Rheological, techno-functional, and physicochemical characterization of Prosopis cineraria (Sangri) seed gum: A potential food and pharmaceutical excipient

Prosopis cineraria is an underutilized legume native to the western part of India and their pods are known as Sangri. The present investigation is intended to optimize the alkaline co-extraction of gum and protein from Sangri at different process conditions using response surface methodology. The optimized conditions thus obtained were pH 10 for 90 min at 70 degrees C which yielded 232.7 g kg(-1) of protein and 9.34% of Sangri gum upon isoelectric precipitation and isopropanol flocculation. The yield was further increased to 331.33 g kg(-1) of protein and 12.6% of Sangri gum by the sequential triple co-extraction. The Sangri gum was further characterized for a zeta potential of -29.7 mV, a particle size of 12.15 nm, and a molecular weight (MW) of 4.66 x 10(4) Da with an amorphous nature. It showed higher emulsification and foaming capacity as compared to guar gum and locust bean gum at lower concentrations with low levels of anti-nutritional factors. Novelty impact statement This is the first report of co-extraction of Sangri seed gum (SG) and soluble protein from Prosopis cineraria seeds. SG showed good oil holding capacity, emulsification index, rheological properties, and is thermally stable. SG can be used as a food or pharmaceutical micro-encapsulating agent, binder, and matrix material intended for controlled drug, flavor, or nutrient release especially in the acidic pH.