EFFECT OF EXTRUSION PROCESS VARIABLES ON THE PRODUCT TEXTURE OF BLENDS OF MINCED FISH AND WHEAT-FLOUR

The effect of the extrusion process variables, such as length/diameter (L/D) ratio of the extruder, feed ratio (ratio of the solids of fish and wheat flour), temperature of extrusion, and screw speed, on the pr oduct texture, obtained by extrusion of blends of partially dried low- cost minced fish and wheat flour, were studied. A single-screw variabl e-length cooking extruder, with a barrel bore of 25 mm, was developed for this purpose. The heat stability of the cooked extruded rods in bo iling water was assessed. The texture parameters (hardness, springines s and cohesiveness) of the cooked rods were determined and were compar ed with those of cooked fish, with the objective of developing a fish analogue by means of extrusion cooking. Among the process variables, a n increase in L/D ratio or feed ratio increased these texture paramete rs; the effects of temperature of extrusion and screw speed on the tex ture parameters were complex in nature.