Dubravka Skunca, LCA (Life Cycle Assessment) Leader in the GreenProtein Project, has produced an LCA to assess the environmental performance of the system of RuBisCO protein extraction and isolation from sugar beet leaves.
What is exactly a Life Cycle Assessment?
LCA is an analysis technique to assess environmental impacts associated with a product system throughout its life cycle, which includes raw material extraction, materials processing, manufacture, distribution and use.
Key ideas to understand the GreenProtein LCA
On the one hand, RuBisCO is a protein in green leaves of plants that contains high amounts of essential amino acids (great for food applications!) and is considered the most abundant protein present on earth. That is, it is possible to extract RuBisCO from many plants and crops with green leaves, for example: alfalfa, yellow mustard, ryegrass (mixture), Italian ryegrass, Brussels sprouts, English ryegrass, carrot leaves, leaf radish or chicory.
On the other hand, besides plants there are other raw materials (animal proteins like egg whites for example) from which it is also possible to extract high quality proteins (different to RuBisCO).
When extracting RuBisCO, what are the raw materials that have the lowest environmental impact? What processes are the most environmentally friendly? The GreenProtein RuBisCO extraction process from sugar beet leaves less or more environmentally friendly than extraction from other crops? How could the extraction and isolation processes exactly affect the environment?
Those are some of the questions the LCA tackles!
What has the study done?
The study has carried out various calculations and analysis to identify and quantify the environmental impact of the RuBisCO protein extraction and isolation from sugar beet leaves in comparison to other crops and protein sources. These include:
- Calculations that covered seven subsystems for the extraction and isolation of RuBisCO: milling and extraction, heat treatment, centrifugation, microfiltration, ultrafiltration, chromatography and spray drying.
- Six environmental impact categories were analysed: global warming potential, ozone layer depletion, energy demand, eutrophication potential, acidification potential and land use.
What were the results of the LCA?
The results of the study are the following:
- When RuBisCO protein extraction and isolation from different raw materials is compared, the only crop that has lower environmental impact than sugar beet leaves is alfalfa. Crops with a higher environmental impact are yellow mustard, ryegrass (mixture), Italian ryegrass, Brussels sprouts, English ryegrass, carrot leaves, leaf radish and chicory (last one is the one with the highest environmental impact).
- Mircoalgae: results for RuBisCO were in accordance with the low end of the range of results for microalgae, which is representing Chlorella HTF (heterotrophic fermenter), for most of the analysed impact categories.
- Highly functional plant proteins: direct comparison was not possible as these are not in the market or have no LCA data available.
- Egg protein concentrate: the comparison of environmental impact categories of different protein concentrates indicated that protein powder containing RuBisCO affected environment less than egg protein concentrate.