Oats processing: Cleaning

Mill processing starts with the arrival of oats from the farm or storage facility. The miller only accepts oats that will yield flakes of satisfactory quality and will attempt to maximize profits by estimating the potential yield.

Oats arrive at the mill via bulk railcar or truck and are sampled to ensure suitable quality for milling. Once the grain is deemed acceptable, the oats enter the mill, they pass under a magnetic separator to remove foreign metal objects.

The oats are then cleaned, mainly on the basis of physical properties of the grain. Sieves are used to remove contaminants on the basis of size.

The cleaning process utilizes several devices to take advantage of particular physical properties of the grain.

The oats experience a series of rotating or oscillating screens that can both retain large objects (such as straw, sticks and stone) and let small objects such as underdeveloped oats, dirt, weed seeds and dust to pass through. The retained oat stream is then subjected to aspiration to remove more of the light materials.

This is followed by a dry stoner that removes high-density but similar-sized particles such as rocks and other grains, such as maize.
Oats processing: Cleaning

Oats cleaning process

As with numerous agricultural products, harvesting oats will lead to co-mingling of the oats with other components found in the field and transportation process, and these foreign materials need to be removed to make oats suitable for human consumption.

Cleaning removes the unwanted materials – such as corn, soybeans, foreign material, weed seeds, wheat, or barley – from the milling quality oats.

The oats are brought at harvest into the mill by the growers. The miller only accepts oats that will yield flakes of satisfactory quality, and will attempt to maximise profits by estimating the potential yield and looking at the price of the oats and any possible added value obtainable. The oats then cleaned and dried so that they may be safely stored until they are needed. When the oats enter the mill, they pass under a magnetic separator to remove foreign metal objects, a very common practice in many food-processing operations.

The they are cleaned, taking off straws, stones and weed seeds and are then sent through a stream of air to remove any dust or light grains that would be unsuitable for milling.

This is followed by a dry stoner that removes high-density but similar-sized particles such as rocks and other grains, such as maize.

Even high quality oat grain will require cleaning to ensure that only sound oats are processed. The oats must appear wholesome and clean, must be free from extraneous material, with large and light coloured oats that give a high yield being preferred.

Oats cleaning process 

Cleaning process of the grain

Grain cleaning reduces the problems that occur during storage and handling. Clean grains save storage space and increase marketability.

Over the years there has been rapid development of machinery for grain cleaning. The one most often used employ the air screen system, which was the basis for the oldest cleaning machines and still is the easiest and most effective form of cleaning bulk grain.

The mill is the point where cereals are transformed from agricultural commodities to foods or food ingredients.

Physical cleaning takes place in the mill to remove straw and chaff, stones, soil and metal fragments, which could damage the mill, damaged or ergot-infected grains, seed other than the cereal grain required, insects and other foreign matter.

In preparing wheat cleaning, the wheat is blown into hopper scales that record the quantity of uncleaned wheat. Some of the coarser impurities are removed by this process.

The grain then passed over a series of coarse and fine sieves that further remove contaminating materials, including chaff and straw.

The various dry cleaning processed used in modern four mills have little effect on the microbiological condition of the grain.

The efficiency of the cleaning operation is dependent on the efficiency of the machine, the selection of appropriate screens for the particular task and the competence of the operator.
Cleaning process of the grain

Wheat cleaning and milling

Before the wheat reaches the milling stage, first it has undergo several preliminary operations that ensure the correct of the main process. The first of these is wheat cleaning.

Wheat is passed through a series of machines that apply the principles of particle size and density separation.

Foreign materials such as metal, sticks, stones, straw, seeds and other grain are removed in steps by a magnetic separator, vibrating screens, a destoner, a disc separator and a scourer.

Sieves remove contaminants larger than wheat kernels as well as finer contaminants such as sand. In addition, air is used to remove plant material that is lighter than the grain.

After cleaning, the wheat is tempered prior to be milled. In this stage, the moisture content of the grain is increased by adding water and by allowing the grain to sit for a period of time.

Wheat is milled to remove the bran and germ and reduce the wheat kernel to flour to be used in various baked and nonbaked goods.

In general, 100 pounds of wheat will produce 72 pounds of flour. The aimed of white flour milling is to extract a maximum amount do endosperm from the wheat berry in as pure a form as possible.

The wheat is passed through a series of machines to break open the wheat kernels and reducing of the endosperm by grinding to obtain the final product – plain flour.

Additives of less than 1 weight % are added to the flour by a mixing process.

Family four for retail sale is packed in 5, 10, or 25 pound bags. Bakery flour may be packed in 50 or 100 pound bags or shipped in bulk trucks or railcars.

Wheat cleaning and milling