Evaporators are units where the solid content of liquid foods are increased by the rapid evaporation of water ocntent of the milk. It is widely used in Dairy Industry; mainly for Yoghurt Processing, Condensed Milk Processing, Sweetened Condensed Milk Processing and Whey/Milk Powder Processing.
There are 2 main types of Evaporators; Falling Film and Rising Film. Falling Film Evaporators arepreferred in Dairy Industry as milk can tend to form foams during processing.
However, increasing the solid content of foods doesn’t effect the microbial activity of milk; maybe it even causes that to increase. So the evaporated/concentrated product has to be heated/sterilised on further process.
Vacuum evaporators are commonly adopted since it is economical method of concentration. Use of multiple effect vacuum condensing plant is used for the purpose and use of high vacuum (i.e. 29 inches of Hg column) helps in evaporating water from mil kor juice at much lower (i.e. 58-60 0C) than its boiling temperature with steam economy too.
