Abstract:

Glutinous rice was extruded by a single screw extruder for gelatinization. The degree of gelatinization (DG) was
investigated with respect to three extrusion parameters including the moisture content and particle size of the raw material
as well as extrusion temperature, and maximized by optimizing these three parameters using response surface methodology.
The glutinous rice flour with a particle size of 100 mesh (0.147 mm) and a 31% moisture content exhibited the highest
value of DG after extrusion at 155 ℃. High performance liquid chromatography (HPLC) analysis showed that the glutinous
rice extruded under optimal conditions contained 17.21 mg/g xylose, 99.99 mg/g glucose, 48.64 mg/g sucrose, 42.35 mg/g
maltose and 18.96 mg/g maltotriose. Therefore, single screw extruder can be a promising alternative to traditional cooking
for glutinous rice gelatinization.

Key words: glutinous rice, extrusion, gelatinization