The effects of some operating conditions on oil loss and physical properties of products obtained by doughs containing almond flour extruded in a co-rotating twin-screw extruder were investigated. The results showed that the lowest loss of oil was obtained at low percentages of dough moisture and high values of screw speeds. The extrusion parameters that greatly influenced the structural characteristics of extruded products were dough moisture and screw speed. In particular, the best results were obtained by extruding at 36% dough moisture and 200 rpm screw speed. The operating conditions suitable to obtain both a low oil loss and a good product structure were low percentages of dough moisture and high values of screw speed and extrusion temperature. (c) 2004 Elsevier Ltd. All rights reserved.