<i>Effect of extrusion conditions on pasta quality from wheat flour and cassava starch</i>

Abstract

Abstract. The inclusion of local cassava cultivars as a composite flour in the production of major staple foods like pastry and pasta is necessary for their value addition. This study aimed to evaluate the effect of extrusion conditions on the quality characteristics of extruded pasta made from a composite wheat flour and cassava starch. In the response surface design applied, three extrusion conditions (screw speed, barrel temperature, and composite flours) were investigated to determine their effects on pasta quality from wheat flour and cassava starch. Cassava starch was added in different proportions (0 – 20%) to durum wheat (0 – 100%), salt (1%) and monoglycerides (0.50%). The formulation was extruded at 25% uniform moisture content, 150 – 250 rpm screw speed, and 60 - 70℃ die temperature using a co-rotating twin-screw extruder with a feed rate of 3 kg / h. The results showed that the screw speed, barrel temperature, and composite flours influenced pasta quality. The optimum screw speed, barrel temperature, and composite flour are 200 rpm, 65℃, and 90% durum wheat flour plus 10% cassava starch were obtained, respectively. The optimum extrudate moisture content, water absorption, cooking loss, specific mechanical energy, degree of gelatinization, minimum viscosity, maximum viscosity, hardness, fracturability, adhesiveness, springiness, cohesiveness, gumminess, chewiness and resilience of 22.83%, 130.69%, 10.30%, 1.50 KJ/kg, 52.09%, 1.25 Pa.s, 3.18 Pa.s, 39.05 g. force, 98.01 g.force, 138.12 g.s, 1.88, 0.80, 55.0, 87.5 and 0.16 were obtained respectively. The study showed the potential of using cassava starch in composite flour to produce quality extruded pasta.