Breakfast cereals have become a signature part of many people’s pantries. Cereal is a quick, effortless, and tasty meal or snack. All you need is a bowl, the cereal, and maybe some milk. Hot cereals require a little more patience, but the cooking process is still conveniently simple. These foods are staples for many families, but not many people know how breakfast cereals are made. In short, an industrial web food processing system uses metal rollers, ovens, and cooking extruders to turn field grains into the finished product.
From the Field to the Factory
- The factory receives the whole grains, which are then inspected and cleaned.
- Metal rollers crush the grains to remove the hull, or exterior shell. The crushed grain may get crushed again to form a flour.
- The crushed grains are mixed with flavorings, vitamins, sweeteners, salt, and water in a rotating cylinder. The time, temperature, and speed depend on the type of grain.
- Once cooked, the grain is transferred to a conveyor belt and passes through a drying oven, where any remaining water mixes with the grain to form a soft, shapeable mass.
- Flours pass through a cooking extruder, where a long screw mixes the flour with water, flavorings, salt, sweeteners, vitamins, and food coloring. The mixture is also cooked through this process.
- Once the cooked flour mixture passes through the extruder, it emerges as a long ribbon, which is then cut into pellets. These are processed the same as the cooked grains.
- The cooked grains and pellets are tempered (cooled) for several hours and then flattened between industrial rollers. The pressure of these rollers results in flakes, which are conveyed to ovens.
- Once in the oven, the flakes are blasted with hot air to remove moisture and to toast them to the desired color and flavor.
- The cooked grains and pellets are sent to an oven, where they are puffed with hot air. Typically, rice is used for puffed cereals, but any grain can be cooked, cooled, and dried.
- From there, the grains are rolled between metal rollers, which partially flattens or bumps them. Afterward, the grains are dried again and sent to an oven to swell.
- Gun-puffing is also used to puff rice and wheat cereals. The wheat must be soaked in saltwater so that it can be broken into large pieces. The grain is placed in the gun, where it’s exposed to hot steam and high pressure. The gun drastically reduces the pressure, causing the puffing reaction.
- Cooked grains and pellets—typically wheat—cook in boiling water to allow moisture. Afterward, it cools and is then rolled between two metal rollers, one smoothed and one grooved. A metal comb shreds the grain and drops the ribbons onto a conveyor belt.
- From there, the ribbons are stacked into layers, which are cut into the proper size and baked for color and dryness.
Granola and Others
- A cooking extruder can shape the grains into any design after the initial converting process. Rotating blades cut the ribbons into the proper shape. Granolas and mixed cereals undergo a similar process. Oats and other grains are mixed with nuts, fruits, flavorings, sweeteners, and salt before they’re cooked on a conveyor belt. This belt moves through an oven, where an intense, dry heat crumbles the mixture to the desired size.
- Hot cereals, such as oatmeal, farina, and grits, are processed similarly, but they’re only partially cooked so that customers can fully cook them quickly and conveniently.
From the Factory to the Store
- Once the cereals have gone through the manufacturing stage, extra coatings such as vitamins, minerals, sweeteners, flavorings, frostings, or syrups may be added.
- After the cereals cool for a final time, they’re ready for packaging. The packaging usually involves a plastic bag that goes into a cardboard box, or the cereal may go directly into a cardboard box.
- The bag is tightly heat-sealed, and the box is shut with a weak adhesive for easy opening. The boxes are then packed into cartons for shipping to retailers.