Physicochemical properties were determined with seven kinds of rice (long-grain variety) collected locally in the countries, Thailand and the Philippines. The results obtained were as follows;
(1) The moisture contents were slightly lower. The color tone of white rice was similar to that of common domestic products in Japan but the color degrees were numerically expressed for red and black rice, respectively. The protein contents were similar to those of domestic products in Japan. The amylose contents varied among samples those of the nonglutinous line spread over a wide range of 17.0-30.4%, while the contents of the glutinous line and dull endosperm line were 3.2% and 7.4%, respectively. The alkaline degradation was widely different among the samples.
(2) The compositions of main free sugars were glucose, sucrose and maltose, which were the same as those of Japanese products. The compositions of fatty acids were palmitic, oleic (O) and linoleic acid (L); which were the same as those of Japanese products but the O/L ratios in these samples were higher as a whole, and it was inferred that the stability of these fats might be high.
(3) The characteristic values obtained by viscogram showed remarkably high degree of retrogradation irrespective of the levels of amylose contents in the nonglutinous line. The factors responsible for the characteristic remain to be solved. The glutinous and intermediate glutinous lines showed similar viscosities to those of Japanese products. In these samples, it was also a striking characteristic that breakdown values were generally low.
