Environmental impact of four meals with different protein sources: Case studies in Spain and Sweden

The production of food protein has a considerable impact on the environment. This paper investigates the potential environmental benefits of introducing more grain legumes in human nutrition. Four meals with different amounts of soybeans or peas (either used as feed for production of pork or directly consumed) were analysed using life cycle assessment methodology. The results of this analysis demonstrate that it is environmentally favourable to replace meat with peas. In particular, the addition of more legumes to human nutrition potentially aids in the reduction of global warming, eutrophication, acidification, and land use; however, in terms of energy use, a completely vegetarian pea burger meal requires the same amount of energy as other meat-containing meals. Feeding pigs with European-produced peas instead of imported soybeans, in addition to partial replacement (10%) of meat protein with pea protein, failed to reduce the environmental impact of the meal. In summary, peas can be considered ‘green’, but there remains a significant need for more energy-efficient processing of vegetarian products.