Comprehensive nutritional and biofunctional assessment of insect-enriched coconut (Cocos nucifera L.) milk kefir: from micronutrients to enzyme inhibition

This study investigates the nutritional and biofunctional potential of kefir enriched with methanol and aqueous extracts of edible insects (Macrotermes nigeriensis and Ruspolia differens, green and brown forms). In this context, the comparative evaluation of two different edible insects and their two different extracts in coconut milk-based kefirs for the first time has provided an innovative perspective on the use of alternative functional compounds in plant-based kefir production. Insect extracts were incorporated into traditionally produced kefir, and the resulting formulations were analyzed for amino acid and phenolic compound profiles using LC-MS/MS. In addition to physicochemical analyses, antidiabetic and anticholinesterase activities were also evaluated. The results showed that kefir enriched with methanol extract of green R. differens had the highest levels of bioactive and nutritionally relevant amino acids, including threonine, alanine, and ethanolamine. Additionally, the water extract of brown R. differens yielded the highest concentrations of quinic acid, fumaric acid, and 4-hydroxybenzoic acid. Significant differences (P < 0.01) were detected in terms of physicochemical properties and the positive contributions of the extract addition were recorded. On the other hand, only α-amylase inhibitor activity was determined in the samples, and it was found that the addition of edible insect extract led to a decrease in inhibition compared to the control samples. The findings demonstrate that insect-based kefir formulations significantly enhance nutritional quality and functional properties, offering promising applications in the development of sustainable and health-promoting functional foods.