Kajian Sifat Akustik Gelombang Ultrasonik Sebagai Identifikasi Mutu Non Destruktif pada Tiga Jenis Manggis

Abstract

Mangosteen (Garcinia mangostana L) fruits grade one with diameter 55-65 mm from three locations (Bogor, Purwakarta, and Sukabumi) were stored at the room temperature. The objectives of this research are to identify quality degradation of three types of mangosteen by analyzing of the acoustic character of ultrasonic wave. As results, quality degradation was found significantly at 9th day of storage period when increasing of color value (brightness) and the firmness occur simultaneously with decreasing of the value of total soluble solids. On the maturity process of mangosteens, ultrasonic velocity and total soluble solids increased while attenuation and the value of firmness decreased. Range values of wave velocity are transmitted in the sample group mangosteen Bogor, Purwakarta, and Sukabumi respectively 221.60-282.15 m/s, 243.27-334.54 m/s, and 214.36- 244.10 m/s. Range attenuation coefficient values for the sample group mangosteen Bogor, Purwakarta, and Sukabumi respectively 19.98-25.17 dB/m, 15.46-24.04 dB/m, and 13.97-22.30 dB/m.