Cereal Chem 40:323 - 336.  |  VIEW ARTICLE

Influence of Maturity on Properties of Western Rices.

E. B. Kester, H. C. Lukens, R. E. Ferrel, A. Mohammad, and D. C. Finrock. Copyright 1963 by the American Association of Cereal Chemists, Inc. 

Chemical constituents and physical properties of rice change as the rice matures. Measurements made on Calrose, Caloro, and Colusa varieties revealed that maximum yields of head rice and minimum hot paste viscosity and water absorption occurred early in the maturation process, and then the trends reversed. Amylolytic activity was highest at the point of trend reversal. Reflectance properties shifted direction simultaneously. Rice harvested at mid-season showed the most yellow color, the lowest lightness and whiteness values, and the least chalkiness. Chlorophyll was detectable in the midharvest season, but disappeared several days later when translucency, as measured by light transmission, reached near maximum values. The late stages of maturity were characterized by loss of yellow color, increasing lightness and whiteness values, but little change in chalkiness. Other properties trended upward or downward to plateaus, or showed little change.