Table 4. Effect of extrusion parameters on the browning index.

Raw material	Barrel temperature	Moisture	Screw speed	Reference
Sorghum and barley blend	+	-	+	( Koa et al., 2017)
Barley varieties	+	-		( Sharma et al., 2012)
Soybean and sweet potato			+	( Iwe et al., 2004)
Sweet potato flour	+	-		( Waramboi et al., 2013)