Evaluation of pomelo maturity based on acoustic response and peel properties

Summary This research investigated the maturity assessment of pomelo using acoustic properties obtained from an impact of fruit, optical properties of the peel and variables related to oil glands from peel images. Pomelo samples were harvested at 5.5, 6.0, 6.5 and 7.0 months after anthesis. All nondestructive variables were used to build qualitative models with partial least squares discriminant analysis. The classification model based on the nondestructive variables showed that fruits could be separated into immature, early-mature and late-mature groups with an accuracy of 96.7%. The important variables contributing to the classification were the impact response based on the second-order resonant frequency and the difference of green colour between the oil gland and the peel.