Abstract:
The relationship between total solid contents and red, green, blue (RGB) colour intensity of full
spectrum images of strawberry fruits were examined to develop an efficient, non destructive,
cost effective and economical method to determine correct maturity stage of strawberry fruits
for harvesting. The RGB colour intensity of the full spectrum images of strawberry fruits
of cv. Chandler, RGB colour ratio and their respective total solid content (Brix value) at
three different colour development stages; fully red coloured (FRC), three-quarter coloured
(TQC) and half coloured (HC) were analyzed. Total solid contents of the strawberry fruits
were significantly difference among the three colour developmental stages of fruits. The highest
average total solid contents (7.7 0
Brix ) was found in the fully red coloured strawberry fruits
while the lowest total solid content (5.3 0
Brix ) was found in the half coloured fruits. Total solid
content of three-quarter coloured fruits was 6.1 0
Brix. The sum of red, green and blue colour
(R+G+B) intensities and the ratio of ((G+B-R)/(R+B+G))2
were strongly correlated (R2
=0.95
and 0.89 respectively) with the total solid content of strawberry fruits. This two indices could
be used to decide the correct maturity stage of the strawberry fruits. With reducing the values
of these indices, increase the TSS of fruits. consequently, the lowest values of indices indicates
the highest total solid contents in fruits .
