MODELING AND TESTING OF ULTRASONICATION BASED BACTERIAL DEACTIVATION DEVICE

• Main Author: Wangi Arraudah Baliwangi, Sekar
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/50155
• Institution: Institut Teknologi Bandung

Currently, the most frequent method used for inactivation of bacteria in food involves heat treatment. The use of high temperatures in food processing may have a negative impact on food’s nutrition and quality. One of the alternative methods being developed to reduce this impact is ultrasonication method. This method uses ultrasonic waves to produce cavitation bubbles, which could have a destructive effect on bacterial cell walls. Modeling and testing were carried out in this study to give the number of deactivated bacterial colonies due to the effect of ultrasonication. Cavitation bubble dynamic based on Rayleigh-Plesset equation and pressure propagation during collapse modeling, was performed using the Euler method in the MATLAB software. The result of pressure propagation modeling can be used to predict the number of bacterial colonies reduction. Whilst, the test was carried out by the probe ultrsonicator on B. subtilis and E. coli bacteria. The number of deactivated bacteria based on modeling and testing will then be compared. By comparison of the two results, it was found that the number of deactivated bacteria from modeling (1.133.000 CFU/ml) was less than the number of tested bacteria (2.832.200 CFU/ml). This was caused by the simplification and assumptions used in the modelling. At the end of the study, the calculation of bubble density based on the number of deactivated bacteria from the test data was also carried out.