Energy Consumption in the Processing of Dairy and Feed Powders by Evaporation and Drying

Vacuum concentration and drying are valuable techniques for the removal of water and the resulting stabilization of most dairy and feed ingredients. In this study, we present methodology to calculate and compare the energy consumption for the production of dairy and feed powders at different processing stages of the dehydration process. The results show that the energy costs to produce 1kg of dairy and feed powders were 6,120 and 20,232kJkg(-1) powder for pregelatinized starch and soy protein concentrate, respectively. For dairy products, the values were 9,072 and 15,120kJkg(-1) for fat-filled and demineralized whey powders, respectively. According to the type of product (biochemical composition, ratio of bound and free water) and process (demineralization, vacuum evaporation, lactose crystallization, roller and spray drying), the energy consumption for the production of powders could be calculated. These findings could be valuable for studies focusing on improvement of energy efficiency for dairy and feed processes.