Use of organic acids to improve fractionation of the black soldier fly larvae juice into lipid- and protein-enriched fractions

This study focusses on the fractionation of proteins and lipids from insect biomass, more specifically from black soldier fly larvae. Insects are rich in proteins and lipids and offer potential as a protein source for food and feed. Fractionation processes often focus on extracting only one compound (lipid or protein), neglecting the impact of the extraction method on other compounds. The current study aimed at the development of a robust fractionation process for wet insect biomass, targeting enriched protein fractions with higher valuable techno-functional properties as well as enriched lipid fractions. The use of different organic acids was evaluated and compared with an inorganic acid (HCl). A beneficial effect of organic acids on the lipid extraction yield (shift from 35 to 45%) was observed, that did not negatively influence the protein extraction efficiency. One organic acid, in particular, lactic acid, increased the lipid purity from 75 to 85%. Protein fractions with a purity of 60% proteins were achieved and were shown to preserve partial solubility. Use of some organic acids at low pH (pH 2) resulted in (1) a higher lipid purity in the lipid-enriched fraction and (2) had similar results in protein fractionation as the inorganic acid. Reproducibility of the fractionation process was proven.