Optimal preparation of food waste to increase its utility for sophorolipid production by Starmerella bombicola

Secondary feedstocks, such as food waste (FW), have been used for yeasts (e.g. Starmerella bombicola) to produce sophorolipids (SLs), which are commercially available biosurfactants. However, the quality of FW varies by location and season and may contains chemicals that inhibit SLs production. Therefore, it is crucial to identify such inhibitors and, if possible, remove them, to ensure efficient utilization. In this study, large scale FW was first analysed to determine the concentration of potential inhibitors. Lactic acid, acetic acid and ethanol were iden-tified and found to be inhibitors of the growth of S. bombicola and its SLs production. Various methods were then evaluated for their ability to remove these inhibitors. Finally, a simple and effective strategy for removing in-hibitors from FW was developed that complied with the 12 principles of green chemistry and could be adopted by industry for high SLs production.

Automated summary

Large scale food waste was analyzed to determine the concentration of potential inhibitors, and lactic acid, acetic acid, and ethanol were identified as inhibitors of the growth of S. bombicola and its SLs production. Various methods were evaluated to remove these inhibitors, and a simple and effective strategy for removing inhibitors from food waste was developed, complying with the 12 principles of green chemistry and suitable for industrial high SLs production.