Abstract
To judge the degree of ripeness and the internal diseases of a pineapple, we developed a portable type internal quality evaluation device after a few basic experiments. It is based on the use of the amount of transmitted light originally from the sunlight. This method, however, had to make corrections on the transmitted light by the surrounding light since the irradiated sunlight is not constant. Furthermore, the light condition inside and outside the greenhouse is not identical, there had to be two types of indexes, one for the measurement inside the greenhouse and one for the outside to obtain ripeness and internal diseases from the corrected transmitted light. The new portable device consists of two parts; handheld measurement part of 600g which catches the transmitted light and surrounding light, and control part of 900g which valuates the ripeness and the internal diseases, both are small and light enough to carry around. The accuracy of ripeness evaluation was 80% as an appropriate evaluation. The evaluation of diseased fruit was possible by a single measurement for heavily damaged fruits but plural measurements was needed for medium damaged fruits. The trouble of not being able to detect the over-ripen fruits with light damages was also reported.
