Sugar beet
A sugar beet is a plant whose root contains a high concentration of sucrose and is grown commercially for sugar production. In plant breeding, it is known as the Altissima cultivar group of the common beet. Together with other beet cultivars, such as beetroot and chard, it belongs to the subspecies Beta vulgaris subsp. vulgaris but is classified as var. saccharifera. Its closest wild relative is the sea beet.
Sugar beets are grown in climates that are too cold for sugarcane. In 2024, Russia and Germany were the two largest sugar beet producers contributing to a world total of 294 million tonnes. Sugarcane accounts for most of the rest of sugar produced globally.
Description
The sugar beet has a conical, white, fleshy root with a flat crown. The plant consists of the root and a rosette of leaves. Sugar is formed by photosynthesis in the leaves and is then stored in the root.The root of the beet contains 75% water, about 20% sugar, and 5% pulp. The exact sugar content can vary between 12% and 21%, depending on the cultivar and growing conditions. Sugar is the primary value of sugar beet as a cash crop. The pulp, insoluble in water and mainly composed of cellulose, hemicellulose, lignin, and pectin, is used in animal feed. The byproducts of the sugar beet crop, such as pulp and molasses, add another 10% to the value of the harvest.
Sugar beets grow exclusively in the temperate zone, in contrast to sugarcane, which grows exclusively in the tropical and subtropical zones. The average weight of a sugar beet ranges between. Sugar beet foliage has a rich, brilliant green color and grows to a height of about. The leaves are numerous and broad and grow in a tuft from the crown of the beet, which is usually level with or just above the ground surface.
History
Discovery
The species beet consists of several cultivar groups. The 16th-century French scientist Olivier de Serres discovered a process for preparing sugar syrup from beetroot. He wrote: "The beet-root, when being boiled, yields a juice similar to syrup of sugar, which is beautiful to look at on account of its vermilion colour". Because crystallized cane sugar was already available and had a better taste, this process did not become popular.Modern sugar beets date to the mid-18th century Silesia, where Frederick the Great, king of Prussia, subsidized experiments to develop processes for sugar extraction. In 1747, Andreas Sigismund Marggraf, professor of physics in the Academy of Science of Berlin, isolated sugar from beetroots and found them at concentrations of 1.3–1.6%. He also demonstrated that the sugar that could be extracted from beets was identical to that produced from cane. He found the best of these vegetable sources for sugar was the white beet. Despite Marggraf's success in isolating sugar from beets, it did not lead to commercial beet sugar production.
Development of the sugar beet
Marggraf's student and successor Franz Karl Achard began plant breeding sugar beet in Kaulsdorf near Berlin in 1786. Achard started his plant breeding by evaluating 23 varieties of beet for sugar content. In the end he selected a local strain from Halberstadt in modern-day Saxony-Anhalt, Germany. Moritz Baron von Koppy and his son further selected white, conical tubers from this strain. The selection was named weiße schlesische Zuckerrübe, meaning white Silesian sugar beet. In about 1800, this cultivar contained about 5% to 6% sucrose by weight. It went on to become the progenitor of all modern sugar beets. The plant breeding process has continued since then, leading to a sucrose content of around 18% in modern varieties.Beet sugar industry
Franz Karl Achard opened the world's first beet sugar factory in 1801, at Kunern, Silesia. The idea to produce sugar from beet was soon introduced to France, whence the European sugar beet industry rapidly expanded. By 1840, about 5% of the world's sugar was derived from sugar beets, and by 1880, this number had risen more than tenfold to over 50%. In North America, the first commercial production started in 1879 at a farm in Alvarado, California. The sugar beet was introduced to Chile by German settlers around 1850.Culture
The sugar beet, like sugarcane, needs a particular soil and a proper climate for its successful cultivation. The most important requirements are that the soil must contain a large supply of nutrients, be rich in humus, and be able to contain a great deal of moisture. A certain amount of alkali is not necessarily detrimental, as sugar beets are not especially susceptible to injury by some alkali. The ground should be fairly level and well-drained, especially where irrigation is practiced.Generous crops can be grown in both sandy soil and heavy loams, but the ideal soil is a sandy loam, i.e., a mixture of organic matter, clay and sand. A subsoil of gravel, or the presence of hardpan, is not desirable, as cultivation to a depth of from is necessary to produce the best results.
Climatic conditions, temperature, sunshine, rainfall and winds have an important bearing upon the success of sugar beet agriculture. A temperature ranging from during the growing months is most favorable. In the absence of adequate irrigation, of rainfall are necessary to raise an average crop. High winds are harmful, as they generally crust the land and prevent the young beets from coming through the ground. The best results are obtained along the coast of southern California, where warm, sunny days succeeded by cool, foggy nights seem to meet sugar beet's favored growth conditions. Sunshine of long duration but not of great intensity is the most important factor in the successful cultivation of sugar beets. Near the equator, the shorter days and the greater heat of the sun sharply reduce the sugar content in the beet.
In high elevation regions such as those of Idaho, Colorado and Utah, where the temperature is high during the daytime, but where the nights are cool, the quality of the sugar beet is excellent. In Michigan, the long summer days from the relatively high latitude and the influence of the Great Lakes result in satisfactory climatic conditions for sugar beet culture. Sebewaing, Michigan, lies in the Thumb region of Michigan; both the region and state are major sugar beet producers. Sebewaing is home to one of four Michigan Sugar Company factories. The town sponsors an annual Michigan Sugar Festival.
To cultivate beets successfully, the land must be properly prepared. Deep ploughing is the first principle of beet culture. It allows the roots to penetrate the subsoil without much obstruction, thereby preventing the beet from growing out of the ground, besides enabling it to extract considerable nourishment and moisture from the lower soil. If the latter is too hard, the roots will not penetrate it readily and, as a result, the plant will be pushed up and out of the earth during the process of growth. A hard subsoil is impervious to water and prevents proper drainage. It should not be too loose, however, as this allows the water to pass through more freely than is desirable. Ideally, the soil should be deep, fairly fine and easily penetrable by the roots. It should also be capable of retaining moisture and at the same time admit of a free circulation of air and good drainage. Sugar beet crops exhaust the soil rapidly. Crop rotation is recommended and necessary. Normally, beets are grown in the same ground every third year, peas, beans or grain being raised the other two years.
In most temperate climates, beets are planted in the spring and harvested in the autumn. At the northern end of its range, growing seasons as short as 100 days can produce commercially viable sugar beet crops. In warmer climates, such as in California's Imperial Valley, sugar beets are a winter crop, planted in the autumn and harvested in the spring. In recent years, Syngenta has developed the so-called tropical sugar beet. It allows the plant to grow in tropical and subtropical regions. Beets are planted from a small seed; of beet seed comprises 100,000 seeds and will plant over of ground followed behind, and would lift the beet and swiftly chop the crown and leaves from the root with a single action. Working this way, he would leave a row of beets that could be forked into the back of a cart.
Today, mechanical sowing, herbicide application for weed control, and mechanical harvesting have displaced this reliance on manual farm work. A root beater uses a series of blades to chop the leaf and crown from the root. The beet harvester lifts the root, and removes excess soil from the root in a single pass over the field. A modern harvester is typically able to cover six rows at the same time. The beets are dumped into trucks as the harvester rolls down the field, and then delivered to the factory. The conveyor then removes more soil.
If the beets are to be left for later delivery, they are formed into clamps. Straw bales are used to shield the beets from the weather. Provided the clamp is well built with the right amount of ventilation, the beets do not significantly deteriorate. Beets that freeze and then defrost, produce complex carbohydrates that cause severe production problems in the factory. In the UK, loads may be hand examined at the factory gate before being accepted.
In the US, the fall harvest begins with the first hard frost, which arrests photosynthesis and the further growth of the root. Depending on the local climate, it may be carried out over the course of a few weeks or be prolonged throughout the winter months. The harvest and processing of the beet is referred to as "the campaign", reflecting the organization required to deliver the crop at a steady rate to processing factories that run 24 hours a day for the duration of the harvest and processing. In the Netherlands, this period is known as de bietencampagne, a time to be careful when driving on local roads in the area while the beets are being grown, because the naturally high clay content of the soil tends to cause slippery roads when soil falls from the trailers during transport.