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Description
Pomelo is a tropical fruit that is widely cultivated in Thailand. The price is largely varied according to cultivars. Certain qualities can be observed from fruit exocarp but for fruit sweetness or sourness it is impossible to externally determine. In this work, we explore the relation between the electrical capacitance and the fruit pericarp using a parallel-plate system for four frequencies, 2, 10, 50, and 100 kHz. Fifteen pomelos are measured for their capacitance, weight, and physical dimensions. The same measurements are repeated for all samples without their exocarp and mesocarp. The results show that the capacitance decreases when exocarp and mesocarp are removed. The decrement is due to the loss of water molecules residing in the pericarp. As a consequence, its permittivity declines. The ratio of capacitance to fruit mass displays variation that is possibly related to soluble solid and chemicals in the fruit.
