Effectiveness of milk soil removal in a bath-substrate-flow (BSF) device for different types of milk

• The temperature rise increases the detergency.
• Higher pH values increase detergency.
• For similar conditions, increasing surfactant concentration enhances detergency.

The effectiveness of the removal process of milk soil was studied using a laboratory device called bath-substrate-flow and three different types of milk: sheep, skimmed cow, and milk for infants. Experiments were performed using different surfactants and operation conditions. The washing efficiency was related to the temperature of the process, type of soiling agent and wash-bath composition. The highest detergency in all cases was detected at high pH levels with surfactants. The results show that the cleaning of these soils differed for each type of milk and depended on the composition of the residue formed. The use of specific surfactant formulations for each soiling agent under the appropriate conditions proved to be a useful option to reduce the cleaning times for clean-in-place processes of milk foulants in the dairy industry, guaranteeing cleaning with a lower environmental and economic impact over the final products.