ARS | Publication request: Rice Quality: What Can Be Measured?

Submitted to: Rice Utilization Workshop Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: June 19, 1999
Publication Date: N/A

Technical Abstract: Over the past 4 years a comprehensive research project has been conducted by in collaborating ARS Laboratories including the Quality Assessment Research Unit, The Rice Research Unit and the Food Processing and Sensory Quality Research Unit. This project has looked at taste and texture of rice as effected by milling, moisture and drying regime. The use of Near Infrared Spectroscopy (NIRS) to develop rapid methods to assess rice quality is an integral part of this research effort. Subsequently, a large data set of diverse rice samples was added to original study. Models for protein, apparent amylose, milling degree, whiteness and transparency were developed for protein and apparent amylose. Solid-state proton Nuclear Magnetic Resonance (NMR) was employed to determine the ration of alpha 1-6 to alpha 1-4 linkages in the amylose/amylopectin fraction. It is believed that the NMR determined 1-4/1-6 ratio may give a better correlation to rheological properties than the empirically determined amylose/amylopectin ratio. The data in Tables 1 and 2 show that most NIR instruments can provide adequate compositional assays for most constituents, but does not perform well for parameters where the starch/protein matrix defines functional properties, Table 3. Rice research needs better assays for starch, amylose, amylopectin, sensory and rheological properties for the future to adequately assess quality.