Efficacy of a pilot-scale ultrasonication system for pasteurization of milk

Abstract

This study aimed to test a pilot-scale continuous ultrasonication (US) system to pasteurize whole milk in terms of physical properties, energy consumption, and inactivation of alkaline phosphatase (ALP), total mesophilic aerobic bacteria (TMAB), total coliform (TC), total enterobactericeae (TE), and Escherichia coli. Except for those treated by 90% amplitude for 20 and 30 min, the samples were found negative for ALP activity. Inactivation of TC, TMAB, TE, and E. coli rose with an increased amplitude and temperature. The maximum cost was estimated at 2.778,00 € for the system and at 3.624,00 € for plate heat exchanger to pasteurize 20.000 L of milk. 96.52% amplitude, 40 min, and 53.50 °C were determined jointly as the optimal operational settings.