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The environmental impact of seaweed/algae as novel feed ingredient in the diet of farm animals - Eva Buis

The livestock sector is in urgent need for more environmental friendly feed sources. A promising novel protein source are algae or seaweed. The goal of this study was to explore the environmental impact of S. Platensis (algae) and U. Lactuca (seaweed) as novel feed ingredient in diet of livestock, by making use of a Life Cycle Assessment (LCA).

With a growing and wealthier world population the demand for animal source food will be doubled in 2050. However the livestock sector already has a high impact on the environment mainly from the production of livestock feed. Therefore the livestock sector is in urgent need for more environmental friendly feed sources. A promising novel protein source are algae or seaweed, mainly due to its multi-functionality, e.g. protein for feed, oil for biofuel and ash for fertilizer.

The goal of this study was to explore the environmental impact of S. Platensis (algae) and U. Lactuca (seaweed) as novel feed ingredient in diet of livestock, by making use of a Life Cycle Assessment (LCA). Assessed by considering Global Warming Potential (GWP), land use (LU) and energy use (EU). The species were chosen based on their protein content, possibility for large scale production, high growth rate and low or no toxicity. Mass- and economic allocation were used to divide the environmental impact between the different multifunctional products.

Based on mass allocation S. Platensis has a 7 times higher GWP compared with soybean meal and a 14 times higher EU, mainly due to the drying step. LU was 96.3% lower. U. Lactuca has a 2.5 times higher GWP, a 5.1 times higher EU, and a 99.5% lower LU compared with soybean meal. Based on economic allocation an 8 times higher GWP and a 15 times higher EU was found compared to soybean meal and LU was 96.2% lower, due to the high yield of the algae. U. Lactuca has a 55.1% lower GWP, a 7.3% lower EU and a 99% lower LU compared with soybean meal. Also for seaweed the drying step is the largest contributor to GWP and EU. With the used production process, S. Platensis has a higher environmental impact compared with conventional protein resources.

Based on the economic allocation, U. Lactuca has the potential to replace conventional protein resources. Based on the mass allocation, conventional protein resources have a lower environmental impact than seaweed. The drying process as well as the biorefinery process has to be optimized before conventional protein resources can be replaced by seaweed (U. Lactuca).

Student: EAM Buis

Supervisor: H van Zanten, MSc

36 Ects