The Cooking-Extrusion Process

The process itself is relatively simple. Cereal, typically maize or wheat, is fed into the circular barrel of the extruder, a screw pushes the product towards the outlet point, compressing the material as it does so to an extremely high pressure (around 2,000psi). The compression heats the cereal to around 180 degrees C and changing it into the form of a syrup. It is then extruded through a die at the outlet of the machine, the natural moisture flashes off and the product expands into a cellular structure, having a volume about 30 times greater than the original raw material. The product might then be dried to remove the remaining moisture before having oil and flavour added to its outside surface. For snacks the end product is about 30 times greater in volume than the raw material that was put in.

If the snack is cooled just before extrusion, there is no steam flash-off with the result that, after drying, is small pieces of easily stored and transported product which simply require frying before packaging for sale. This means that a basic product can be produced centrally and then shipped anywhere in the world to be fried locally.

Many snack products – for instance those highly flavoured crisp-type products that children enjoy – can be made on a simple single screw extruder but new products are being produced everyday which require more sophisticated and controlled production. A typical example would be crispbread and for this a twin-screw extruder would be used. Great accuracy would be required because the product was packaged and sold like a traditional biscuit or crispbread, so the manufacturer needed the greater flexibility that the twin-screw machine could bring. After being extruded, the crispbread would b cut into biscuit-sized pieces and then toasted top and bottom.

In volume terms, consumption of breakfast cereals appears to have accelerated during the 2000s. Certainly, consumption of oats, muesli and high-fibre cereals has expanded dramatically. Health is undoubtedly the key factor driving this expansion. Central to its success has been the enduring popularity of these products with children. Indeed around eight in ten children eat cereal for breakfast on a regular basis, making it an offering that is found in a large majority of households.

Portability and dining 'on-the-go' are the prevalent consumer demands/trends which have made space for cereals as an alternative from the traditional breakfast experience and the demand continues to increase. Two main segments make up the breakfast cereal market—hot and cold cereals.

Cold cereal is served dry, as snacks, or with cold milk, such as Corn Flakes, Shredded Wheat, or Cheerios. Cold cereal can be further separated into low, medium, and high-sugar segments. These three segments also mostly adhere to positioning of brands aimed at adults (low sugar), kids (high sugar), and a combination of both groups (medium sugar).

Hot cereal products are defined as cereal that must be cooked (on the stovetop or in the microwave oven) before eating, including such products as oatmeal, instant oatmeal, hot wheat, and other grain products.

Fluctuations will be evident as changes in consumer lifestyles, especially in terms of convenience, portability and health/diet trends, will continue to impact sales. Products that feature added health benefits and strong nutritional profiles will be well received. Overall, sales will likely be traded from one segment to another as shifts in consumer preferences arise. Therefore, its is of paramount importance that cereal manufacturers and distributors monitor and react to changing consumer lifestyles and eating habits.