title: The Effects of CO2Injection and Barrel Temperatures on the Physiochemical and Antioxidant Properties of Extruded Cereals.
abstract: The effects of CO2injection and barrel temperatures on the physiochemical and antioxidant properties of extruded cereals (sorghum, barley, oats, and millet) were studied. Extrusion was carried out using a twin-screw extruder at different barrel temperatures (80, 110, and 140°C), CO2injection (0 and 500 mL/min), screw speed of 200 rpm, and moisture content of 25%. Extrusion significantly increased the total flavonoid content (TFC) of extruded oats, and β-glucan and protein digestibility (PD) of extruded barley and oats. In contrast, there were significant reductions in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, PD of extruded sorghum and millet, as well as resistant starch (RS) of extruded sorghum and barley, and total phenolic content (TPC) of all extrudates, except extruded millet. At a barrel temperature of 140°C, TPC in extruded barley was significantly increased, and there was also an increase in DPPH and PD in extruded millet with or without CO2injection. In contrast, at a barrel temperature of 140°C, the TPC of extruded sorghum decreased, TFC of extruded oats decreased, and at a barrel temperature of 110°C, PD of extruded sorghum without CO2decreased. Some physical properties [expansion ratio (ER), specific length, piece density, color, and water absorption index] of the extrudates were significantly affected by the increase in barrel temperature. The CO2injection significantly affected some physical properties (ER, specific length, piece density, water solubility index, and water absorption index), TPC, DPPH, β-glucan, and PD. In conclusion, extruded barley and millet had higher potential for making value added cereal-based foods than the other cereals.
authors.affiliation: Department of Food Science and Technology, Kongju National University, Chungnam 32588, Korea.
authors.forename: Thazin
authors.initials: T
authors.lastname: Thin
authors.affiliation: Department of Plant Pathology, Yezin Agricultural University, Pyinmana, Myanmar.
authors.forename: Lin
authors.initials: L
authors.lastname: Myat
authors.affiliation: Department of Food Science and Technology, Kongju National University, Chungnam 32588, Korea.
authors.forename: Gi-Hyung
authors.initials: GH
authors.lastname: Ryu
keywords: CO2 injection; antioxidant properties; cereals; extrusion; physiochemical properties