Wheat (Triticum spp.) is the term used to designate the group of cereals , both cultivated and wild, that belong to the Triticum genus; they are annual plants of the grass family, widely cultivated throughout the world. The word wheat designates both the plant and its edible seeds, as is the case with the names of other cereals.
Origin
It is thought to have been cultivated for over 9,000 years. Some authors believe that it originated in the Nile River valley . Wheat entered America when Russian immigrants brought it to Kansas in 1873, the variety called Red Turkey , which grows better than any other.
Characteristics
Annual grass plant, from the grass family, with spikes from whose ground grains flour is obtained. Its scientific name is the genus triticum. It is one of the most widely used cereals in food production.
Floor
Wheat is best grown on soils with a lot of loam and clay, although yields are satisfactory on lighter soils. The increased yield compensates for the heavy nitrogen fertilisation.
Climate
Wheat thrives in subtropical, moderately temperate and moderately cool climates. Annual rainfall of 229-762 mm is most suitable, with more rainfall in spring than in summer. Average summer temperatures should be 13°C (56°F) or higher.
Production
Topping the list by volume of world wheat production are China , India , the United States , Russia , France and Canada , in that order.
Latin American countries appear as high as 14th place, with Argentina and Mexico at number 25. China’s volume in 1992 was 3.733 billion and Mexico’s in the same year was 115 million.
Supply
Sowing takes place in late autumn (winter wheat) or in spring (spring wheat). The sowing and harvesting times for wheat in the different producing countries depend naturally on the particular climatic conditions; in some countries wheat is harvested throughout the year.
However, the silage potential of most wheat-growing countries is sufficient to store most of the annual crop, so that the British flour manufacturer can buy wheat from any exporting country at almost any time of the year.
Classification
- Classification by harvest:
Wheat has 2 growing seasons: Winter wheat is planted in autumn and harvested in spring. It can be planted in places such as north-western Europe where the ground does not freeze excessively.
The grain germinates in autumn and grows slowly until spring. Frost may adversely affect young plants, but a layer of snow protects them and induces insulation.
Properties of wheat
Among the properties of wheat are:
- It is a food rich in carbohydrates that helps to obtain a lot of energy.
- Its richness in fiber makes it ideal for treating constipationor diverticula.
- It is ideal for nervous people or those studying due to its contribution of B vitamins.
- Its lignan (phytoestrogen) content reduces the possibility of suffering from breast, uterineor prostate cancer .
- Wheat has antioxidant properties as it is a good source of selenium and vitamin Ethat protect our cells against free radicals.
- Highly recommended for heart diseasedue to its richness in vitamin E, which helps prevent cholesterol from oxidizing and blocking arteries.
Nutritional value
Among the nutritional properties of wheat, it is worth highlighting that it has the following nutrients:
Nutrients | Worth |
Calories | 305 kcal. |
Fat | 0.14 g. |
Carbohydrates | 65 g. |
Proteins | 13 g. |
Fiber | 10 g. |
fats | 2 g. |
Calcium | 37 mg. |
Iron | 5 mg. |
Selenium | 55 mcg. |
Stages of the year
Spring wheat
It is planted in spring and harvested in early autumn. In places such as the Canadian prairies or the Russian steppes, which suffer from winters that are too harsh for winter sowing, wheat is sown in spring, as early as possible, so that the crop can be harvested before the autumn frosts set in.
The climatic characteristics of the areas where spring wheat is grown – maximum rainfall in spring and early summer and maximum temperatures in mid- and late summer – favour the production of fast-maturing grains with a glassy-textured endosperm and high protein content suitable for baking.
The production area of spring wheat is gradually expanding northwards in the northern hemisphere, with the introduction of new varieties grown for their rapid maturation characteristics.
Winter wheat
Grown in a climate with more constant temperature and rainfall, it matures more slowly, producing crops with higher yields and lower protein content, more suitable for biscuits and pastries than for baking. Classification according to the texture of the endosperm.
This grain characteristic is related to the way the grain is broken down during milling; the floury-vitreous character can be modified by the growing conditions. The development of the floury quality seems to be related to the maturation.
Vitreous wheat
The texture of the endosperm may be vitreous (waxy, stony, crystalline, horny). The specific weight of vitreous grains is generally greater than that of floury grains: 1.422 for vitreous grains (Bailey, 1916). The vitreous character is hereditary, but is also affected by environmental conditions. Thus: T. aegilopoides, T. dicoccoides, T. nionococcum and T. durum have vitreous grains.
Vitreous character can be induced by nitrogen manure or fertilizers and is positively correlated with high protein content; floury character is positively correlated with high grain yields. Grains are translucent and appear shiny against bright light. The vitreous endosperm lacks these fissures. Grains sometimes become floury as a result of some treatments, for example by repeated wetting and drying or by heat treatment.
Floury wheats
The texture of the endosperm is floury (starchy, chalky). The specific gravity of floury kernels is 1.405 (Bailey, 1916). Floury character is hereditary and affected by environmental conditions. Floury character is favored by heavy rains, light sandy soils and very dense planting and depends more on these conditions than on the type of grain grown. The opacity of floury kernels is an optical effect due to the presence of minute air-filled vacuoles or fissures between and perhaps within the endosperm cells. The fissures form interior reflecting surfaces that impede the transmission of light and give the endosperm a white appearance. Floury kernels are characteristic of varieties that grow slowly and have a long maturation period.
Classification according to endosperm hardness
Hardness and softness are milling characteristics related to the way the endosperm breaks up. In hard wheats, the breakage tends to occur along the lines that limit the cells, while the endosperm of soft wheats breaks up unexpectedly and at random.
This phenomenon suggests areas of mechanical strength and weakness in durum wheat, and fairly uniform weakness in soft wheat. One view is that hardness is related to the degree of adhesion between starch and protein.
Another way of looking at it is that hardness depends on the degree of continuity of the protein matrix (Stenvert and Kingswood, 1977). Hardness affects how easily the bran is separated from the endosperm. In hard wheat, the endosperm cells separate more cleanly and tend to remain intact, whereas in soft wheat, the cells tend to fragment, falling off while part of the cells remain attached to the bran.