Influence of pretreated food waste on the nutritional value, functional properties and lipid quality of Black soldier fly (Hermetia illucens) larval products

This study aims to assess the effect of pretreated food wastes collected from restaurants on the nutritional and functional properties of powders and the quality of lipids from black soldier fly (Hermetia illucens) larval products. The food wastes were pretreated in different manners, such as no treated wastes or control (T0); crushed waste (T1); stewed waste (T2) and fermented waste (T3). Later, they were used to feed 7-days-old black soldier fly larvae (BSFL) during 15 days of rearing. The nutritional and techno-functional properties, lipid quality and fatty acid profile of the larvae’s fats were then evaluated. Results showed that for the nutritional value, the pretreatment of food waste significantly (p<0.05) increased the protein content and ash content of BSFL powder where for the protein content, values varied from 32.02 to 39.11% for T1 and T0, respectively; while for the ash content, they varied from 7.92 (T0) to 11.04% (T3). Concerning the fatty acid composition of BSFL, the treatment of food waste tends to increase the number of fatty acids compared to the untreated sample (T0). Also, the total fatty acid composition revealed a higher proportion of saturated fatty acid (62.07–74.64%), followed by monosaturated fatty acid (19.20-25.02%) and polyunsaturated fatty acid (6.16–14.65%). Thus, bioconversion of treated food waste using BSFL can be useful for the production or formulation of added-value food products. Black soldier fly larvae (BSFL) can be useful for the bioconversion of local food wastes. BSFL flours reared with food wastes showed good nutritional properties. Defatted flours of BSFL can be used for the formulation of food products. Lipids extracted from BSFL are very rich in saturated fatty acid, and can be exploited for industrial purposes.