Assessment of the environmental impact of the cleaning stages of food manufacturing processes using Life Cycle Assessment: the example of milk protein separation via filtration

International audience ; Food manufacturing processes require frequent cleaning to assure the quality of the end product and tomaintain a faultless mode of operation of the equipment. However, the environmental impact of suchcleaning steps, which are known to consume large amounts of water, energy and chemicals, is rarelyassessed.The objective of this work therefore is to quantify the environmental impact of the cleaning stages of anindustrial food manufacturing process consisting of milk protein separation using Life Cycle Assessment(LCA) and to demonstrate the application of LCA for improvement of the process design.The inventory of the foreground system was established based on a collaborative project betweenseveral research institutes and industrial partners. Generic data was derived from the Ecoinvent V2.2data base and a comparative attributional Life Cycle Analysis (LCA) was carried out using IMPACT2002+ and the Simapro 8.0 software.The environmental impact of the cleaning stages corresponds to 31% of the impact of the entireprocess, compared to 65% for the production phase, 3% for the transport and 1% for the equipment. Toreduce the environmental burden of the cleaning stages two different strategies have been applied: (C1)reutilization of the process water from the reverse osmosis used for the concentration of the milkproteins as rinsing water and (C2) rationalization (i.e. less frequent renewal) of the cleaning solutions.Strategy C1 requires supplementary equipment for treatment of the permeate produced by the reverseosmosis thus generating an additional impact. Nonetheless, it allows a significant reduction of both thewater consumption by 316m3/day (583m3 milk treated/day) and the aquatic ecotoxicity impact of theentire process by 26%, mainly due to a lesser utilization of the potable water network. The secondstrategy (C2) decreases the environmental impact of the entire process by less than 10%. Bothstrategies could be implemented simultaneously thus leading to an even more considerableimprovement of ...