Modifications on the Processing Parameters of Traditional Pineapple Slices by Stabilized Sound Pressure of Multiple Frequency Ultrasonic-Assisted Osmotic Dehydration

Abstract

This study investigated the practical feasibility of synergistically and optimally applying ultrasound-assisted osmotic dehydration (UAOD) practices for the pineapple slice picking process (in sugar osmotic solution), with potential implications for improving current practices. This study was carried out to evaluate the effects of different treatment conditions of single (40 and 80 kHz)/multiple (40/80 kHz) frequencies, output powers (300, 450, and 600 W), and treatment time (5–40 min) at 30, 45, and 60 °Brix applied, respectively, on the pineapple slices picking process. The sound pressure of the UA was also measured to confirm that it provided the corresponding effect stably under different conditions. The ideal UAOD operating condition for pineapple slices is a 45 °Brix sugar osmotic solution, with frequency multiplexing at 40/80 kHz and an output power of 450 W for 25 min, which yields the optimal solids gain (SG) rate of 7.58%. The above results of this study indicated that UAOD could improve the accelerated quality transfer of pineapple slices and enhance the final product quality, thereby increasing the efficiency of the dehydration process and saving processing costs and time.