Reduction in water and energy consumption in dairy processes

The dairy industry is an important sector in the food industry with sales of 124.3 billion euros and an added value of 17.4 billion euros. It has high energy and water consumption, both in overall production and per unit produced: up to 6.47 MWh (5.55 MWhth and 0.92 MWhel) and 60 m3 of water per tonne of transformed milk. A total of 98% of the freshwater that is used is drinking water and 80% of the energy is consumed in the operations of heating, pasteurisation, sterilisation, drying and cleaning.

The EnReMilk project has achieved savings of up to 20% in energy and 30% in water throughout the entire supply chain in two representative cases in the milk industry: the production of mozzarella and the production of powdered milk.

Initially, patterns of water and energy consumption were identified throughout the respective processing chains. In a second step, through monitoring and real-time management techniques to reduce the consumption of water and energy, these processes were modelled (that is, technological scenarios were established to identify potential savings) and microbial stabilisation techniques, heating, texturisation and drying were applied. The resulting parameters were assessed to establish the resource use strategy, the treatment of effluent from the process and the technologies of water reuse to ensure the quality and safety of the food. The results have been validated in pilot tests under industrial conditions during a three-month period.

The project, which is part of 7PM, received 5.1 million euros of funding and lasted 4 years. The consortium, which is led by the Fraunhofer Institute for Interfacial Engineering and Biotechnology, was formed by 15 members from 6 countries, including the specific research centre CS2AC, which was responsible for monitoring tasks and real-time management to minimise water and energy consumption.