UNIT PROCESS ENERGY REQUIREMENTS FOR STEAM INFUSION UHT MILK PROCESSING.

A steam infusion ultra-high temperature (UHT) system was used to sterilize raw milk at 138, 143, 148, and 154 degree C. Energy consumption/recovery of various unit operations of the UHT system and a conventional high-temperature-short-time (HTST) pasteurization system were determined and compared. The UHT system consumed between 476 and 570 kJ/kg milk. The HTST system, in comparison, consumed between 120 and 131 kJ/kg milk. The HTST system, in comparison, consumed between 120 and 131 kJ/kg milk. The energy consumption/recovery of the regenerator, preheater (heater), homogenizer, and cooler were comparable for both systems. The sterilizer utilized between 71 and 74% of the total energy required by the UHT system. Heat absorbed by the vacuum chamber vapor condensing water, between 243 and 311 kJ/kg milk, represents the heat recovery potential for the steam infusion UHT system.