Key points

• There are many different types of cereal grains, each having unique properties
• Most cereals are processed to form other  foods or ingredients
• Cereals and cereal products are an important source of energy, carbohydrate, protein and fibre.

They also contain a range of micronutrients such as vitamin E, some of the B vitamins, sodium, magnesium and zinc. 

Cereals are the edible seeds or grains of the grass family.  Each cereal has unique properties which make it suitable for a variety of food products. Cereals are also known as ‘staple foods’ as they often make up the bulk of the diet since they are relatively cheap to produce.

Storage: Cereals should be kept in a cool dry place. They are prone to infestation by insects if kept for long periods of time.

Types

Wheat is usually ground to flour which is used to produce a wide range of products. The type of flour produced differs according to the rate of extraction. Cous cous and cracked wheat or bulgur are also made from wheat. 

Maize (or corn) may be processed to make many different ingredients (e.g. high fructose corn syrup which can be used as an alternative to sucrose  derived from sugar cane and sugar beet and food products. It may be milled in a similar process to wheat. Its germ is rich in oil, and can be refined to produce corn oil.

Barley is mainly sold as pearl barley, which is the whole grain with its husk removed. It is also used in bread (as flour) and ground as porridge in some countries.

Brown rice has its outer husk removed, and white rice is milled and polished further to remove the bran and germ. There are many different types of rice, categorised by size, shape and the region where they are grown. Rice can be ground to make flour.

Rye contains little gluten, so produces breads with low volume and a dense texture, although in Russia, Poland, Germany and Scandinavian countries it is the major bread grain. Rye is also used to produce crispbread and alcohol.

Oats are rolled rather than crushed during processing. Coarse, medium and fine grades of oatmeal are available and are used for porridge and oatcakes, while rolled oats are used for porridge, and oat flour is used for baby foods and for ready-to-eat (RTE) breakfast cereals.

Millet is the name used for a number of different small-grained cereal grasses, e.g. pearl, finger (or ragi), proso and foxtail millet. These crops are important in parts of Africa and Asia.

There are several other cereals which have an important role in certain parts of the world.

For example:

• Buckwheat  is eaten as a cooked grain, as porridge or is used in pancakes  in parts of Russia
• Quinoa is used in Chile and Peru to make bread Gelatinisation (thickening): When a  flour (wheat, corn, rye or rice) is added to a liquid, the starch granules swell on heating. This causes the granules to rupture and starch is released into the liquid. The starch granules absorb liquid, causing the sauce to thicken. Pearl barley may also be used to thicken a soup or casserole. The swollen barley grains will remain contributing to the texture of the casserole.

Processing: Cereals undergo a range of processes, the most common being milling, which affect their technological and nutritional properties. Generally, the final nutrient content of a cereal will depend on the extent to which the outer layers are removed during processing, as this is where the fibre, vitamins and minerals tend to be concentrated.

Products: Cereals are processed and used to produce a range of products, e.g.

breakfast cereals, bread and pasta. Some nutrients are lost during this processing but are added at a later stage known as ‘restoration’ .

Protein: The amount of protein in each cereal differs (from 6-15% protein) and this affects the final product. Bread, with its characteristic open texture and appearance, relies on high protein flour, e.g. strong wheat flour. In products such as cakes, biscuits and pastry, lower wheat flours are used to produce crumbly and light textures.

Cereals and cereal products are an important source of energy, carbohydrate, protein and fibre. They also contain a range of micronutrients such as vitamin E, some of the B vitamins, sodium, magnesium and zinc. Because of the fortification of some cereal products they also contribute significant amounts of calcium and iron.

There is evidence to suggest that regular consumption of cereals, specifically wholegrains, may have a role in the prevention of chronic diseases. The strength of evidence varies and although cause and effect has not currently been established, people who consume diets rich in wholegrain cereals seem to have a lower incidence of many chronic diseases, e.g. coronary heart disease and type 2 diabetes. It remains to be established whether this is a direct effect, or whether wholegrain consumption is merely a marker of a healthy lifestyle or some other factor.

© British Nutrition Foundation 2004