This project has produced fishmeal analogs from black soldier fly (Hermetia illucens) larvae (BSFL) by rearing them on seafood processing byproducts that are currently being discarded at the expense of the seafood processor. A comprehensive set of evaluations have been conducted in which BSFL were reared in two pilot-scale trials, two benchtop trials and one industrial-scale trial on substrates consisting of different percentages of Gainesville commercial fly diet and three different seafood processing byproducts. The processing byproducts consisted primarily of head and skeleton (racks) of yellowfin tuna (Thunnus albacares), Atlantic salmon (Salmo salar) and red drum (Sciaenops ocellatus) after fillet removal. The various BSFL rearing trials compared substrates consisting of either a 50/50 or a 75/25 ratio of seafood processing byproducts to Gainesville diet as well as the 100% Gainesville substrate. The various substrates resulted in different compositions of the BSFL with those reared on tuna byproduct having the highest crude protein and lowest lipid relative to the other substrates (Table 1). Significant changes also were observed for both saturated and unsaturated fatty acids in the BSFL (Table 2).
The BSFL reared on the various substrates were evaluated in terms of nutrient and energy digestibility with sub-adult red drum. Apparent digestibility coefficients (ACDs) for energy, protein, lipid and organic matter were considerably higher for the BSFL reared on processing byproducts compared to the Gainesville substrate (Table 3).
Results from an ongoing comparative feeding trial with red drum also will be presented. The nutritional value of BSFL is favorably altered by seafood processing byproducts and allows the recovery of valuable marine nutrients.