In the study \"Physico-chemical properties of extruded aquafeed pellets containing black soldier fly (Hermetia illucens) larvae and adult cricket (Acheta domesticus) meals,\" researchers substituted FWSM protein in a 26 g/100 g protein fish feed formulation at 0, 25, 50 and 75%, and adjusted moisture content of the formulated blends to 10, 20 or 30 g/100 g prior to extrusion.

Floatability, expansion rate, bulk density, durability index, water absorption index, water solubility index, and water stability of extruded pellets were determined. Sinking velocity and the total suspended and dissolved solids in water were determined for the optimal pellets.

Results found that pellet floatability and expansion ratio were not influenced by the type of insect meal, but the moisture content of the feed at extrusion made a difference. Pellets with high floatability >90% and high expansion ratio ~60% were produced from all feed blends at 30 g/100 g moisture content. 

Overall, the study found it was possible to process good quality extruded pellets with 75% BSFM or 75% ACM at 30 g/100 g feed moisture. 

This article includes excerpts from the study abstract, published in the Journal of Insects as Food and Feed