Alternative protein feeds comprise raw materials used as an alternative to typical concentrated feed bases such as maize, soya and wheat for the feeding of farm animals.
The basic idea of alternative protein feeds is to produce and import less protein feed such as soya worldwide. Today, about half of the protein crops grown globally such as soya end up as concentrated feed in the troughs of chicken, pigs and cattle that are bred for maximum performance. The production of this protein-rich fodder is accompanied by the expansion of agro-industrial areas, the over-fertilization of agro-ecosystems and the greenhouse gas emissions caused by land-use changes, the deforestation of large areas of land and the loss of biodiversity. By reducing soya imports, the land earmarked for feed production could be used for the cultivation of food and thus contribute to securing food sovereignty.
Since in countries that import animal feed, conventional regional protein sources cannot meet the large demand of industrial animal husbandry, much research is currently being conducted into alternative protein animal feeds. Some of those being currently discussed are microorganisms, algae and insects.
The technology for producing a protein powder out of microorganisms that can be fed to animals was developed in aerospace. Microbes such as bacteria, yeasts and fungi are cultivated and processed in industrial plants. The production is cost-effective and has a favorable ecological balance. An analysis of the potential of microbial protein for feed production showed positive results. It could be concluded that the global area under cultivation, greenhouse gas emissions and nitrogen losses can be greatly reduced.
Microalgae such as spirulina with its protein content of up to 70% and high nutrient density have the advantage that they grow rapidly and can be produced in a closed system with high output. Insects have low demands on their environment and on their food and can also be bred on waste. This means that breeding could also be beneficial for waste recycling. In a study at the Faculty of Agricultural Sciences in Göttingen, both raw materials were subjected to a sample. Pigs and broilers were fed with dried ground larvae of the black soldier fly and spirulina powder. The experiment showed that both feedstuffs brought valuable protein qualities and were well accepted by the animals.
As organic livestock farming aims at a closed operating cycle, clover grass plays an important role as animal feed and soil improver/green manure (as an alternative to chemical fertilizers). Fresh or ensiled, clover grass is used in dairy cattle feeding as protein supplement feed. In Denmark, a technical process has recently been developed to break down proteins from clover grass in order to produce pig feed thereof. It is interesting to note that, according to the authors, the protein composition is more suitable for pigs and poultry than that of soya. The advantages of clover grass even extend beyond its nutritional qualities. Clover grass requires less fertilization than grains and soya, contributes to the building-up of humus and leads to lower nitrogen leaching and need for plant protection. The protein yield is essentially higher than with grains.
Traditional, long forgotten and rarely used feedstuffs such as foliage can also be considered as alternatives.
Alternative protein feeds are advancing into the discourse due to the generally growing awareness of environmental problems by the agricultural industry. There is great interest in Europe to reduce the need for importing soya. The implementation is still failing because of legislation. While algae proteins are permitted in the EU, insect proteins may only be used in aquaculture since 2017.
The approaches presented here for obtaining protein feed from microorganisms, algae and insects are highly industrialized processes. Their breeding will most likely only be carried out on a large scale in Germany, as industrial facilities are required for cultivation and processing. For this reason and because of the many regulations, insect breeding will most likely not be a solution for small-scale agriculture in Germany, unlike in East Asia. At present, it is also not permitted in Europe to feed bred insects with organic waste. Certain risks include unknown insect diseases that can be transmitted to humans, heavy metal contamination and ethical issues. It also remains questionable whether the approved sources of feed for insects would be sufficient in quantity to serve the today's high number of livestock in intensive agriculture.
This is linked to the overarching question of the extent to which the niche of alternative protein feeds puts intensive industrial livestock farming into question. The niche merely replaces a product or a raw material in the intermediate consumption. Since a continuous high consumption of resources can still be assumed, the food system gets thus adapted rather than transformed. In order to reduce the climate-damaging industrial meat production and ethically questionable animal husbandry, it requires a profound change in the consumption patterns.
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