The whiteness of milled rice samples during milling for
different varieties is shown in Fig. 3. Apparently the whiteness
increased rapidly in the beginning and was followed by
a gradual increase in latter stages heading towards to an
asymptotic value. These trends suggested that the bran layers
were quickly removed in the beginning as compared to
the mix of bran and starchy layer latter. The plot of WI
against milling duration was having similar shape as
HRY reduction and hence the same set of models were
tried for representing the plots. It was found that WI during
milling could be best represented by the relationship
given in Eq. (5) (analogy to Peleg model for water absorption
and desorption) based on R2 and RMSE (data not
shown). In a preliminary research study of the department,
the same relationship was used to representWI during milling
for SPR60 variety.