Material for pellets was extruded in a single-screw extruder
(Brabender DN 20, Germany). The following extrusion parameters
were kept constant: die size (0.5 mm 80 mm), speed of dough
supplier (38 rpm), screw speed (120 rpm), screw loading (2.8 A)
and barrel temperature distribution (60 C/70 C/80 C). Strands
that had previously been subjected to extrusion but were not
expanded were cut into pellets of ca. 27 27 mm and dried at
room temperature for 12 h to ca. 12–13% moisture content and
sealed in polyethylene bags to equilibrate moisture until frying.