Equipment, processing parameters and ingredients all are crucial factors determining the properties of texture vegetable proteins. One twin-screw extruder manufacturer, Clextral, notes that specific processing profiles can be used to create textured proteins with a wide range of physical attributes.

Product characteristics that can be varied include fibration (sheets or longitudinal); surface appearance (smooth, rough, shiny, matte, even or marbled); color (lighter as in chicken, pork or tuna; colored or dark as in beef-colored); texture (consistent, firm, soft, elastic) and taste.

The extrusion process has an added food safety benefit in that the heat and pressure sterilizes the ingredients, which is particularly important when processing animal by-products. Clextral Inc., Laurent Garcia, 813-854-4434, ext. 107,