Hot and Cold Milk/ Pasteurization
Separators have been used in the production of milk for more than a century. As milk varieties expand, the need for more sophisticated separators also has grown, with processors separating and reintroducing milk fat for different fat-based product types. During the separation process, a separator’s motor –driven centrifuge rapidly spins raw milk in order to remove heavier milk solids from the rest of the fluid and to separates the cream from the skim milk.
For fluid milk, milk fat can be gradually added back in at various levels to make whole milk, 2%, 1%, and other such varieties. Separators are also used in the cheese production for whey, a byproduct of the cheese making process. Cheese fines can be removed from whey through a centrifuge clarifier, with additional fat removed in a whey separator.
Plants that manufacture dairy-based powders also utilize separators, to take out milk proteins during drying process. Lactose, whey protein, casein and butter oil can all be recovered through the use of separation technology. On the quality and food-safety side separators have been used for clarification purposes to help bacteria. Separator sizes and types vary. While the basic engineering of a separator hasn’t varied much in the past few decades, some separators are larger today to accommodate growing capacity demands- up to 150,000 pounds an hour- while several are built with automatic software-based control system.
Separators are available as mostly as non-heretic centrifuges, which feature a natural setting action during the spinning process, and in some cases, as disc stack centrifuge. Separators are powered by motors that range in speed, while some separators include internal pumps for liquid removal. Separators can also be adjusted for either hot-milk or cold-milk processing. During hot milk separation, with temperatures ranging form 120 to 145 degrees F, a separator is used to separate the globular milk fat from the skim milk or serum, with the outgoing common but can be done with cold milk separators, which tend to have special design features and lower capacities than hot milk or warm milk models. Also the cream separator can be connected to a standard HTST pasteurizer in the regeneration section.
Conventional centrifuges are the types most commonly used in many applications- these are “open style” non-hermetic centrifuges and may have internal pumps for liquid removal or may discharge by gravity to atmosphere. Some common beverage applications include fruit juice, pulp reduction orange juice, wine, beer, coffee clarification.