Protein quality of flour from different species of edible winged termites and the effect of termite flour-supplemented diets on hematological plus biochemical indices of rats

Abstract

Edible insects are lately a research niche due to their promising nutrition and sustainability benefits. Protein profiling of a food at laboratory scale or invitro tests require validation through invivo assays to guide regulatory food standards and human nutrition intervention programmes, especially where such a protein food contains antinutritional compounds at laboratory analysis. The present study thus aimed at comparing protein quality in flour from four species of edible winged termites through a rat model, and investigating the effects of termite flour-supplemented diets on hematological plus biochemical indices. A total of 36 weanling male albino rats were distributed across 4 termite-supplemented diets (different termite species in each diet), a casein (control) diet, and a basal diet, with 6 rats in each group, and were fed on these diets for 28 days. Rats fed on Macrotermes bellicosus, Pseudocanthotermes spriniger, and Odontotermes lateritius diets produced the significantly highest weight gain (18.92 to 19.21 g), biological value (87.22 to 88.09%), relative kidney weight (0.91 to 0.97 g/100 g) and liver weight (5.50 to 5.84 g/100 g). Exceptionally, rats fed on the M. bellicosus diet produced the significantly highest protein efficiency ratio (1.97), net protein ratio (3.72), and hemoglobin level (14.31 g/dL). The true digestibility, total plasma protein, and packed cell volume for rats fed on M. bellicosus diet and casein diet were comparable. Similarly, rats fed on the casein diet produced statistically similar white blood cell count with those fed on the O. lateritius diet, yet their (casein-fed rats) biological value and aspartate transaminase activity were comparable to that of rats fed on Macrotermes subhyalinus diet. Present findings revealed that M. bellicosus and P. spriniger-supplemented diets produce high protein quality whereas the casein diet generally outcompetes the M. subhyalinus-supplemented diet. Results of the present study could find applications in development of high quality protein-rich foods from edible winged termites, for use during nutrition-intervention programmes/campaigns.