Circulation-orientated food and feed research

Increasing awareness of the economic and ecological consequences of conventional agriculture, coupled with a steadily growing world population, calls for the development of alternative food, feed and fertilisers.

One of the biggest problems in livestock farming and aquaculture is the use of feedstuffs such as soya and fishmeal, which contribute to the deforestation of rainforests and overfishing of the oceans. For these reasons, insects are currently being developed as an alternative food and feedstuff. However, the economic competitiveness of insects is severely limited by the availability of cheap insect feed and calls for better utilisation of residual materials and side streams from industry and agriculture.

Food production is particularly dependent on the availability of mineral fertilisers. Due to high energy prices and limiting resources such as phosphate, the use of mineral fertilisers is becoming increasingly expensive. It also contributes to the emission of nitrogen oxides and the leaching of nitrate into aquatic ecosystems. Therefore, alternatives in the form of organic fertilisers are increasingly needed for agriculture.

Insect larvae are proving to be a valuable source of protein and have the potential to replace soya and fishmeal in livestock farming and aquaculture. Some insects, such as the black soldier fly (Hermetia illucens) or the mealworm (Tenebrio molitor), can be bred on a small area on a large scale (insect farming). In order to make insect farming more resource-efficient and economical, we are investigating residual materials and low-cost side streams from industry and agriculture as food for insect larvae. Since microorganisms such as bacteria and fungi make a decisive contribution to the digestion of these substances, we are intensively studying the gut microbiome of farmed insects. A better understanding of the microbial communities and their metabolic performance should help to optimise insect farming. In particular, the breeding of insect larvae is to be made more efficient through the use of microorganisms that break down difficult-to-digest plant components of the side streams and thus increase feed turnover. The formation of greenhouse gases during insect breeding will also be evaluated and, if necessary, minimised by adapting the breeding conditions. In addition to the gut microbiome, we are also investigating the microbial communities in the frass of various breeding insects such as the black soldier fly and the mealworm. The frass is a by-product of insect farming (consisting of faeces, feed residues and insect exuviae), which can be used as an alternative to mineral fertiliser. Depending on the feed used, the chemical and microbial composition of the manure can vary and thus also influence the fertiliser properties. In cooperation with small and medium-sized companies from the insect farming sector, we are working on the comprehensive characterisation of frass in order to develop needs-based fertilisers for agricultural applications. In the long term, our research should contribute to a climate-friendly, circular bioeconomy under low- or zero-waste conditions.