Calculations and statistical analyses
The colour parameters were L*, lightness, which
ranges from 0 for black to 100 for white, a* for
red/green chromaticity and b* for yellow and blue
chromaticity, in accordance with the recommendations
of the International Commission on Illumination
(CIE 1976). From the a* and b* values, the
hue (Hab) and chroma (Cab) values were calculated.
Hue, namely the visible colours in the electromagnetic
spectrum (e.g. red, blue and yellow), provides
an angular measurement where 08 indicates a red
hue, 908 denotes a yellow hue, 1808 green and
2708 blue. Hue is calculated using the equation,
Hab = arctan (b*/a*) (Hunt 1977). Chroma is an