Characterization of frass Derived from black soldier fly treatment of decanter cake

Abstract Black soldier fly frass (BSFF), a byproduct of black soldier fly larvae (BSFL), shows promise as a nutrient-rich organic fertilizer. In this study, comprehensive characterization of BSFF obtained from the treatment of decanter cake by the BSFL was conducted employing CHNS analysis, microwave digestion, atomic absorption spectroscopy (AAS), spectrophotometry, and moisture analysis. The objective of this work is to compare experimental findings on frass characterization to literature values obtained from various studies. The moisture content was determined to be 34.10%, while the elemental composition showed percentages of Carbon (C) at 38.28%, Nitrogen (N) at 2.47%, Phosphorus (P) at 0.0024%, and Potassium (K) at 0.0023%. It can be observed that the NPK content of the frass derived from decanter cake is significantly lower especially phosphorus and potassium content. Hence, this work can serve as a baseline for nutrition enhancement via co-composting with potential additives which able help to improve the nutrient content.