Until leavened bread and baking ovens became commonplace in Europe, porridge was a typical means of preparing cereal crops for the table.
This has happened twice in the ancient history of wheat, the first time, about 30,000 years ago, to produce Emmer Wheat, and the second time, about 9,000 years ago, to produce the wheat we use today
Wheat in Ancient Daily Life
Sprouted Emmer Wheat may have been the main ingredient of ancient Egyptian beer. Whether it was Emmer Wheat or barley, though, Egyptian beer was one of the daily essentials, along with bread and onions. [See Ancient Brewing.] The ancient Greek diet had similar essentials: bread, oil, and wine. [See The Staple Articles of Food.] In Deuteronomy 8, the promised land promises wheat before honey:
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8:7 For the LORD thy God bringeth thee into a good land, a land of
brooks of water, of fountains and depths that spring out of valleys and
hills;
8:8 A land of wheat, and barley, and vines, and fig trees, and pomegranates; a land of oil olive, and honey;
8:9 A land wherein thou shalt eat bread without scarceness, thou shalt not lack any thing in it; a land whose stones are iron, and out of whose hills thou mayest dig brass.
This grain is grown on more land area than any other commercial food.[citation needed] World trade in wheat is greater than for all other crops combined.[4] Globally, wheat is the leading source of vegetable protein in human food, having a higher protein content than other major cereals, maize (corn) or rice.[5] In terms of total production tonnages used for food, it is currently second to rice as the main human food crop and ahead of maize, after allowing for maize's more extensive use in animal feeds.
Wheat was a key factor enabling the emergence of city-based societies at the start of civilization because it was one of the first crops that could be easily cultivated on a large scale, and had the additional advantage of yielding a harvest that provides long-term storage of food. Wheat contributed to the emergence of city-states in the Fertile Crescent, including the Babylonian and Assyrian empires. Wheat grain is a staple food used to make flour for leavened, flat and steamed breads, biscuits, cookies, cakes, breakfast cereal, pasta, noodles, couscous[6] and for fermentation to make beer,[7] other alcoholic beverages,[8] or biofuel.[9]
Wheat is planted to a limited extent as a forage crop for livestock, and its straw can be used as a construction material for roofing thatch.[10][11] The whole grain can be milled to leave just the endosperm for white flour. The by-products of this are bran and germ. The whole grain is a concentrated source of vitamins, minerals, and protein, while the refined grain is mostly starch.
Origin
Cultivation of wheat began to spread beyond the Fertile Crescent after about 8000 BCE. Jared Diamond traces the spread of cultivated emmer wheat starting in the Fertile Crescent about 8500 BCE. Archaeological analysis of wild emmer indicates that it was first cultivated in the southern Levant with finds at Iran dating back as far as 9600 BCE.[16][17] Genetic analysis of wild einkorn wheat suggests that it was first grown in the Karacadag Mountains in southeastern Turkey. Dated archeological remains of einkorn wheat in settlement sites near this region, including those at Abu Hureyra in Syria, suggest the domestication of einkorn near the Karacadag Mountain Range.[18] With the anomalous exception of two grains from Iraq ed-Dubb, the earliest carbon-14 date for einkorn wheat remains at Abu Hureyra is 7800 to 7500 years BCE.[19]
Remains of harvested emmer from several sites near the Karacadag Range have been dated to between 8600 (at Cayonu) and 8400 BCE (Abu Hureyra), that is, in the Neolithic period. With the exception of Iraq ed-Dubb, the earliest carbon-14 dated remains of domesticated emmer wheat were found in the earliest levels of Tell Aswad, in the Damascus basin, near Mount Hermon in Syria. These remains were dated by Willem van Zeist and his assistant Johanna Bakker-Heeres to 8800 BCE. They also concluded that the settlers of Tell Aswad did not develop this form of emmer themselves, but brought the domesticated grains with them from an as yet unidentified location elsewhere.[20]
The cultivation of emmer reached Greece, Cyprus and India by 6500 BCE, Egypt shortly after 6000 BCE, and Germany and Spain by 5000 BCE.[21] "The early Egyptians were developers of bread and the use of the oven and developed baking into one of the first large-scale food production industries." [22] By 3000 BCE, wheat had reached England and Scandinavia. A millennium later it reached China. The first identifiable bread wheat (Triticum aestivum) with sufficient gluten for yeasted breads has been identified using DNA analysis in samples from a granary dating to approximately 1350 BCE at Assiros in Greek Macedonia.[23]
Wheat continued to spread throughout Europe. In England, wheat straw (thatch) was used for roofing in the Bronze Age, and was in common use until the late 19th century.[24]
The State Emblem of the Soviet Union featured a wreath made of wheat.
Farming techniques
Yields of pure wheat per unit area increased as methods of crop rotation were applied to long cultivated land, and the use of fertilizers became widespread. Improved agricultural husbandry has more recently included threshing machines and reaping machines (the 'combine harvester'), tractor-drawn cultivators and planters, and better varieties (see Green Revolution and Norin 10 wheat). Great expansion of wheat production occurred as new arable land was farmed in the Americas and Australia in the 19th and 20th centuries.
Genetics
Wheat genetics is more complicated than that of most other domesticated species. Some wheat species are diploid, with two sets of chromosomes, but many are stable polyploids, with four sets of chromosomes (tetraploid) or six (hexaploid).[25]- Einkorn wheat (T. monococcum) is diploid (AA, two complements of seven chromosomes, 2n=14).[1]
- Most tetraploid wheats (e.g. emmer and durum wheat) are derived from wild emmer, T. dicoccoides. Wild emmer is itself the result of a hybridization between two diploid wild grasses, T. urartu and a wild goatgrass such as Aegilops searsii or Ae. speltoides. The unknown grass has never been identified among now surviving wild grasses, but the closest living relative is Aegilops speltoides.[citation needed] The hybridization that formed wild emmer (AABB) occurred in the wild, long before domestication,[25] and was driven by natural selection.
- Hexaploid wheats evolved in farmers' fields. Either domesticated emmer or durum wheat hybridized with yet another wild diploid grass (Aegilops tauschii) to make the hexaploid wheats, spelt wheat and bread wheat.[25] These have three sets of paired chromosomes, three times as many as in diploid wheat.
Wild grasses in the genus Triticum and related genera, and grasses such as rye have been a source of many disease-resistance traits for cultivated wheat breeding since the 1930s.[26]
Heterosis, or hybrid vigor (as in the familiar F1 hybrids of maize), occurs in common (hexaploid) wheat, but it is difficult to produce seed of hybrid cultivars on a commercial scale (as is done with maize) because wheat flowers are perfect and normally self-pollinate. Commercial hybrid wheat seed has been produced using chemical hybridizing agents; these chemicals selectively interfere with pollen development, or naturally occurring cytoplasmic male sterility systems. Hybrid wheat has been a limited commercial success in Europe (particularly France), the USA and South Africa.[27] F1 hybrid wheat cultivars should not be confused with the standard method of breeding inbred wheat cultivars by crossing two lines using hand emasculation, then selfing or inbreeding the progeny many (ten or more) generations before release selections are identified to be released as a variety or cultivar.
Synthetic hexaploids made by crossing the wild goatgrass wheat ancestor Aegilops tauschii and various durum wheats are now being deployed, and these increase the genetic diversity of cultivated wheats.[28][29][30]
Stomata (or leaf pores) are involved in both uptake of carbon dioxide gas from the atmosphere and water vapor losses from the leaf due to water transpiration. Basic physiological investigation of these gas exchange processes has yielded valuable carbon isotope based methods that are used for breeding wheat varieties with improved water-use efficiency. These varieties can improve crop productivity in rain-fed dry-land wheat farms.[31]
In 2010, a team of UK scientists funded by BBSRC announced they had decoded the wheat genome for the first time (95% of the genome of a variety of wheat known as Chinese Spring line 42).[32] This genome was released in a basic format for scientists and plant breeders to use but was not a fully annotated sequence which was reported in some of the media.[33]
On 29 November 2012, whole-genome sequence of bread wheat has been published.[34] Random shotgun libraries of total DNA and cDNA from the T. aestivum cv. Chinese Spring (CS42) were sequenced in Roche 454 pyrosequencer using GS FLX Titanium and GS FLX+ platforms to generate 85 Gb of sequence (220 million reads), equivalent to 5X genome coverage and identified between 94,000 and 96,000 genes.[34]
The wheat whole genome sequence data provides direct access to all 96,000 genes and represents an essential step towards a systematic understanding of biology and engineering the cereal crop for valuable traits. Its implications in cereal genetics and breeding includes the examination of genome variation, association mapping using natural populations, performing wide crosses and alien introgression, studying the expression and nucleotide polymorphism in transcriptomes, analyzing population genetics and evolutionary biology, and studying the epigenetic modifications. Moreover, the availability of large-scale genetic markers generated through NGS technology will facilitate trait mapping and make marker-assisted breeding much feasible.[35]
Moreover, the WGS data not only facilitate in deciphering the complex phenomena such as heterosis and epigenetics, it may also enable breeders to predict which fragment of a chromosome is derived from which parent in the progeny line, thereby recognizing crossover events occurring in every progeny line and inserting markers on genetic and physical maps without ambiguity. In due course, this will assist in introducing specific chromosomal segments from one cultivar to another. Besides, the researchers had identified diverse classes of genes participating in energy production, metabolism and growth that were probably linked with crop yield, which can now be utilized for the development of transgenic wheat. Thus whole genome sequence of wheat and the availability of thousands of SNPs will inevitably permit the breeders to stride towards identifying novel traits, providing biological knowledge and empowering biodiversity-based breeding.[35]
Plant breeding
Main article: Physiological and molecular wheat breeding
F1 hybrid wheat cultivars should not be confused with wheat cultivars deriving from standard plant breeding. Heterosis or hybrid vigor (as in the familiar F1 hybrids of maize) occurs in common (hexaploid) wheat, but it is difficult to produce seed of hybrid cultivars on a commercial scale as is done with maize because wheat flowers are complete and normally self-pollinate.[36] Commercial hybrid wheat seed has been produced using chemical hybridizing agents, plant growth regulators that selectively interfere with pollen development, or naturally occurring cytoplasmic male sterility systems. Hybrid wheat has been a limited commercial success in Europe (particularly France), the United States and South Africa.[37]
The major breeding objectives include high grain yield, good quality, disease and insect resistance and tolerance to abiotic stresses include mineral, moisture and heat tolerance. The major diseases in temperate environments include the following, arranged in a rough order of their significance from cooler to warmer climates: eyespot, Stagonospora nodorum blotch (also known as glume blotch), yellow or stripe rust, powdery mildew, Septoria tritici blotch (sometimes known as leaf blotch), brown or leaf rust, Fusarium head blight, tan spot and stem rust. In tropical areas, spot blotch (also known as Helminthosporium leaf blight) is also important.
Wheat has also been the subject of mutation breeding, with the use of gamma, x-rays, ultraviolet light, and sometimes harsh chemicals. The varieties of wheat created through this methods are in the hundreds (varieties being as far back as 1960), more of them being created in higher populated countries such as China.[38]
Hulled versus free-threshing wheat
Naming
For more details on this topic, see Taxonomy of wheat.
Within a species, wheat cultivars are further classified by wheat breeders and farmers in terms of:
- Growing season, such as winter wheat vs. spring wheat.[11]
- Protein content. Bread wheat protein content ranges from 10% in some soft wheats with high starch contents, to 15% in hard wheats.
- The quality of the wheat protein gluten. This protein can determine the suitability of a wheat to a particular dish. A strong and elastic gluten present in bread wheats enables dough to trap carbon dioxide during leavening, but elastic gluten interferes with the rolling of pasta into thin sheets. The gluten protein in durum wheats used for pasta is strong but not elastic.
- Grain color (red, white or amber). Many wheat varieties are reddish-brown due to phenolic compounds present in the bran layer which are transformed to pigments by browning enzymes. White wheats have a lower content of phenolics and browning enzymes, and are generally less astringent in taste than red wheats. The yellowish color of durum wheat and semolina flour made from it is due to a carotenoid pigment called lutein, which can be oxidized to a colorless form by enzymes present in the grain.
Einkorn wheat (from German Einkorn, literally "single grain") can refer either to the wild species of wheat, Triticum boeoticum, or to the domesticated form, Triticum monococcum. The wild and domesticated forms are either considered separate species, as here, or as subspecies of T. monococcum. Einkorn is a diploid species of hulled wheat, with tough glumes ('husks') that tightly enclose the grains. The cultivated form is similar to the wild, except that the ear stays intact when ripe and the seeds are larger.
inkorn wheat is one of the earliest cultivated forms of wheat, alongside emmer wheat (T. dicoccum). Grains of wild einkorn have been found in Epi-Paleolithic sites of the Fertile Crescent. It was first domesticated approximately 7500 BC (7050 BC ≈ 9000 BP), in the Pre-Pottery Neolithic A (PPNA) or B (PPNB) periods.[1] Evidence from DNA finger-printing suggests einkorn was domesticated near Karaca Dağ in southeast Turkey, an area in which a number of PPNB farming villages have been found.[2] Its cultivation decreased in the Bronze Age, and today it is a relict crop that is rarely planted, though it has found a new market as a health food. It remains as a local crop, often for bulgur (cracked wheat) or as animal feed, in mountainous areas of France, Morocco, the former Yugoslavia, Turkey and other countries. It often survives on poor soils where other species of wheat fail.[3]
Einkorn is an ancient grain, and is known as the
oldest variety of "wheat." Einkorn is also sometimes referred to as "farro" or "farro
einkorn." Einkorn was first cultivated 5,000 to 10,000 years
ago. It is classified as a "diploid" because it only has two sets of
chromosomes. Modern wheat varieties are classified as "hexaploid," having six
sets of chromosomes, due to a long history of hybridization.
Einkorn is thought to have originated in the upper area of the fertile crescent
of the Near East (Tigris-Euphrates regions), and is quite probably the main
grain recorded in the earliest biblical history.
Einkorn became widely distributed throughout the Near East, Transcaucasia, the
Mediterranean region, southwestern Europe, and the Balkans, and was one of the
first cereals cultivated for food.
Another ancient grain, emmer, has four sets of chromosomes and was probably an early
hybrid of wild einkorn that was more suitable for a wider range of climates and
geographical areas, particularly warmer climates. Emmer became the predominant
wheat throughout the Near and Far East, Europe and northern Africa until about
4,000-1,000 BCE, although it was still cultivated in isolated regions such as
south-central Russia into the last century, and even today remains an important
crop in Ethiopia and a minor crop in Italy and India.
The oldest hexaploid grain and the predecessor to modern wheat is probably spelt. Spelt was
a hybrid of emmer with more adaptability then emmer. These three ancient grains
are known as "the covered wheats," since the kernels do not thresh free of their hard
coverings, making them more labor intensive to mill. These ancient grains went
through a long history of hybridizations to make them easier to mill and
process into our modern day wheat, and to make them more desirable for bread making with a higher gluten content.
But due to gluten toxicity issues in modern times, many are reviving the ancient
varieties of grains, and einkorn is the oldest.
Nutritional Characteristics of Einkorn
The ancient grain einkorn (triticum
monococcum) is packed with
nutrition. It is a rich source of the beta carotene lutein, a powerful
antioxidant. Einkorn has the highest amounts of lutein of any other variety of
wheat. Einkorn is also a rich source of tocotrienols and tocopherols, powerful
antioxidants and forms of Vitamin E. Compared to modern wheat varieties, einkorn
has higher
levels of protein, crude fat, phosphorous, and potassium.
Gluten and Toxicity
Since einkorn is such an ancient grain and the
only known diploid classified variety of wheat still known to exist today, there has been
considerable interest in the issue of gluten toxicity. One way of measuring
gluten toxicity is by the gliadin to glutenin ratio, and einkorn has a much more favorable ratio than
modern wheat varieties. Einkorn has a gliadin to glutenin ratio of 2:1 compared
to 0.8:1 for durum and hard red wheat. While this lower gluten ratio may hold
some promise for gluten intolerance disorders, it should
be cautioned that einkorn DOES contain gluten, and so those desiring to avoid
all gluten are NOT recommended to consume einkorn.
Emmer was widely cultivated in Mesopotamia (contemporary Middle East)and later adopted by the Romans. Other forms of wheat eventually replaced emmer as they had higher yields and husks that could be removed without pounding or grinding. Emmer wheat is especially popular in Italy (called farro). It is used in a number of ways in Italian cooking, but is most popular boiled whole and served like a risotto. It is also used to make pastas
Einkorn is even older than emmer, believed to be one of the earliest recorded grains in the Bible, known as shippon in Hebrew. It provides a rich source of beta-carotene(lutein), a powerful antioxidant.
Both emmer and einkorn are high in protein, fiber, and minerals. Since these wheats have a gluten structure different from modern wheat, it is a good alternative for people with gluten allergies. That being said, einkorn and emmer do contain gluten, and so those desiring to avoid gluten altogether are not recommended to consume these wheats. Consult with your doctor to see if einkorn or emmer wheat is safe for you.
Since gluten allergies are becoming so predominant in modern times, many people are now turning to einkorn and emmer—including chefs themselves—as healthy and delicious wheat choices.
"Here are seven fun facts I learned about the nutritional content and health benefits of einkorn wheat:
- Wheat gluten studies have found einkorn wheat may be non-toxic to suffers of gluten intolerance and celiacs disease
- Einkorn wheat has 14 chromosomes while modern wheats have 42 (Friendly to the body’s digestive system)
- Einkorn contains 3 to 4 times more beta-carotene than modern wheats (Boosts immunity, helps prevent cancer and heart disease)
- Einkorn contains 35 times more Vitamin A than modern wheats (Healthy eyes, reproductive organs and prevention of many cancers)
- Einkorn contains 3 to 4 times more lutein than modern wheats (Prevention of macular degeneration and cataracts)
- Einkorn contains 4-5 times more riboflavin than modern wheats (Used by the body to create energy and is an antioxidant that slows aging)
- Einkorn is a “hulled” wheat, whereas modern wheats are not. The hull can protect the grain from stray chemical contamination and insects making it an easier grain to grow ORGANICALLY!"
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History of Wheat domestication
Event Year People were collecting and eating wild Emmer Wheat in the Near East (as well as barley). Evidence for this comes from the finding of wild Emmer Wheat seeds in an archaeological site on the shores of the Sea of Galilee in Israel. c 17000 BC People were collecting and eating wild Einkorn Wheat in the Near East and were probably doing so well before this. Evidence from this stems from the finding of carbonised remains of wild Einkorn Wheat seeds in archaeological sites in northern Syria. Seeds of the wild forms can be distinguised from the domesticated forms because they are thinner in appearance. c10000 BC People had domesticated hulled Emmer Wheat through selection of plants with plumper seeds than wild forms which were non-brittle so they were retained during harvesting and only shed through the threshing process. Evidence for this comes from the occurrence of plump Emmer Wheat seeds at an archaeological site near Damascus in Israel. Emmer Wheat was the main cereal crop in the Near East from the very beginnings of agriculture in this region. It also came to be cultivated further afield in the Aegean region (e.g. Greece), on the Balkan Peninsula and in central Europe and remained the main cereal crop through the Neolithic period and into the Bronze Age although Einkorn Wheat was often grown as well. c 7800 BC Einkorn Wheat had been domesticated through selection and propagation of plants with plumper seeds than wild forms. Evidence for this domestication comes from finding these plumper seeds at archaeological sites in Syria, Turkey and Iran. With time Einkorn Wheat becomes a major crop in the near East in the Neolithic period. It spread further than this in the Neolithic period to Cyprus, Greece, the Balkan Peninsula, Europe and the Caucasus. For instance, domesticated Einkorn has been found in in Greek agricultural settlements dating back to 6000-6500 BC. c7000 BC Selection of free-threshing, naked, forms of Emmer Wheat has been successful although hulled Emmer and Einkorn continue to be grown. However, by the Late Bronze Age, growing of naked wheats predominated in the Mediterranean and Near East regions. Durum Wheat is derived from these naked wheat types. 6000-7000 BC Earliest record of people using Bread Wheat (the hulled Spelta variety). This occurred in the Caucasus region between the Black and Caspian Seas which makes sense because this is within the main geographical distribution of Aegilops squarrosa which is the grass that at some stage formed a fertile hybrid with cultivated Emmer Wheat to form Bread Wheat. Free-threshing, naked, Bread Wheat is thought to have developed soon afterwards (before 4000 BC).
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