Various methods for preparing snacks by extrusion-cooking are known.
Accordingly, for example, U.S. Pat. No. 4,246,293 (J. M. Larson) describes a method of preparing a snack based on protein-enriched potato, in which potatoes which have been cut into slices are blanched, they are pre- dried, a protein-rich additive is mixed into them and the mixture is reduced to a puree which is extrusion-cooked to give a sticky strip which is cut into cylinders 1.27 cm in diameter, and these cylinders are passed through a deep-fryer. A product thus obtained has a relatively high fat content.
U.S. Pat. No. 5,262,190 (Cunningham et al.) describes a method of preparing a meat-based snack, in which a mixture comprising at least 5% meat, at least 50% flour and less than 4% fat is prepared, the mixture is extrusion-cooked and an expanded sausage is obtained, which can be dried and flavored, in particular with a taco or cheese flavoring, for example. A product thus obtained has a relatively low fat content, but its texture differs appreciably from that of traditional tortillas, crisps or crackers obtained by passing a piece of pastry based on wheat, potato or corn flour, for example, through a deep-fryer.