Towards a next generation of meat alternatives

Meat is an important component in many pet food recipes. The big difference between pet foods and food products for human consumption is the fact that (most) pets completely depend on pet food products for their nutrition. This implies that nutritional value becomes even more critical for those products, compared to products for human consumption (especially in Western diets). Currently, extrusion is the main route to make pet food, which will therefore be the initial structuring technology of interest in this research line. The purpose of shearing devices will be to test novel components and diets on small scale. Plant materials, such as legumes, contain components that contribute to a healthy diet for pets, but also components that are less desired, or should even be removed before the plant material can be used in the application. This project will therefore start with making an inventory of potential plant protein sources. Key elements in the comparison will be protein quality and nutritional profile (i.e. amino acid profile, the presence of anti-nutritional factors (ANF) and expected digestibility). Besides, simple heating will be used to get an impression of properties, such as water binding and gelation capacity, that are relevant for final product characteristics such as palatability. Based on this inventory, a selection of two or three plant proteins will be selected that will be tested in more depth. The behavior of the components will be investigated using extrusion-like conditions, for example by using shearing devices. Analytical methods that are currently available and developed in research line 4 will be used to characterize the chemical changes in the material upon processing (effects on ANF, amino acid profile, Maillard). The digestion will be studied as well. After that, complete diets will be evaluated and selected for larger extrusion trials. From those products, an extensive characterization will be made using available techniques (i.e. texture analysis). If required, a microstructural analysis can be made using techniques like XRT, or microscopy techniques such as CSLM. The product properties will be compared with given standards and in case of too much deviation, suggestions for improvements will be made. Products can be made softer by including protein sources that absorb little water (i.e. lupine) or strengthened by strongly water binding protein sources, such as soy. If required, proteins can be altered through thermal preprocessing and/or enzymatic modification. In the final stage of this research line, a connection will be made with research lines E1 and E2 of the Plant Meat Matters project, in which novel fractions from plant raw materials are developed. It will be tested whether integration of fractionation and structuring (process symbiosis) can also lead to additional advantages in pet food application with respect to nutritional profile, product properties and sustainability aspects.