several slurry concentrations each. The conventional criteria, viz. peak viscosity (P), breakdown and setback, obtained at an arbitrarily fixed slurry concentration, did not provide useful information. For each rice variety there was aPvalue below which the breakdown was zero but rose progressively above it, as well as anotherPvalue at which the setback was zero but became positive below and negative above it. These two criticalPvalues were fairly characteristic of the rice type: e.g. the zero‐set‐backPvalue rose from about 350 B.U. for rice varieties of Group VIII (waxy) to 3500 B.U. for those of Group 1 (some dwarfindica). But the most useful test criterion was the‘relative breakdown,’i.e. breakdown/(breakdown + setback). Its value, at aPvalue of 1000 B.U., rose from about 3 for Group I to 300 for Group VIII. The three mutual ratios of the peak, hot‐paste and cold‐paste viscosities provided other useful distinguishing criteria. These viscogram indices were closely related to the total and insoluble amylose contents of
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