ead rice yield (HRY) is a primary measure of milling
quality. HRY is defined as the mass percentage
of rough rice that remains as head rice (milled
kernels that are at least three-fourths of the original
kernel length) after complete milling. Currently, brokens
are sold at less than 60% of the price of head rice. Because
of this premium for head rice relative to brokens, HRY is a
direct determinant of economic return. A number of interrelated
factors during growing and processing, including kernel
physicochemical properties and environmental conditions,
determine rice milling quality.