Droplet breakup and coalescence in a twin-screw extrusion processing of starch based matrix

► Droplet breakup and coalescence in an extruder are separately investigated. ► Increasing screw speed improves breakup but also leads to higher coalescence. ► Increasing feed rate increases blend viscosity, and thereby reduces coalescence. ► Higher oil content results in increased coalescence. ► Screw configuration can be altered to improve breakup and to reduce coalescence.