Common wheat
Field with wheat
Common wheat ( Triticum aestivum), also known as bread wheat or wheat seed, a plant species within the Gramineae family is ( Poaceae ). The hexaploid cereal species common wheat (Triticum aestivum) is one of the oldest cultivated plants and originated around 9000 years ago ( 7000 BC ) the crossing of tetraploid emmer wheat (Triticum dicoccum ) and diploid goat grass ( Aegilops tauschii ).
Soft wheat is the most economically important species of wheat and is used for making bread, other baked goods, malt, feed, used for starch production etc.. In contrast to the durum wheat ( Triticum durum) he has a significantly softer, mehligeres grain and a lower protein content.
Description
The wheat is grown as a winter or summer cereal and then grows as a winter annual, annual herbaceous plant - known in the jargon Therophyt. It reaches heights of growth from 40 to 100 cm, rarely to 150 cm. The blade is thin-walled and hollow. The nodes ( more nodes ) are bald or balding early. The 6 to 16 mm wide, Leaf blades are hairy at first soft and later often bare and rough.
The eared inflorescence is 6-18 cm long, while at least three times as long as wide, without awns. It is tight and square in cross section. The ears axis is not fragile, so it is a naked wheat. The point of attachment of the spikelet has no tufts of hair. At the top of the axis distances between the spikelets 4-8 mm in size. The spikelets are three-to sechsblütig, about the same length as wide. Fertil, the lower three to five flowers. The glumes are about 10 mm long, they only have at the top of a keel, they are rounded down. The keel terminates in a short, blunt tooth. The lemmas are awnless and have a short tooth, or they have a 15 cm long awn. Pollination is by foreign or self-pollination.
The fruit is loosely wrapped to fruit maturity of the cover and palea and falls out. The endosperm is floury or vitreous. Germination occurs only at temperatures above 4 ° C.
For common wheat chromosome base number is x = 7, it is hexaploid, the chromosome number is 6n = 42
Origin
The earliest finds of common wheat are from the reference Can Hasan in the Central Anatolian province of Karaman from the 7th millennium BC. The result is Triticum aestivum with six sets of chromosomes AABBDD from the (crossing) of tetraploid AABB Emmer (Triticum dicoccum ) and diploid goat grass DD ( Aegilops tauschii ).
Genome
The genome of the common wheat consists of 17 billion base pairs ( 17 Gigabasenpaare ) and includes 94000-96000 genes, which are spread over 6 sets of chromosomes.
Cultivation and use
Soft wheat is used as a bread grain for the production of baked goods, and for the production of malt (wheat beer). When grinding is a byproduct of the wheat bran, which serves as a power feed in animal fattening, but is also used as food.
A smaller proportion of soft and hard wheat is used industrially for starch production. Other cereals have a greater importance, such as corn, dates from the 80 % of the cereal starch produced worldwide, while wheat starch accounts for nine percent here. Because soft wheat with about 70 % has a higher starch content than durum wheat with 60 %, it is more suitable for industrial use. In addition to this strength also includes the production of bioethanol. In Germany, approximately five percent of wheat production were used for extraction of starch and starch derivatives in 2007 at 1.03 million tonnes.
Due to the temporary strong price increase in 2007 / 08, the industrial use of renewable raw wheat had taken ( for example, ethanol and starch) something. By now return to higher production and lower prices, an increase in global industrial use of wheat by six percent to 18 million tons expected for 2008/ 09. In a world wheat production of about 690 million tons (2008), this corresponds to almost three percent.
Average composition
The composition of common wheat fluctuates naturally, both depending on the environmental conditions (soil, climate ) as well as the cultivation techniques (fertilization, crop protection).
Information per 100 g edible portion:
* Difference Calculation ** In some countries often have higher values 1 semi-essential 1 mg = 1000 ug
The physiological calorific value is 1263 kJ per 100 g edible portion.
For common wheat for baking purposes in Germany different quality levels can be distinguished. Important parameters are the volume yield in the rapid mix test (RMT, a standardized test baking ), the protein content, the number of cases and other quality characteristics. The division of the German Federal Office of Plant Varieties comprises the steps of:
- E -Weizen ( wheat Elite )
- A wheat ( wheat quality, also called Aufmischweizen )
- B- wheat (bread wheat)
- C- wheat (other wheat)
Documents
- Siegmund Seybold (ed.): Schmeil Fitschen - interactive ( CD -Rom ), Quelle & Meyer, Wiebelsheim 2001/2002, ISBN 3-494-01327-6