GBR grain colour
The L*, a* and b* characteristics of GBR are shown in Figure 5. The colour of the GBR grain darkened significantly (p≤0.05) over the time of soaking. The result showed that BR grains were lighter (high value of L*) less red (low value of a*) and less yellow (low value of b*). The GBR samples were brownish in colour and with increasing germination time, they became a deeper brown. It has been hypothesized that the variation in colour values among the samples may be attributed to the amount of reducing sugar and amino acid content due to their role in the development of non enzymatic browning [31]. The Maillard reaction (a non enzymatic browning reaction) is a complex set of reactions, initially between a reducing sugar and amino acid [32]. Enzymatic browning reaction from polyphenol oxidase or peroxidase also occurs [33]. GABA increases pigment formation [34]. Thus GBR grains were darker as the soaking time increased.