Rapid analysis of table grape maturity based on color difference

摘要

Color of grape berry changed a lot during ripening that might reflect the maturity of table grape. In this study, the color difference of Kyoho grape skin was analyzed by CR-400 chroma meter, and the value of L*, a* and b* were measured at different stages of maturity. The results showed that the value of L* and b* decreased along with maturity, which reflected in the color of the grape skin turning darker and bluer. In addition, the value of a* increased continuously until 80% maturation and then decreased after this stage of ripeness. Results of correlation analysis showed that the value of L*, a*, b* and maturity were highly correlative (p < 0.01). Maturity was significant negatively related to L* and b*, and positively related to a*. There was negative correlation between a* and L*, b*, while significant positive relation between L* and b*.