Towards sustainable food systems in Belgium: production and consumption perspectives considering environmental impacts, nutritional values and dietary habits
Food production and consumption contribute largely to global environmental impacts. Protein sources play an important role in this, and research has shown that animal-based protein sources, such as meat and dairy, generally induce larger environmental impacts than plant-based protein sources, such as peas and legumes. At the same time, animal-based protein sources are suppliers of important nutrients. Therefore, when changing from animal-based to plant-based protein sources, it should be made sure that all important nutrients are still supplied. Furthermore, for changes to be actually adopted, they should be acceptable to consumers.
Several solutions have been proposed to lower environmental impacts of food, both from a production perspective and a consumption perspective. An important shortcoming of these solutions is that they consider general production systems and consumption patterns, while these vary between individual systems and consumers. This doctoral research explores a number of potential changes in Belgian production systems and consumption patterns of protein sources, taking into variabilities between farms and consumers, with the final aim to lower environmental impacts while ensuring nutritional needs and considering current dietary habits.
The first potential change relates to Belgian pig production systems. The influence of farm characteristics and feed compositions on the environmental impact of pig production was investigated. A main influencing characteristic was farm productivity, influenced by the feed conversion efficiency and sow productivity. In general, a higher productivity was related with lower environmental impacts. Other farm characteristics that influenced the environmental impact of the farms were the amount and type of energy sourcing and manure management. In terms of feed compositions, an important factor was the origin of soy ingredients, with land use change contributing largely to climate change impacts. Another important factor was the use of synthetic amino acids, which showed large contributions to environmental impacts of feed products.
The second potential change concerns replacing meat with meat substitutes. The environmental impact of producing a pork schnitzel was compared to the impact of producing a vegan and vegetarian soy schnitzel. Different functional units were considered to include the important functions of meat an meat replacers; that of meal component and that of supplier of high quality proteins. The pork schnitzel showed the largest environmental impact in terms of most environmental impact indicators. However, for some environmental impact indicators, the soy schnitzels showed higher impacts, especially if the protein content and protein quality of the products were considered. The environmental impact of the vegetarian soy schnitzel was higher than that of the vegan soy schnitzel, mainly because it contains chicken egg protein, which induces high environmental impacts. Other large contributors to the environmental impacts of the soy schnitzel were sunflower oil and the applied processes to produce the schnitzels. If protein quality is considered, the vegan soy schnitzel shows even lower environmental impacts than the vegetarian one, due to its slightly higher protein quality. It is thus environmentally and nutritionally more beneficial to replace the pork schnitzel with the vegan soy schnitzel than with the vegetarian one.
The third potential change relates to consumption patterns of protein sources. The goal was to formulate acceptable changes in protein source consumption patterns to lower environmental impact while supplying sufficient nutrients. Acceptability was addressed by limiting changes in current dietary habits of different consumer groups in the Belgian population. Therefore, in a first step, different “protein consumption typologies” were identified: consumer groups with different consumption frequencies of different protein sources. In a second step, an optimization model was composed, in which the environmental impact of protein source consumption was minimized while ensuring nutritional adequacies. Changes in the current consumption patterns of the identified typologies were limited to ensure acceptability of the proposed changes. The model results showed that changes of maximally 50% in the current consumption of protein sources can lead to considerable reductions in climate change impacts while adhering to nutritional recommendations. The changes mainly involved reducing the consumption of meat products and increasing the consumption of eggs, milk products and plant-based protein sources. The changes differed between the typologies, leading to more personalized dietary advices than nationwide advices.
The proposed changes could together lead to more sustainable Belgian food systems, with changes in consumption patterns having the largest potential for environmental impact reductions. In order for the changes to be actually adopted, they should be embedded in the broader sense of food systems, including social and economic parameters.