Numerical optimization of process parameters of water chestnut flour incorporated corn‐based extrudates: Characterizing physicochemical, nutraceutical, and storage stability of the developed product

Abstract

The present research was undertaken to optimize process conditions for development of water chestnut incorporated corn-based extrudates. The independent extrusion variables—feed composition, feed moisture, screw speed and barrel temperature were studied to determine their influence on dependent variables-specific mechanical energy, expansion index, bulk density, water solubility index, water absorption index, hardness, and color. All system and product responses were significantly (p < .05) influenced by independent variables. The regression models fitted to experimental design showed high coefficient of determination (R2 ≥ 0.99). The optimum conditions for development of extrudates obtained by numerical optimization were corn flour : water chestnut flour (60:40), feed moisture (14%), barrel temperature (170°C), and screw speed (300 rpm). Moisture, protein, and fat contents of extrudates developed using optimum conditions were significantly (p < .05) lower than corn and water chestnut. Storage studies revealed safe storage of extrudates packed in aluminum laminates up to 120 days under ambient conditions without compromising much of its qualities. Practical applications Water chestnut possesses excellent therapeutic potential owing to the presence of bioactive compounds including glycosides, phytosterols, flavonoids, and tannins, which may help in alleviating various diseases. Besides, water chestnut has low glycemic index; thus, the developed products prepared from it may be suitable for diabetics. Extruded products have better consumer acceptability in terms of shelf life and organoleptic characteristics. Therefore, the extruded products developed from nutritionally rich water chestnut would be a better alternative to already available extruded snacks in food industry. It can open up a new horizon in the field of extrusion products.