Larval biomass production from the co-digestion of mushroom root waste and soybean curd residues by black soldier fly larvae (Hermetia illucens L.)

Abstract

Black soldier fly larvae (BSFL) are progressively being used as a sustainable waste management solution. They are high in protein and other essential nutrients, making them an ideal food source for livestock, poultry, and fish. Pure mushroom root waste (MRW) has been shown in the past to have a poor conversion efficiency, taking much more time than regular artificial diet in prior laboratory studies. Therefore, the nutrient rich soybean curd residues (SCR) was mixed with MRW, the combination of SCR and MRW increased the diversity of the gut microbiota, which was favorable for the development and growth of the larvae. As compared to all of the other feed combination groups, the longest developing period of BSFL in (M1) pure MRW was 31.1 days. When compared to the M1 and M7 groups, the mixture groups achieved the highest reductions in dry mass (49.7%), bioconversion rate (5.9%), protein content (46.0%) and lipid content (25.2%). Based on the different performance parameters of different mixtures of MRW and SCR, Lipid and protein content and FCR in BSFL were the essential parameters to evaluate the conversion efficiency of BSFL. SEM pictures and FT-IR spectra indicated that the group M4 MRW structures altered to hollow and fiber excision, which improved the co-conversion mixture. BSFL (M4) can co-convert fiber rich MRW with SCR.