Novel nutrient dense quinoa fractions: physical, functional, thermal and rheological characterisation for potential industry application

Abstract

Quinoa is known for its unique nutritional characteristics and contains good quality protein and fat along with appreciable amount of starch, dietary fibre and micronutrients. The fractionation facilitated the separation of the botanical components of the grain which were found to be rich in specific nutrients. The protein- and fat-rich fraction (PFRF) projected 2.15 times protein and 2.74 times fat, while fibre-rich fraction (FRF) showed 2.35 times fibre content as compared to quinoa whole grain. Starch-rich fraction (SRF) with 82.41% starch was lower in protein content. FRF showed higher water holding capacity compared with other quinoa samples where bulk density was reported highest in PFRF fraction (670 kg per m3). These fractions showed variation in their gelatinisation enthalpy for the thermal properties. Foaming and emulsion properties were significantly impacted by the composition of the fractions and varied at different pH. The apparent viscosity was recorded highest for FRF, where SRF was lowest. At varied temperatures tested, the exhibited behaviour of all samples was found to be non-Newtonian in nature. Present study concludes that quinoa physical fractionation produced novel nutrient dense fractions with unique techno-functional features and has potential to be explored for food product development as independent functional ingredient.