Hot or cold? The choice of whether to perform separation at high or low temperatures is a critical one for dairy operators.
Hot milk separation is the more widely used application as it offers improved separation efficiency and higher capacity for production lines. But cold milk separation using high-quality equipment offers several compelling advantages.
Separation at cold temperatures minimizes bacterial growth. It also allows for longer run times between cleaning in place.
Cold milk separation is commonly used outside high-temperature short-time (HTST) processing to avoid double heating the milk.
“Cold milk separation can be a very good alternative,” says Johan Friis, project manager key components. “Bacterial growth in the line is lower at a low temperature and you also save energy costs because heating up fluid is expensive. Heat also impacts on the proteins in the milk. Less heat impact on the proteins in the milk is always favourable.”
One of the major advantages, Friis explains, is long production running times. “Normally the capacity is lower compared to hot milk separation. But you can run for much longer without having to clean the equipment and that reduces your total cost.”
It is generally often necessary to clean a cold separation line only once a day, but running hot it requires the wet part of the line to be cleaned more often. Cleaning is a time-consuming process that requires production downtime.
Tetra Pak AirTight separator design is an ideal choice for cold milk separation. Unlike many separators, AirTight separators are closed, which allows separation to be performed more efficiently at a lower temperature.