EFFECTS OF PREGRINDING AND EXTRUSION ON QUALITY OF CORN TORTILLA FLOUR

The effects of stone and pin milling (with and without subsequent extr usion) on quality parameters of tortilla flour were studied and quanti fied with the aid of a laboratory extruder. The viscoamylograms of sel ected flour samples were also determined. Results revealed that tortil la flour of good quality could be obtained by stone milling (with or w ithout subsequent extrusion) but not pin milling, even with subsequent extrusion. Although the stone milled samples reflected adequate flow quality parameters, their viscoamylograms were different in many respe cts from that of a commercial tortilla flour sample which resembled th e viscoamylogram of raw flour.