Application of Extrusion-Cooking for Processing of White and Red Bean to Create Specific Functional Properties

Abstract

Extrusion-cooking, as a modern and versatile processing method, may be applied to create the properties of food ingredients and active components, especially beans and legumes. Two varieties of bean (red Toska and white Aura) were extruded with twin-screw extruder under various conditions (water dosing 0.8–2.4 l h−1, screw speed 300–700 rpm). Physical properties (energy consumption, expansion ratio, water absorption and solubility, viscosity, texture, color) and chemical characteristics (protein, fiber, reducing sugars, total phenols, anthocyanins, flavonoids, antioxidant activity and reducing power) were evaluated. Regardless of the bean cultivar, energy consumption significantly increased for about 60% with the extruder screw speed increase, and at the same time, the greater water addition reduced energy consumption by about 30%. The physical properties and texture of extruded bean were significantly connected with processing conditions for both bean varieties. Chemical composition and nutritional characteristics were different for red and white bean, especially phenols and anthocyanins levels were higher in red bean extrudates; significant effects of extrusion variable conditions were found in most characteristics. Nevertheless, the knowledge of the effect of red and white beans extrusion treatment on tested characteristics allows to select processing conditions to achieve ready-to-eat extrudates or functional additives with specific features.