Biological evaluation of protein quality of raw and processed seeds of an underutilized legume sickle pod (Cassia obtusifolia L.)

The nutritional and anti-nutritional profiles as well as biological value and protein quality of raw and differentially processed seed materials of an under-utilized sickle pod seeds (SPS)(Cassia obtusifolia L.) were analyzed. The raw seeds were found to contain higher levels of crude proteins (27.30%), crude lipids (6.06%), crude fibers (9.70%) and ash content (5.60%). Even though, certain nutritionally undesirable anti-nutritional substances were present in the raw SPS, the autoclaving treatment is more effective in reducing the maximum levels of total free phenolics (81%), tannins (85.7%), L-Dopa (79%), phytic acid (77%), oligosaccharides like raffinose (77%), stachyose (73%) and verbascose (75%), haemagglutinating activity (69%), trypsin inhibitor activity (72%) and amylase inhibitor activity (78%) without affecting the nutritional quality. The experimental animals fed with autoclaved SPS samples exhibited better growth performance such as feed intake (FI) (192 g 28 days⁻¹), body weight gain (BWG) (51.3 g 28 days⁻¹), feed conversion ratio (FCR) (0.26) and protein efficiency ratio (PER) (2.67). Further, the protein quality such as true digestibility (TD) (78.5%), biological value (BV) (73.6%), net protein utilization (NPU) (54.7%) and utilizable proteins (UP) (16.45%) of the animals fed with diet containing autoclaved SPS samples were also found to be higher than the raw and other processed SPS included diets.