Singh et.al.

maturation and fruit colour turned yellow after

The strong linear relationship, in present study was

250 days. The minimum hue angle (h°=53.99±0.52)

found between a* and fruit development (R 2 = 0.96).

of fruit peel was recorded at the 240 DAFS. But the

The R 2 value indicates that 96% of the variation

maximum hue angle (h° = 108.39±0.33) was noted at

can be accounted for the change in a*. The colour

90 DAFS in the green region during the initial stage of

values b* (R 2 = 0.94) and L* (R 2 = 0.93) were also

fruit development. The maximum seasonal variation

strongly correlated with fruit development period.

was noted in colour parameter a* (CV = 189.99%) and

The R 2 values indicate that 94% and 93% variation

minimum seasonal variation was noted in L* (CV =

in data can be accounted by the change in b* or L*,

9.42%). Similarly, Alam-Eldein (2012) showed that

respectively. Similarly, the positive correlation was

peel colour index is an indicator of early changes, to

recorded in the chroma and fruit development. The

some extends and as such may be used as a quick

determination ratio was recorded R 2 = 0.97, which

and easy tool to determine the level of peel maturity.

accounted 97% variability in data. The negative

correlation was recorded between hue angle and

Relationship between fruit colour parameters (L*,

the fruit development, which implies that hue angle

a*, b*, C*, ho) and fruit development

decreased with the advancement of fruit maturity.

Regression equations for the prediction of fruit

The study suggests that fruit development correlated

maturity based on L*, a*, b*, chroma and hue values

with fruit peel colour and this may be useful for

are given in Figure 2. Studies revealed there exit

establishing harvest guidelines to avoid harvesting

strong correlations between colour space values (L*,

too early (immature fruit) or too late (senescent

a*, b*, C* and ho) with the fruit development period.

fruit) so that less postharvest injuries occur while the

Allȱofȱtheseȱchangesȱwereȱhighlyȱsignificantȱ(pȱ<ȱ0.05)ȱ

fruit still has acceptable quality (Sirisomboon and

andȱfruitȱmaturityȱhadȱeffectȱonȱcolourȱparameters.ȱ

Theamprateep, 2012).

Days after fruit set (DAFS)

Figure 2 Relationship between colour parameters (L*, a*, b*, C* and h°) and fruit development. R 2 indicates dynamic intensity.

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