Rice protein (2.4 g) was dispersed in 200 ml deionised water
and the pH was adjusted to 12 with 10 M NaOH. The protein was
thoroughly dispersed by vigorous and continuous agitation for
1 h. Glucose (2.4 g) was added to the dispersion. The pH of dispersion
was readjusted to pH 11 with 0.1 M HCl. Aliquots of 15 ml
were transferred to each of twelve 50 ml screw-capped glass
tubes; they were capped to prevent evaporation during heating.
The samples were heated in a water bath at 100 C. Two sample
tubes were removed during heating at the following times: 0, 5,
10, 15, 20, and 30 min. When removed the tubes were immediately
placed in an ice-bath and then stored at 4 C prior to analysis. Two
additional samples were removed after 15 min of heating and
freeze–dried and used for further experiments. Samples with other
pH values, reaction temperatures, and ratios of protein to reducing
sugar were prepared by the same procedure.