Black Cricket ( <i>Gryllus assimilis</i> ) Flour, Alone or Combined With Soybean Flour, Enhances Protein Digestibility, Metabolic Health, and Gut Integrity in Wistar Rats

Black cricket (Gryllus assimilis) is notable for its high protein content and dietary fiber in the form of chitin, which may benefit gut health. However, in vivo studies assessing its protein quality and physiological effects remain scarce. This study aimed to evaluate the protein quality of black cricket flour (CF), either alone or in combination with soybean flour (CFSF), and its effects on metabolic markers and intestinal health in Wistar rats. Forty male rats were distributed into five groups (n = 8): control (AIN-93G), cricket flour (CF), cricket flour + soybean flour (CFSF), soybean flour (SF), and protein-free diet (PF). Protein quality was assessed through feed efficiency ratio (FER), protein efficiency ratio (PER), net protein ratio (NPR), and true digestibility (TD). Biochemical markers and intestinal health indices were also analyzed. All test groups presented PER > 2.0 and TD > 90%, confirming good protein quality and digestibility. CF reduced glucose and total cholesterol levels, whereas CFSF lowered total cholesterol and triglycerides. All test groups reduced LDL, while SF increased urea and creatinine. Regarding intestinal health, CFSF increased fecal moisture without altering pH. Acetic and butyric acid production did not differ among groups (p > 0.05), while propionic acid was reduced in all test groups compared to the control (p < 0.05). Black cricket flour, especially in association with soybean flour, is a promising protein source, with beneficial effects on intestinal health.