Saturday, January 15, 2022

Shredded wheat processing

Shredded wheat was the first mass-produced, ready-to-eat cereal, invented at a time when people typically ate a cooked breakfast. The steps involved in producing whole-grain shredded cereal are grain cleaning, cooking, cooling and tempering, shredding, biscuit formation, biscuit baking, and packaging.
White wheat produces shredded wheat biscuits that are light in color with a golden-brown top and bottom crust when properly baked. Red wheat can also be used for shredding, but the shreds are more gray.

The raw kernels are hard as rock, so to soft them up, the factory cooks them simultaneously in water and with steam for about 30 minutes. Cooking is typically performed in batches with excess water at temperatures slightly below the boiling point at atmospheric pressure.

Cooking is achieved and stopped when the very center of the kernel endosperm turns from starchy white to translucent gray. Its moisture content is about 50%.

After the completion of the cooking cycle, the water is drained from the cooker, and the wheat is conveyed to cooling units.

The wheat travels through a dryer. Inside. Nozzles blast the soggy kernels with hot air. About 10 minutes later, the cooked kernels are dried.

The conveyor belt transports them to the operation that puts the shredded in shredded wheat. The wheat goes into several fill tubes. Each fill tube drops kernels in a between two rollers that apply pressure shredding the kernels into delicate strands. The shredding process squeezes the wheat kernels between one roll with a smooth surface and another roll with a grooved surface. The strands drop onto the conveyor belt below, forming a fairly even layer.

Each pair of shredding rollers deposits another layer of strands in top of the previous one, until there’s a specific number of stacked layers.

After the web of many layers of shreds reaches the end of the shredder, it is fed through a cutting device to form the individual biscuits. The edges of the cutting device are dull, rather than sharp, so that the cutting action compresses the edges of the biscuit together to form a crimped joint, which holds the shreds together in biscuit form.

A special designed cutter that gives the sheet of layered wheat strands into rectangular biscuits. Biscuits then travels through a tunnel oven for approximately 10 minutes.

Next steps baking and toasting. During baking process, the temperatures are in the range of 200 to 315 °C. The moisture content of biscuits going into the oven is usually about 45% and the final moisture content out of the oven is about 4%.

The next machine compresses the sheets with a belt, which breaks apart the individual biscuits.

For frosted shredded wheat
To make the frosting, they blend and heat sugar, water and other ingredients. Overhead nozzles spray it into the passing biscuits. The frosting takes about a minute to dry and set.
Shredded wheat processing

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