Dairy products are responsible for 8 to 10% of environmental impacts of European consumption (Weidema et al. 2009). Businesses have to respond to an increasing pressure for higher quality products, while still maintaining competitive prices.
This study analyses the application of Ultra-high pressure Homogenisation (UHPH), an innovative technology for food sterilisation that relies on pressure up to 400MPa, for the treatment of cow milk. The technology is forseen to provide equal or higher quality products compared to the combination of Ultra High Temperature (UHT) and Homogenisation treatment and, at the same time, to lower energy consumptions through the combination of sterilisation and homogenisation in a single process. Furthermore, the use of UHPH treated milk for the production of fresh cheese has been proven to increase shelf life from ~13 to ~19 days and yield from 11 to 14% (Escobar 2011; Zamora and Guamis 2014). This study provides an LCA of UHPH and UHT processing of milk and fresh cheese production from processing to end-of-life.
Pilot scale data was collected for the following cases: UHPH equipment with capacity of 90l/h was tested with water, buffer, skimmed milk (1.5%) and whole milk (3.5%); UHPH with capacity of 360l/h with water; and an 85l/h indirect UHT system, including upstream homogenisation, tested with water. As the first case showed no difference in energy consumption for the four compounds, only water was used for the following tests.
UHPH is a technology not yet used industrially, power-law relationships were used to model the relationship between the equipment’s main variables, such as capacity and energy use, as scale increases.
The results of this study show that UHPH is more environmentally beneficial at pilot scale due to lower water and energy consumptions. Savings of approximately 14% are predicted for electricity alone. However, at industrial scale UHT systems ensure an energy recovery of approximately 90%, which is hardly achieveble with UHPH at current technology development level. On the other hand UHPH has a potential of reaching at least 43% of energy savings and carbon dioxide emission reduction; and further resuctions are possible with a long term perspective. Moreover higer quality milk could result from UHPH treatment. Up scaling of UHPH showed the increase in efficiency for different pilot scale and confirmed the linear relatiosnhip between energy use, capacity and speed for UHPH homogenisers. The increase in shelf life of fresh cheese produced from UHPH milk will bring benefits at larger scale due to reduction in food waste and resource use.