Silkworm pupae (Bombyx mori) and locusts as alternative protein sources for high-energy biscuits

This study explored the possibility of replacing skimmed milk – a core ingredient of High-energy biscuit (HEB), with edible-insects as inexpensive and sustainable alternative sources. HEB was formulated to meet the USAID 2016 (STD) nutritional standards and powdered locust and mulberry silkworm pupae (LP and SWP) at 15% inclusion, were used as alternative protein sources. Preliminary nutrients composition of the insect powders were examined. Physicochemical, sensory and microbial qualities of insect-enriched biscuits (LPB and SWPB) were evaluated and compared with that of skimmed milk (SMB) and STD. Spread ratios of the biscuits were between 7.8 and 11.6 – a technically acceptable range for biscuits. SWP possessed impressive amounts of protein (60.7 g/100 g), fat (23.5 g/100 g) and energy contents (498.93 kcal/100 g), while LP had slightly more fibre (1.4 g/100 g), ash (2.1 g/100 g) and carbohydrate (31.5 g/100 g). LPB and SWPB had relatively similar proximate compositions as SMB with slight variations, and all the HEBs were above USAID minimum standard. SWPB was marginally below requirements for Ca and Mg minerals, but both (SWPB and LPB) had more than twice the recommended pro-vitamin A (918.44 and 957.65 µg/100 g) and vitamin C contents (102.17 and 98.51 mg/100 g). All the samples received reasonably good sensorial rankings; but SMB’s aroma was preferred. Similarly, microbial quality assessment of the products reflected remarkable hygienic sample preparation. These results demonstrated that HEB of significant nutritional, sensorial and microbial qualities could be developed using edible-insects as alternative protein sources.