Avaliação da qualidade protéica de dois suplementos alimentares em ratos Wistar

Abstract

The aim of this research was to evaluate the protein quality of two dietary supplements - a protein formulate (a product in test) and gelatin. Six groups of six weanling male Wistar rats were fed with the different diets for fourteen days: control (C 10 - casein), protein formulate (FP 10 ) and gelatin (G 10 ) at 10 % protein level; mixtures with casein and protein formulate (C 7 FP 3 ) or gelatin (C 7 G 3 ) (7:3 in protein base, respectively); and non-protein diet. The protein formulate diets showed good quality protein, according to Net Protein Ratio (NPR) and Net Protein Utilization (NPU) indexes, without significant differences between C 7 FP 3 and C 10 (NPR= 4.00 and 4.11, and NPU= 65% and 67%, respectively). The animals fed with gelatin (G 10 ) and with non-protein diet lost body weight and their liver weights were similar and lower than the liver weights of the other groups of rats (p<0.05). The protein value of the mixture casein-gelatin (C 7 G 3 ) was lower than the value of casein (relative NPR= 77 %, p<0.05). Protein formulate is a source of good quality protein and its use could be indicated in special situations as a dietary supplement. Gelatin, on its turn, could not be considered a nutritional complement or supplement because it does not supply the organism protein requirements and could impair the biological availability of good quality proteins.