Effect of twin‐screw extrusion on gelatinization characteristics of oat powder

Abstract

The effect of extrusion treatments on oat gelatinization, microstructure, and macroproperties were important during twin‐screw extrusion. In this work, single factor and orthogonal experiments were conducted to evaluate gelatinization degree, expansion ratio, water solubility index, and water absorption index of oat powder before and after extrusion. Results indicated that the optimum gelatinization degree was 96.92% under the conditions of 18% moisture content, 155°C barrel temperature, and 150 rpm screw rotating speed. According to appearance by scanning electron micrograph, the extruded oat changed from the original tightly wrapped texture to spongy and porous form with lower gelatinization temperature (88.00°C) than those without extrusion (91.35°C). Rapid viscosity analysis showed that extruded oat became more stable and easier to gelatinization, which was consistent to the in vitro digestion experiment, suggesting extruded oat could be applied as ready‐to‐eat food in the further application. Practical applications The purpose of this research was aimed to optimize the extrusion and ripening process of oat powder, to explore the effect of curing method on the characteristics of oat powder, and to compare the physical and chemical properties of oat powder before and after extrusion. Eventually, the optimized process of oat powder using twin‐screw extrusion technology improved the structural characteristics of oat powder and enhanced the digestibility of the product.

In Vitro Antioxidant Activity Optimization of Nut Shell (Carya illinoinensis) by Extrusion Using Response Surface Methods

“…reported that samples with higher soluble fiber have greater water and oil absorption [16]. We observed that extrusion produced, in general, higher concentrations of SDF, which were associated with an increased solubility in water [56]. Table 2 shows that the treatments with 150 rpm and 70 • C (4, 6 and 8) present similar results of WAI, OAI, and WSI.…”

Oat-Based Foods: Chemical Constituents, Glycemic Index, and the Effect of Processing

“…Extrusion cooking with high heat, pressure, and shear effects enhances starch gelatinization and structural changes, and this technique is used to make ready-to-eat oat products. Extrusion at 18% moisture content, 155 • C barrel temperature, and 150 rpm screw rotating speed gave the gelatinization degree of 96.92% in oat flour and led to a much easier release of glucose [73]. However, harsh processing conditions such as extrusion can depolymerize β-glucans by breaking glycosidic bonds [74].…”

Effect of extruded corn flour addition on the quality characteristics of fine dried noodles

“…Tang et al (2013) determined composite corn snacks' optimal extrusion process parameters by longitudinal expansion, maximum shear force, and screw speed of the compositions. Wang et al (2019) studied the physical and chemical properties, and gelatinization properties of oat flour, the optimum extrusion parameters of oat flour were determined. Martínez et al (2014) added 10% extruded rice flour to the original flour, increasing the volume of rice flour bread and improving the bread structure.…”