Koro Kato

Exergy Evaluation in Grain Drying

In Japan, about 800,000 kl of fuel oil are consumed for drying farm products every year. Consequently, saving energy in the grain drying process has become an important agricultural problem. To reduce the energy consumed in grain drying and to establish a method of evaluating energy requirement based on exergy, theoretical and experimental studies were carried out. The energy supplied for grain drying is finally converted into the energy of grain moisture concentration difference, and is stored in grain. This energy is based on the difference in moisture content of grain compared with surroundings, and is released as heat of wetting when the moisture absorption occurs. In this study, we propose a method of exergy evaluation for grain drying, taking into account this energy of moisture concentration difference.

Prediction of Melon Fruits Softening Using Density and Transmitted Light

In Japan, external appearance quality inspection by image processing, and internal nondestructive quality inspection using near infrared spectroscopy and density have been put into practice for many agricultural products. For melons, external appearance of color and damage as well as sugar content are being inspected. As melons soften easily and are expensive, their softening or decaying during distribution would result in large financial losses. It is important, therefore, to predict keeping quality after shipment. Prediction of the optimum eating firmness by nondestructive inspection could bring a profit to consumers and distributors. In this study, the experiments were conducted in order to investigate the relationship between fruit density of melon and softening rate as well as the relationship between transmitted light level of melon and storage time. As a result, it became clear that there was a correlation between fruit density and softening rate measured by fruit pressure tester, and the softening rate of high-density melon was faster than that of low-density melon. Generally, the transmitted light level increases when the fruit soften. A high sensitivity camera took photographs using light transmitted through melons during the ripening and softening stages, and concurring results were documented. Therefore, the ripeness level at the time of shipment can be estimated using the transmitted light level, and the softening rate can be estimated using the fruit density measured nondestructively in packinghouse. By combining these methods, the time to reach optimum eating firmness after the shipment can be predicted.

New Electrical Method for Density Sorting of Spherical Fruits

A new electrical dry method for density sorting of spherical fruits, which measures the volume by electrical capacitance and mass by electronic balance, was proposed. A exact relation between the capacitance of concentric double spheres and the volume of the inner sphere was used for measuring the volume of spherical fruit. The accuracy of measured volume was very high. The new automatic and continuous density sorting system for sorting hollow heart and over-mature watermelons based on this study was developed and tested. A new packing house for sorting hollow watermelons using this dry method was constructed and operated successfully.

Moisture Distribution Image of Grain Layer Surface Using Multi-Wavelength near 970nm

Abstract In Japan because of high humidity, to preserve good quality of grain in silo, it is important to control not only the temperature but also the moisture. The purpose of this study is visualization of moisture distribution of grain layer surface using NIR image for rough rice. The 7 wavelengths near 970nm of water absorption band were selected. As the result, absorbance images of which average correlate with the moisture content were obtained for all the selected wavelengths and the difference image between the different wavelengths or image of secondary differentiation are being tried.