The concentration process consists in the evaporation of a liquid product, with high moisture content, under vacuum conditions (pressure below atmospheric pressure). The objective is to remove the water contained in the liquid to be processed at a temperature below 100°C. The source of thermal energy can be pressurized steam or steam subjected to atmospheric pressure, originating from the cooking and/or drying process. The system can be used for stickwater (water with a large amount of soluble protein) originating from the low temperature process, to concentrate the stickwater from the hydrolyzed feather meal pressing and to concentrate the clotted blood serum. The most used Concentrators in our processes are the Falling Film type Evaporator, for fat free stickwater, and Slurry type Evaporators, to evaporate raw material with fat. The concentrators can have multiple stages with the objective of optimizing the initial energy required for evaporation.