Long-lasting staple products
Though food-extrusion is often associated with "fun" products like snacks and breakfast-cereals in a wide variety of shapes, sizes, colours and flavours targeted to children, the technique is also employed for some staple foods. One such product category is that of "flat-bread" or "crisp-bread".
"Flat-" or "crisp-bread" is essentially an extruded strip that is cut into specified length and dried to a low enough moisture level to enable a long shelf life under ambient conditions.
The advantages of the extruded flat-bread are -
- Option of using various blends of different cereals to achieve desired taste, texture and nutritional value
- Long shelf life without special storage environment
- Easy transportation and use for different occasions
- Diverse uses; can be eaten with various toppings, or asa sandwich with a filling in between two slices.
Pre-extrusion: two or more cereal raw materials are usually blended and moisturised with water to a pre-determined level prior to extrusion. The moisturised raw material is fluid when it is transferred into the extruder using screw dosing units.
Extrusion: the raw materials are extruded and formed into an expanded strip using a special die system. The texture of the product can be controlled in the Schaaf extruder to correspond to the market requirement.
Drying and Cutting: since the extrudate is not dry and hence not crunchy, it is passed continuously through an infrared belt oven to reduce the moisture levels. After the moisture in the strip has been reduced and the strip has become crunchy, it is cut to the specified length using various cutting options.
Stacking and Packaging: the cut product pieces are stacked using a continuous stacking system and then packed online or by manual transfer using a flow wrapping packaging system.