earth
PSF-R32

How to share environmental impacts between milk-derived coproducts?

Food is a significant contributor to humans’ environmental impacts and appropriate metrics to quantify them is essential to take and follow mitigation actions. Industrial processing accounts for less than 5% of the overall impacts of food systems but is central to sustainability. While agricultural production of commodities like milk generates over 75% of the food’s environmental impacts, processing prevents food waste and food spoilage to the expense of energy and water resources. However, industrial processes often involve separation of the commodity into coproducts, among which these environmental impacts must be shared.

  In the present study, STLO and SayFood investigated different approaches to share the environmental impacts of milk processing between 5 coproducts: cream, casein, lactose and two whey-protein fractions enriched in α-lactalbumin or β-lactoglobulin. The life cycle assessment (LCA) method was followed but varied in using a synoptic or “black box” description of the factory and in using different allocation rules.

  • A synoptic description of the processing cascade makes it possible to subdivide the system and thus to attribute the impacts of each operation unit only to the relevant coproducts. On the contrary, a “black box” approach will irrelevantly attribute a share of the impacts of drying milk proteins to lactose or cream.
  • The allocation rule also has a significant influence on the respective share of impacts attributed to each coproduct. For instance, the cream can receive from 8 to 48% of the total impacts depending on the mass, dry matter, protein or economic allocation rule.
  • Milk production, energy and cleaning products contribute most to the overall environmental impacts.
  • Concentration, spray-drying and cleaning are operational hotspots, respectively due to energy expenses and water pollution.

 

milk fractionation sytem
The milk fractionation system assessed in this study

This study contributes to reaching a consensus on how the life cycle assessment method can relevantly evaluate the environmental burden of foodstuff. By using data obtained at the industrial scale, it also provides professionals with benchmarks for the ecodesign of dairy processes.

Collaboration

This work was funded by the French National Research Agency (ANR) under the grant ANR-19-DATA-0016 “Structuring and opening data to improve sustainability of food systems” (DataSusFood). It reused data collected during a previous project also funded by the ANR under the grant ANR-06-PNRA-015 “Eco-design of membrane processes for obtaining proteins with target function(s)” (ECOPROM).

Read more

Guyomarc’h, F., Héquet, F., Le Féon, S., Leconte, N., Garnier-Lambrouin, F., Auberger, J., Malnoë, C., Pénicaud, C., & Gésan-Guiziou, G. (2024). Life cycle assessment to quantify the environmental performance of multi-products food processing systems such as milk fractionation: Importance of subdivision and allocation. Journal of Food Engineering, 380, 112147. https://doi.org/10.1016/j.jfoodeng.2024.112147

Guyomarc’h, F., Héquet, F., Le Féon, S., Leconte, N., Garnier-Lambrouin, F., Auberger, J., Malnoë, C., Pénicaud, C., & Gésan-Guiziou, G. (2024). Life cycle inventory and life cycle impact assessment datasets of an industrial-scale milk fractionation process generating 5 co-products: Cream, casein, lactose and two whey-protein ingredients enriched in α-lactalbumin or β-lactoglobulin. Data in Brief, 55, 110676. https://doi.org/10.1016/j.dib.2024.110676

 

Contacts

Genevieve.gesan-guiziou@inrae.fr

fanny.guyomarc-h@inrae.fr

caroline.penicaud@inrae.fr