The processes for the production of anhydrous milkfat (butter oil), using cream as the raw material, are based on the emulsion splitting principle. In brief, the processes consist of the cream first being concentrated and the fat globules then being broken down mechanically, so that the fat is liberated. This forms a continuous fat phase containing dispersed water droplets which can be separated from the fat phase.
Either the Clarifixator or the Centrifixator is used for mechanically liberating the fat and thus allowing for the phase conversion, and these two process lines derive their names from the corresponding units.
The Clarifixator line has been used commercially for a number of years. One of the key machines in the system - the Clarifixator - is a centrifugal separator equipped with a serrated disc which simultaneously homogenizes the milk. The disc normally breaks down the fat globules into smaller globules, although in the production of anhydrous milk fat, the disc breaks down the emulsion, so that the liquid leaving the machine is a continuous oil phase, with dispersed water droplets and buttermilk. After phase inversion, the fat is concentrated in a hermetic separator. Clarifixator lines with capacities between 500 and 1000 kg of butter oil per hour are available.
The Centrifixator line has an appreciably higher capacity of 1500 - 2000 kg of butter oil per hour and offers opportunities for planning production rates of 4000 - 6000 kg of butter oil per hour. In this case, the emulsion is split in a unit of special design - known as the Centrifixator - which contains a motor-driven serrated disc. The fat is concentrated in a hermetic solids-ejecting separator. Solids-ejecting machines are also used in the second centrifugal separation stage, and the line is thus capable of operating for long periods and can be cleaned in place.