Evaluating internal disorder of mango by underwater ultrasound.
Hurng HuaangYouh, Ay Cheng, Lu FuMing
ASAE Paper No. 006112
2000 ASAE Annual International Meeting, Milwaukee, Wisconsin, USA, 9-12 July 2000 : 1-15
Abstract : Mango fruit cv. Chiin Hwang often has physiological disorders during maturing or postharvest. The fruit with a physiological disorder has a good integrated appearance but the inner fruit is of bad quality, such as a rotten and loose texture, and the outside of fruit has brown colour or is cracked. Farmers detect the physiological disorder using a traditional method by specific gravity. The internal quality and physiological disorder of mango was investigated using a nondestructive technology. A low frequency (0.5 MHz) ultrasonic transducer was used and placed under water to transmit and receive ultrasound by a pulse echo method. The ultrasonic signal transmitted through the fruit sample and was displayed on a digital oscilloscope. The internal texture changes of fruit can be evaluated by the ultrasonic signal changes. The results showed that ultrasonic attenuation could be observed and calculated by signal display of the wave pattern on oscilloscope. The amplitude of sound wave was directly proportional to the sound pressure. The peak differences of continuous wave express the energy absorption by mango. The relationship between the ultrasonic attenuation and internal quality and ripening of the Chiin Hwang mango was obtained in this study.