High-moisture extrusion with insect and soy protein concentrates: cutting properties of meat analogues under insect content and barrel temperature variations

Insect biomass production is recognised as one of the potential solutions for the problem of a lack of traditional protein sources (most feed protein sources are imported in Europe). It is perceived to be utilised as a more suitable source of proteins for food and feed in Western countries within the next decades. High-moisture extrusion of protein concentrate and water mixtures results in the development of fibrous intermediates, suitable for the development of meat analogues. Hardness and protein composition of such intermediates were comparable to meat. Inclusion of 15-40% of insect protein concentrates (both Alphitobius diaperinus and Tenebrio molitor) could imitate the meat texture and resulted in a similar hardness compared to a standard sample composed of 100% soy protein concentrate (dry matter basis). Extruder barrel temperature and soy-insect ratio were found to affect the physical properties of the extrudates: an increase in temperature (alternatively decrease in water input) improved the hardness of the intermediates from 6.5-8 N (barrel temperature 160 degrees C) to 8-11 N (barrel temperature 170 degrees C). An optimal meat-like texture with the highest inclusion of insect biomass (40% dry matter basis) was achieved when using a maximal temperature of barrel extruder of 170 degrees C. The results demonstrated the potential of insect protein incorporation in a mixed ('Invisible') form to generate high-protein texturized intermediates, presenting a viable alternative to the fresh meat products.