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The following article was sourced from a Wikipedia page at the following address: SUGAR
Sugar is the generalized name for sweet, short-chain, soluble carbohydrates, many of which are used in food. They are carbohydrates, composed of carbon, hydrogen, and oxygen. There are various types of sugar derived from different sources. Simple sugars are called monosaccharides and include glucose (also known as dextrose), fructose and galactose. The table or granulated sugar most customarily used as food is sucrose, a disaccharide. (In the body, sucrose hydrolyses into fructose and glucose.) Other disaccharides include maltose and lactose. Longer chains of sugars are called oligosaccharides. Chemically-different substances may also have a sweet taste, but are not classified as sugars. Some are used as lower-calorie food substitutes for sugar described as artificial sweeteners. Sugars are found in the tissues of most plants, but are present in sufficient concentrations for efficient extraction only in sugarcane and sugar beet. Sugarcane refers to any of several species of giant grass in the genus Saccharum that have been cultivated in tropical climates in South Asia and Southeast Asia since ancient times. A great expansion in its production took place in the 18th century with the establishment of sugar plantations in the West Indies and Americas. This was the first time that sugar became available to the common people, who had previously had to rely on honey to sweeten foods. Sugar beet, a cultivated variety of Beta vulgaris, is grown as a root crop in cooler climates and became a major source of sugar in the 19th century when methods for extracting the sugar became available. Sugar production and trade have changed the course of human history in many ways, influencing the formation of colonies, the perpetuation of slavery, the transition to indentured labour, the migration of peoples, wars between sugar-trade–controlling nations in the 19th century, and the ethnic composition and political structure of the new world. The world produced about 168 million tonnes of sugar in 2011. The average person consumes about 24 kilograms (53 lb) of sugar each year (33.1 kg in industrialised countries), equivalent to over 260 food calories per person, per day. Since the latter part of the twentieth century, it has been questioned whether a diet high in sugars, especially refined sugars, is good for human health. Sugar has been linked to obesity, and suspected of, or fully implicated as a cause in the occurrence of diabetes, cardiovascular disease, dementia, macular degeneration, and tooth decay. Numerous studies have been undertaken to try to clarify the position, but with varying results, mainly because of the difficulty of finding populations for use as controls that do not consume or are largely free of any sugar consumption. HISTORY Ancient times and Middle Ages
Sugar has been produced in the Indian subcontinent since ancient times. It was not plentiful or cheap in early times and honey was more often used for sweetening in most parts of the world. Originally, people chewed raw sugarcane to extract its sweetness. Sugarcane was a native of tropical South Asia and Southeast Asia. Different species seem to have originated from different locations with Saccharum barberi originating in India and S. edule and S. officinarum coming from New Guinea. One of the earliest historical references to sugarcane is in Chinese manuscripts dating back to 8th century BC that state that the use of sugarcane originated in India. Sugar remained relatively unimportant until the Indians discovered methods of turning sugarcane juice into granulated crystals that were easier to store and to transport. Crystallized sugar was discovered by the time of the Imperial Guptas, around the 5th century AD. In the local Indian language, these crystals were called khanda, which is the source of the word candy. Indian sailors, who carried clarified butter and sugar as supplies, introduced knowledge of sugar on the various trade routes they travelled. Buddhist monks, as they travelled around, brought sugar crystallization methods to China. During the reign of Harsha (r. 606–647) in North India, Indian envoys in Tang China taught methods of cultivating sugarcane after Emperor Taizong of Tang (r. 626–649) made known his interest in sugar. China then established its first sugarcane plantations in the seventh century. Chinese documents confirm at least two missions to India, initiated in 647 AD, to obtain technology for sugar refining. In South Asia, the Middle East and China, sugar became a staple of cooking and desserts. The triumphant progress of Alexander the Great was halted on the banks of the Indus River by the refusal of his troops to go further east. They saw people in the Indian subcontinent growing sugarcane and making granulated, salt-like sweet powder, locally called Sharkara, pronounced as saccharum. On their return journey, the Macedonian soldiers carried the "honey-bearing reeds" home with them. Sugarcane remained a little-known crop in Europe for over a millennium, sugar a rare commodity, and traders in sugar wealthy. Crusaders brought sugar home with them to Europe after their campaigns in the Holy Land, where they encountered caravans carrying "sweet salt". Early in the 12th century, Venice acquired some villages near Tyre and set up estates to produce sugar for export to Europe, where it supplemented honey, which had previously been the only available sweetener. Crusade chronicler William of Tyre, writing in the late 12th century, described sugar as "very necessary for the use and health of mankind". In the 15th century, Venice was the chief sugar refining and distribution centre in Europe. Modern history
In August 1492, Christopher Columbus stopped at La Gomera in the Canary Islands, for wine and water, intending to stay only four days. He became romantically involved with the governor of the island, Beatriz de Bobadilla y Ossorio, and stayed a month. When he finally sailed, she gave him cuttings of sugarcane, which became the first to reach the New World. The Portuguese took sugar to Brazil. By 1540, there were 800 cane sugar mills in Santa Catarina Island and there were another 2,000 on the north coast of Brazil, Demarara, and Surinam. The first sugar harvest happened in Hispaniola in 1501; and, many sugar mills had been constructed in Cuba and Jamaica by the 1520s. Sugar was a luxury in Europe prior to the 18th century, when it became more widely available. It then became popular and by the 19th century, sugar came to be considered a necessity. This evolution of taste and demand for sugar as an essential food ingredient unleashed major economic and social changes. It drove, in part, colonization of tropical islands and nations where labour-intensive sugarcane plantations and sugar manufacturing could thrive. The demand for cheap labour to perform the hard work involved in its cultivation and processing increased the demand for the slave trade from Africa (in particular West Africa). After slavery was abolished, there was high demand for indentured labourers from South Asia (in particular India). Millions of slave and indentured labourers were brought into the Caribbean and the Americas, Indian Ocean colonies, southeast Asia, Pacific Islands, and East Africa and Natal. The modern ethnic mix of many nations that have been settled in the last two centuries has been influenced by the demand for sugar. Sugar also led to some industrialization of former colonies. For example, Lieutenant J. Paterson, of the Bengal establishment, persuaded the British Government that sugar cane could be cultivated in British India with many advantages and at less expense than in the West Indies. As a result, sugar factories were established in Bihar in eastern India. During the Napoleonic Wars, sugar beet production increased in continental Europe because of the difficulty of importing sugar when shipping was subject to blockade. By 1880, the sugar beet was the main source of sugar in Europe. It was cultivated in Lincolnshire and other parts of England, although the United Kingdom continued to import the main part of its sugar from its colonies. Until the late nineteenth century, sugar was purchased in loaves, which had to be cut using implements called Sugar nips. In later years, granulated sugar was more usually sold in bags. Sugar cubes were produced in the nineteenth century. The first inventor of a process to make sugar in cube form was Moravian Jakub Kryštof Rad, director of a sugar company in Dačice. He began sugar cube production after being granted a five-year patent for the invention on January 23, 1843. Henry Tate of Tate & Lyle was another early manufacturer of sugar cubes at his refineries in Liverpool and London. Tate purchased a patent for sugar cube manufacture from German Eugen Langen, who in 1872 had invented a different method of processing of sugar cubes. CHEMISTRY
Sucrose: a disaccharide of glucose (left) and fructose (right), important molecules in the body Scientifically, sugar loosely refers to a number of carbohydrates, such as monosaccharides, disaccharides, or oligosaccharides. Monosaccharides are also called "simple sugars," the most important being glucose. Almost all sugars have the formula CnH2nOn (n is between 3 and 7). Glucose has the molecular formula C6H12O6. The names of typical sugars end with ose, as in "glucose", "dextrose", and "fructose". Sometimes such words may also refer to any types of carbohydrates soluble in water. The acyclic mono- and disaccharides contain either aldehyde groups or ketone groups. These carbon-oxygen double bonds (C=O) are the reactive centres. All saccharides with more than one ring in their structure result from two or more monosaccharides joined by glycosidic bonds with the resultant loss of a molecule of water (H2O) per bond. Monosaccharides in a closed-chain form can form glycosidic bonds with other monosaccharides, creating disaccharides (such as sucrose) and polysaccharides (such as starch). Enzymes must hydrolyze or otherwise break these glycosidic bonds before such compounds become metabolized. After digestion and absorption the principal monosaccharides present in the blood and internal tissues include glucose, fructose, and galactose. Many pentoses and hexoses can form ring structures. In these closed-chain forms, the aldehyde or ketone group remains non-free, so many of the reactions typical of these groups cannot occur. Glucose in solution exists mostly in the ring form at equilibrium, with less than 0.1% of the molecules in the open-chain form.
Natural polymers of sugars
Flammability
TYPES OF SUGAR
Monosaccharides Glucose, dextrose or grape sugar occurs naturally in fruits and plant juices and is the primary product of photosynthesis. Most ingested carbohydrates are converted into glucose during digestion and it is the form of sugar that is transported around the bodies of animals in the bloodstream. It can be manufactured from starch by the addition of enzymes or in the presence of acids. Glucose syrup is a liquid form of glucose that is widely used in the manufacture of foodstuffs. It can be manufactured from starch by enzymatic hydrolysis. Fructose or fruit sugar occurs naturally in fruits, some root vegetables, cane sugar and honey and is the sweetest of the sugars. It is one of the components of sucrose or table sugar. It is used as a high-fructose syrup, which is manufactured from hydrolyzed corn starch that has been processed to yield corn syrup, with enzymes then added to convert part of the glucose into fructose. In general, galactose does not occur in the free state but is a constituent with glucose of the disaccharide lactose or milk sugar. It is less sweet than glucose. It is a component of the antigens found on the surface of red blood cells that determine blood groups.
Disaccharides Sucrose is found in the stems of sugar cane and roots of sugar beet. It also occurs naturally alongside fructose and glucose in other plants, in particular fruits and some roots such as carrots. The different proportions of sugars found in these foods determines the range of sweetness experienced when eating them. A molecule of sucrose is formed by the combination of a molecule of glucose with a molecule of fructose. After being eaten, sucrose is split into its constituent parts during digestion by a number of enzymes known as sucrases. Maltose is formed during the germination of certain grains, the most notable being barley, which is converted into malt, the source of the sugar's name. A molecule of maltose is formed by the combination of two molecules of glucose. It is less sweet than glucose, fructose or sucrose. It is formed in the body during the digestion of starch by the enzyme amylase and is itself broken down during digestion by the enzyme maltase. Lactose is the naturally occurring sugar found in milk. A molecule of lactose is formed by the combination of a molecule of galactose with a molecule of glucose. It is broken down when consumed into its constituent parts by the enzyme lactase during digestion. Children have this enzyme but some adults no longer form it and they are unable to digest lactose. SOURCES The sugar contents of common fruits and vegetables are presented in Table 1. All data with a unit of g (gram) are based on 100 g of a food item. The fructose/glucose ratio is calculated by dividing the sum of free fructose plus half sucrose by the sum of free glucose plus half sucrose. PRODUCTION Sugar beet
Sugar beet (Beta vulgaris) is a biennial plant in the Family Amaranthaceae, the tuberous root of which contains a high proportion of sucrose. It is cultivated in temperate regions with adequate rainfall and requires a fertile soil. The crop is harvested mechanically in the autumn and the crown of leaves and excess soil removed. The roots do not deteriorate rapidly and may be left in a clamp in the field for some weeks before being transported to the processing plant. Here the crop is washed and sliced and the sugar extracted by diffusion. Milk of lime is added to the raw juice and carbonatated in a number of stages in order to purify it. Water is evaporated by boiling the syrup under a vacuum. The syrup is then cooled and seeded with sugar crystals. The white sugar that crystallizes out can be separated in a centrifuge and dried. It requires no further refining.
Sugarcane Refining
Refined sugar is made from raw sugar that has undergone a refining process to remove the molasses. Raw sugar is a sucrose which is synthesized from sugar cane or sugar beet and cannot immediately be consumed before going through the refining process to produce refined sugar or white sugar. The sugar may be transported in bulk to the country where it will be used and the refining process often takes place there. The first stage is known as affination and involves immersing the sugar crystals in a concentrated syrup that softens and removes the sticky brown coating without dissolving them. The crystals are then separated from the liquor and dissolved in water. The resulting syrup is treated either by a carbonatation or by a phosphatation process. Both involve the precipitation of a fine solid in the syrup and when this is filtered out, many of the impurities are removed at the same time. Removal of colour is achieved by using either a granular activated carbon or an ion-exchange resin. The sugar syrup is concentrated by boiling and then cooled and seeded with sugar crystals, causing the sugar to crystallize out. The liquor is spun off in a centrifuge and the white crystals are dried in hot air and ready to be packaged or used. The surplus liquor is made into refiners' molasses. The International Commission for Uniform Methods of Sugar Analysis sets standards for the measurement of the purity of refined sugar, known as ICUMSA numbers; lower numbers indicate a higher level of purity in the refined sugar.
Refined sugar is widely used for industrial needs for higher quality. Refined sugar is purer (ICUMSA below 300) than raw sugar (ICUMSA over 1,500). The level of purity associated with the colours of sugar, expressed by standard number ICUMSA (International Commission for Uniform Methods of sugar Analysis), the smaller ICUMSA numbers indicate that higher purity of sugar.
Producing countries FORMS AND USES
Granulated sugars are used at the table to sprinkle on foods and to sweeten hot drinks and in home baking to add sweetness and texture to cooked products. They are also used as a preservative to prevent micro-organisms from growing and perishable food from spoiling as in jams, marmalades, and candied fruits. Milled sugars (known as powdered sugar and confectioner's sugar) are ground to a fine powder. They are used as icing sugar, for dusting foods and in baking and confectionery. Screened sugars are crystalline products separated according to the size of the grains. They are used for decorative table sugars, for blending in dry mixes and in baking and confectionery. Brown sugars are granulated sugars with the grains coated in molasses to produce a light, dark, or demerara sugar. They are used in baked goods, confectionery, and toffees. Sugar cubes (sometimes called sugar lumps) are white or brown granulated sugars lightly steamed and pressed together in block shape. They are used to sweeten drinks. Liquid sugars are strong syrups consisting of 67% granulated sugar dissolved in water. They are used in the food processing of a wide range of products including beverages, ice cream, jams, and hard candy. Invert sugars and syrups are blended to manufacturers specifications and are used in breads, cakes, and beverages for adjusting sweetness, aiding moisture retention and avoiding crystallization of sugars. Syrups and treacles are dissolved invert sugars heated to develop the characteristic flavours. Treacles have added molasses. They are used in a range of baked goods and confectionery including toffees and liquorice. Low-calorie sugars and sweeteners are often made of maltodextrin with added sweeteners. Maltodextrin is an easily digestible synthetic polysaccharide consisting of short chains of glucose molecules and is made by the partial hydrolysis of starch. The added sweeteners are often aspartame, saccharin, stevia, or sucralose. Polyols are sugar alcohols and are used in chewing gums where a sweet flavour is required that lasts for a prolonged time in the mouth. In winemaking, fruit sugars are converted into alcohol by a fermentation process. If the must formed by pressing the fruit has a low sugar content, additional sugar may be added to raise the alcohol content of the wine in a process called chaptalization. In the production of sweet wines, fermentation may be halted before it has run its full course, leaving behind some residual sugar that gives the wine its sweet taste. Molasses is commonly used to make rum, and sugar byproducts are used to make ethanol for fuel. CONSUMPTION In most parts of the world, sugar is an important part of the human diet, making food more palatable and providing food energy. After cereals and vegetable oils, sugar derived from sugar cane and beet provided more kilocalories per capita per day on average than other food groups. According to the FAO, an average of 24 kilograms (53 lb) of sugar, equivalent to over 260 food calories per day, was consumed annually per person of all ages in the world in 1999. Even with rising human populations, sugar consumption is expected to increase to 25.1 kilograms (55 lb) per person per year by 2015. Data collected in multiple nationwide surveys between 1999 and 2008 show that the intake of added sugars has declined by 24 percent with declines occurring in all age, ethnic and income groups. The per capita consumption of refined sugar in the United States has varied between 27 and 46 kilograms (60 and 101 lb) in the last 40 years. In 2008, American per capita total consumption of sugar and sweeteners, exclusive of artificial sweeteners, equalled 61.9 kilograms (136 lb) per year. This consisted of 29.65 kg (65.4 lb) pounds of refined sugar and 31 kg (68.3 lb) pounds of corn-derived sweeteners per person. HEALTH EFFECTS Some studies involving the health impact of sugars are effectively inconclusive. The WHO and FAO meta studies have shown directly contrasting impacts of sugar in refined and unrefined forms and since most studies do not use a population that do not consume any "free sugars" at all, the baseline is effectively flawed. Hence, there are articles such as Consumer Reports on Health that stated in 2008, "Some of the supposed dietary dangers of sugar have been overblown. Many studies have debunked the idea that it causes hyperactivity, for example".
Blood glucose levels
Obesity and diabetes
Cardiovascular disease The consumption of added sugars has been positively associated with multiple measures known to increase cardiovascular disease risk amongst adolescents as well as adults. Studies are suggesting that the impact of refined carbohydrates or high glycemic load carbohydrates are more significant than the impact of saturated fatty acids on cardiovascular disease. A high dietary intake of sugar (in this case, sucrose or disaccharide) can substantially increase the risk of heart and vascular diseases. According to a Swedish study of 4301 people undertaken by Lund University and Malmö University College, sugar was associated with higher levels of bad blood lipids, causing a high level of small and medium low-density lipoprotein (LDL) and reduced high-density lipoprotein (HDL). In contrast, the amount of fat eaten did not affect the level of blood fats. Incidentally quantities of alcohol and protein were linked to an increase in the good HDL blood fat.
Alzheimer's disease
Tooth decay Also, studies have shown that the consumption of sugar and starch have different impacts on oral health with the ingestion of starchy foods and fresh fruit being associated with low levels of dental caries.
Addiction
Hyperactivity MEASUREMENTS Different culinary sugars have different densities due to differences in particle size and inclusion of moisture. Domino Sugar gives the following weight to volume conversions (in United States customary units):
Another source gives different values for the bulk densities:
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