H. S. R. Desikachar and V. Subrahmanyan. Copyright 1960 by the American Association of Cereal Chemists, Inc.
The amylases were destroyed during the first 5 minutes of cooking milled rice grains, but the solids extracted by the cooking water continued to increase as cooking progressed. The inhibition of amylase action by mercuric salts did not improve the cooking quality of new rice; treatment with formalin or steam-curing of the freshly harvested rice did. The cooking of old rice in amylase solution did not affect its cooking quality. In aqueous suspensions, fresh-rice flour took more time to settle and left the supernatant liquid more turbid than old-rice flour under similar conditions. The physical changes that occur during storage have to be considered in explaining the improved cooking quality of old rice.