Prediction of the onset of climacteric fruit ripening based on fruit growth characteristics

Appearance, texture, flavour and aroma of fruit undergo major changes during ripening. These changes normally start when the fruit is mature and reaches its nearly full size. However, predicting the exact moment when these quality changes are triggered is challenging. In this study, we present a generic approach to predict the onset of climacteric ripening based on a ripening activation function that incorporates the derivative of mass change of the fruit. We show that the parameterisation of the presented model depends on species but is universal for different growth conditions with different fruit growth dynamics. The proposed model was tested on four different fruit: tomato and kiwifruit representing berries; apple and pear representing pome fruit. The ripening identification model allows the integration of models describing various quality attributes with a growth model – enabling to prediction of a whole set of traits in one model rather than focusing on yield and selected quality attributes separately.