Alternative protein sources

Experts: Edouard Appenzeller (SGLWT), Marc Lutz (SGLWT), Erich Windhab (ETH Zürich/SATW)

Plants, insects and cell cultures are the protein sources of the future. Meat cannot satisfy the rapidly growing global demand for proteins – moreover, the meat industry places a heavy burden on the environment. Hence the intensive research into alternative sources of protein being carried out worldwide. If Switzerland wants to remain innovative in this area, ETH Zurich, universities of applied sciences, other universities and industry must tackle the big issues together.

Picture: Shelley, Unsplash

Definition

Many consumers seek products that look and taste like meat or fish, but are not derived from animals. Alternative proteins come from four different sources: plants containing protein, laboratory-grown in-vitro meat, micro-organisms and insects.

Current and future applications

The first group comprises plants that contain protein, such as legumes, grains, nuts and oilseeds. The proteins obtained from them can be processed to make products that are substitutes for meat, cheese or milk. For this purpose, traditional processing methods are used, like coagulation, which is required to produce tofu. Newer processes are also applied though, such as the extraction and structuring of plant proteins. Replicating the fibrous structure of meat is still challenging. In the future, innovations in process engineering, e.g. 3D printing, should enable better imitation of flesh’s fibre-based structure.

Secondly, there is the field of laboratory-grown in-vitro meat. This is based on stem cells taken from an animal, such as a beef cow, under anaesthesia. These stem cells are then used to grow differentiated cells in a nutrient solution under sterile conditions in the laboratory. Whereas it cost 250,000 Swiss francs in 2013 to produce the first burger made in this way it now only costs around 10 Swiss francs – although this is still far higher than the market will tolerate. Whether a market-compatible price can ever be achieved is debatable. However, the fall in cost does show how much progress has already been made in refining these methods. As yet, the methods work at laboratory scale. Scaling up in-vitro meat production still requires a lot of real-world-centred research though, because the products are still far too expensive to survive on the mass market and only viable in the premium segment.

The third group of alternative protein sources consists of proteins that are either obtained from micro-organisms like fungi (e.g. yeasts and microalgae) or produced by micro-organisms. Quorn, based on a protein obtained from the mycelium of a sac fungus, has been on the market for 40 years. Nevertheless, such proteins are niche products. At present, their primary use is in animal feed rather than human nutrition. In the future, these alternative proteins could replace feedstuffs like soy meal and fish meal.

The fourth group comprises proteins obtained from insects. In industrialised countries, these are also mainly processed to make animal feed and have not yet been able to establish themselves as food for humans. At present, there is no widespread public acceptance of insects for human nutrition. The current regulatory provisions hinder sustainable production, as feeds currently have to consist of high-quality resources that can also be directly consumed by people.

Not only are proteins an indispensable part of human and animal nutrition, they also have properties that are used in food-processing methods at home or in industry. For instance, proteins can be foamed and, as emulsifiers, have the ability to bind fat and water.

Opportunities and challenges

Authorisation regulations constitute a major hurdle when it comes to establishing new and innovative foods. An extensive application dossier has to be submitted to the relevant authorities to obtain approval of so-called ‘novel food products’. The procedure is expensive and time-consuming, and involves risks for applicants. It is therefore to be feared that many products will establish themselves in other markets first, and only belatedly be approved in Switzerland and the EU. If Switzerland is to play a role as a centre innovative research, appropriate framework conditions must be set up.

Much like insect farming, it is likely that the resources for producing cultured meat will have to meet strict purity criteria, making culturing expensive and energy-intensive.

The bioreactors currently available for growing in-vitro meat need to be improved. For one thing, the number of cells per unit area, i.e. the cell density, must be increased. As a piece of meat comprises multiple cell types and follows a chronological and hierarchical structure, procedures must be developed that allow different cell types to grow or to be combined with each other. Ways of doing this, for instance using scaffolds, are currently being researched. The production of in-vitro meat has benefited greatly from medical tissue engineering, i.e. the production of tissues for specific purposes. Conversely, food technology’s advances in the cultivation of meat cells could also enrich medicine. The food industry and medicine could thus benefit from each other. For a long time, Switzerland was a leader in the manufacturing of bioreactors. Today though, a large proportion of these devices are made in China or Korea. Switzerland could regain its former position in the development and production of such devices if it were to successfully establish an interdisciplinary dialogue between biologists, food scientists, medical technicians and process engineers.

Funding

The development of alternative protein sources cannot be considered in isolation, as it is embedded in the food supply chain. This can only be made more ecological and, in a broader sense, more sustainable if the various players, the universities of applied sciences, other universities and industry, tackle the big issues together. One approach that could make sense here would be for the involved parties to focus on their respective roles,with ETH Zurich concentrating on knowledge of systems, and the universities of applied sciences generating knowledge of problems and working on corresponding solutions, which are then put to use by industry. However, this requires a common culture and mutual trust, which are only present in rudimentary form today.

The regulations constitute another obstacle to the research and development of alternative protein sources. Currently, companies need authorisation to market-test their products. Procedures such as tastings and panels are only possible for authorised foods. Authorisation of limited tastings could provide a remedy. After all, companies do not invest in new products if they do not know whether they will survive on the market.

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