Physicochemical, microbiological and nutritional quality of fermented cricket (Acheta domesticus) paste

Abstract

House crickets (Acheta domesticus) were processed into a seasoning paste, the so-called fermented cricket paste (FCP), by mimicking the production process of Thai fermented shrimp paste (Kapi). Whole house crickets were ground with solar salt (crickets to salt ratio = 10:1 w/w), sun-dried to ∼50% moisture content and fermented at 30 °C for 4 weeks using Kapi (5% w/w) as a starter culture. Results showed that salting and drying steps might contribute greatly to eradicating undesirable microorganisms by lowering the Aw of cricket from 0.9 to 0.7. The changes in physicochemical properties during FCP preparation could be attributed to the activity of lactic acid bacteria, which were predominant microorganisms in the FCP (5.66 log CFU/g DW). Overall, the FCP had similar characteristics to commercial Kapi products and should be well-preserved without refrigeration. Despite the lower overall nutritive value, the FCP possessed an improved amino acid profile and protein digestibility compared with the raw material (93.80% vs 81.91%), indicating that the FCP preparation process dealing with fermentation could enhance the protein quality of house crickets. The FCP could be used as a protein-rich seasoning and an alternative for fermented shrimp paste, thus helping to promote the consumption of insect-based foods.