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Sugar

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Image:Sugar 2xmacro.jpg
Magnification of grains of sugar, showing their monoclinic hemihedral crystalline structure.
Sugar, granulated
Nutritional value per 100 g (3.5 oz)
Energy 390 kcal   1620 kJ
Carbohydrates     99.98 g
- Sugars  99.91 g
- Dietary fiber  0 g  
Fat 0 g
Protein 0 g
Water 0.03 g
Riboflavin (Vit. B2)  0.019 mg   1%
Calcium  1 mg 0%
Iron  0.01 mg 0%
Potassium  2 mg   0%
Percentages are relative to US
recommendations for adults.
Source: USDA Nutrient database
Sugars, brown
Nutritional value per 100 g (3.5 oz)
Energy 380 kcal   1580 kJ
Carbohydrates     97.33 g
- Sugars  96.21 g
- Dietary fiber  0 g  
Fat 0 g
Protein 0 g
Water 1.77 g
Thiamin (Vit. B1)  0.008 mg   1%
Riboflavin (Vit. B2)  0.007 mg   0%
Niacin (Vit. B3)  0.082 mg   1%
Vitamin B6  0.026 mg 2%
Folate (Vit. B9)  1 μg  0%
Calcium  85 mg 9%
Iron  1.91 mg 15%
Magnesium  29 mg 8% 
Phosphorus  22 mg 3%
Potassium  346 mg   7%
Sodium  39 mg 3%
Zinc  0.18 mg 2%
Percentages are relative to US
recommendations for adults.
Source: USDA Nutrient database
Magnified crystals of refined sugar.
Magnified crystals of refined sugar.

Sugar (the word stems from the Sanskrit sharkara) consists of a class of edible crystalline substances including sucrose, lactose, and fructose. Human taste-buds interpret its flavor as sweet. Sugar as a basic food carbohydrate primarily comes from sugar cane and from sugar beet, but also appears in fruit, honey, sorghum, sugar maple (in maple syrup), and in many other sources. It forms the main ingredient in much candy. Excessive consumption of sugar has been associated with increased incidences of type-2 diabetes, obesity and tooth-decay.

Contents

Terminology

Popular

In non-scientific use, the term sugar refers to sucrose (also called "table sugar" or "saccharose") — a white crystalline solid disaccharide. In this informal sense, the word "sugar" principally refers to crystalline sugars.

Humans most commonly use sucrose as their sugar of choice for altering the flavor and properties (such as mouthfeel, preservation, and texture) of beverages and food. Commercially-produced table-sugar comes either from sugar cane or from sugar beet. Manufacturing and preparing food may involve other sugars, including palm sugar and fructose, generally obtained from corn (maize) or from fruit.

Sugar may dissolve in water to form a syrup. A great many foods exist which principally contain dissolved sugar. Generically known as "syrups", they may also have other more specific names such as "honey" or "molasses".

Scientific

Scientifically, sugar refers to any monosaccharide or disaccharide. Monosaccharides (also called "simple sugars"), such as glucose, store chemical energy which biological cells convert to other types of energy.

In a list of ingredients, any word that ends with "ose" will likely denote a sugar. Sometimes such words may also refer to any types of carbohydrates soluble in water.

Glucose (a type of sugar found in human blood-plasma) has the molecular formula C6 H12 O6.

Culinary/nutritional

In culinary terms, the foodstuff known as sugar delivers a primary taste sensation of sweetness. Apart from the many forms of sugar and of sugar-containing foodstuffs, alternative non-sugar-based sweeteners exist, and these particularly attract interest from people who have problems with their blood-sugar level (such as diabetics) and people who wish to limit their calorie-intake while still enjoying sweet foods. Both natural and synthetic substitutes exist with no significant carbohydrate (and thus low-calorie) content: for instance stevia (a herb), and saccharin (produced from naturally occurring but not necessarily naturally edible substances by inducing appropriate chemical reactions).

History

Early use of sugar-cane in Asia

Originally, people chewed the cane raw to extract its sweetness. Later, the Indians discovered how to crystallize sugar during the Gupta dynasty, around 350 AD.[1] John F. Robyt (1998) locates the two most probable origins of sugar cultivation as North East India or the South Pacific, which provide evidence of sugarcane cultivation as early as 10,000 BC and 6,000 BC respectively.[2] Further archaeological evidence associates sugar with the Indus valley.[2]

This cultivation spread to the Indian subcontinent during early antiquity.[1] Sugar culture spread from India to China, and from China it spread even further.[2] However, sugar remained relatively unimportant until the Indians discovered methods of turning sugarcane juice into granulated crystals which would prove easier to store and to transport.[1] Indian sailors, consumers of clarified butter and sugar, spread this food through various trade routes.[1] In South Asia, the Middle East and China, sugar became a staple of cooking and desserts.

Some evidence suggests that the Greeks under Alexander the Great may have taken sugar from India during their retreat.[3] It would later spread to Europe and to Africa.[3]

Early refining methods involved grinding or pounding the cane in order to extract the juice, and then boiling down the juice or drying it in the sun to yield sugary solids that looked like gravel. The Sanskrit word for "sugar" (sharkara), also means "gravel". Similarly, the Chinese use the term "gravel sugar" (Traditional Chinese: 砂糖) for table sugar.

Cane sugar outside Asia

Image:Evstafiev-zafra.jpg
A sugar-cane cutter in Cuba.

During the Muslim Agricultural Revolution, Arab entrepreneurs adopted the techniques of sugar production from India and then refined and transformed them into a large-scale industry. Arabs set up the first sugar mills, refineries, factories and plantations. The Arabs and Berbers diffused sugar throughout the Arab Empire and beyond across much of the Old World, including Western Europe after they conquered the Iberian Peninsula in the 8th century AD.[4] Crusaders also brought sugar home with them to Europe after their campaigns in the Holy Land, where they encountered caravans carrying "sweet salt". Crusade chronicler William of Tyre, writing in the late 12th century, described sugar as "very necessary for the use and health of mankind".

The 1390s saw the development of a better press, which doubled the juice obtained from the cane. This permitted economic expansion of sugar plantations to Andalucia and to the Algarve. The 1420s saw sugar-production extended to the Canary Islands, Madeira and the Azores.

In August 1492 Christopher Columbus stopped at 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, Beatrice de Bobadilla, and stayed a month. When he finally sailed she gave him cuttings of sugar-cane, which became the first to reach the New World.

The Portuguese took sugar to Brazil. Hans Staden, published in 1555, writes that by 1540 Santa Catalina Island had 800 sugar-mills and that the north coast of Brazil, Demarara and Surinam had another 2000. Approximately 3000 small mills built before 1550 in the New World created an unprecedented demand for cast iron gears, levers, axles and other implements. Specialist trades in mold-making and iron-casting developed in Europe due to the expansion of sugar-production. Sugar-mill construction developed technological skills needed for a nascent industrial revolution in the early 17th-century.[citation needed]

After 1625 the Dutch carried sugar-cane from South America to the Caribbean islands — where it became grown from Barbados to the Virgin Islands. The years 1625 to 1750 saw sugar become worth its weight in gold.[citation needed] Contemporaries often compared[citation needed] the worth of sugar with valuable commodities including musk, pearls, and spices. Prices declined slowly as production became multi-sourced, especially through British colonial policy. Formerly an indulgence of the rich, sugar became increasingly common among the poor. Sugar-production increased in mainland North American colonies, in Cuba, and in Brazil. African slaves became the dominant source of plantation-workers, as they proved resistant to the diseases of malaria and yellow fever. (European indentured servants remained in shorter supply, susceptible to disease and overall forming a less economic investment. European diseases such as smallpox had reduced the numbers of local Native Americans.) But replacement of Native American with African slaves also occurred because of the high death-rates on sugar-plantations. The British West Indies imported almost 4 million slaves, but had only 400,000 Blacks left after slavery ended in the British Empire in 1838.

With the European colonization of the Americas, the Caribbean became the world's largest source of sugar. These islands could supply sugar-cane using slave-labor and produce sugar at prices vastly lower than those of cane-sugar imported from the East. Thus the economies of entire islands such as Guadaloupe and Barbados became based on sugar-production. By 1750 the French colony known as Saint-Domingue (subsequently the independent country of Haiti) became the largest sugar-producer in the world. Jamaica too became a major producer in the 18th century. Sugar-plantations fueled a demand for manpower; between 1701 and 1810 ships brought nearly one million slaves to work in Jamaica and in Barbados.

During the eighteenth century, sugar became enormously popular and the sugar-market went through a series of booms. The heightened demand and production of sugar came about to a large extent due to a great change in the eating habits of many Europeans. For example, they began consuming jams, candy, tea, coffee, cocoa, processed foods, and other sweet victuals in much greater numbers. Reacting to this increasing craze, the islands took advantage of the situation and began producing more sugar. In fact, they produced up to ninety percent of the sugar that the western Europeans consumed. Some islands proved more successful than others when it came to producing the product. And in Barbados and the British Leeward Islands sugar provided 93% and 97% respectively of exports.

Planters later began developing ways to boost production even more. For example, they began using more manure when growing their crops. They also developed more advanced mills and began using better types of sugar-cane. Despite these and other improvements, the price of sugar reached soaring heights, especially during events such as the revolt against the Dutch[citation needed] and the Napoleonic Wars. Sugar remained in high demand, and the islands' planters knew exactly how to take advantage of the situation.

As Europeans established sugar-plantations on the larger Caribbean islands, prices fell, especially in Britain. By the eighteenth century all levels of society had become common consumers of the former luxury product. At first most sugar in Britain went into tea, but later confectionery and chocolates became extremely popular. Many Britons (especially children) also ate jams.[citation needed] Suppliers commonly sold sugar in solid cones and consumers required a sugar nip, a pliers-like tool, to break off pieces.

Sugar-cane quickly exhausts the soil in which it grows, and planters pressed larger islands with fresher soil into production in the nineteenth century. In this century, for example, Cuba rose to become the richest land in the Caribbean (with sugar as its dominant crop) because it formed the only major island land-mass free of mountainous terrain. Instead, nearly three-quarters of its land formed a rolling plain — ideal for planting crops. Cuba also prospered above other islands because Cubans used better methods when harvesting the sugar crops: they adopted modern milling-methods such as water-mills, enclosed furnaces, steam-engines, and vacuum-pans. All these technologies increased productivity.

After the Haïtian Revolution established the independent state of Haiti, sugar production in that country declined and Cuba replaced Saint-Domingue as the world's largest producer.

Long established in Brazil, sugar-production spread to other parts of South America, as well as to newer European colonies in Africa and in the Pacific, where it became especially important in Fiji.

In Colombia, the planting of sugar started very early on, and entrepreneurs imported many African slaves to cultivate the fields. The industrialization of the Colombian industry started in 1901 with the establishment of the first steam-powered sugar mill by Santiago Eder.

While no longer grown by slaves, sugar from developing countries has an on-going association with workers earning minimal wages and living in extreme poverty.

The rise of beet sugar

In 1747 the German chemist Andreas Marggraf identified sucrose in beet-root. This discovery remained a mere curiosity for some time, but eventually Marggraf's student Franz Achard built a sugarbeet-processing factory at Cunern in Silesia (in present-day Poland), under the patronage of King Frederick William III of Prussia (reigned 1797 - 1840). While never profitable, this plant operated from 1801 until it suffered destruction during the Napoleonic Wars (ca 1802 - 1815).

Napoleon, cut off from Caribbean imports by a British blockade, and at any rate not wanting to fund British merchants, banned imports of sugar in 1813. The beet-sugar industry that emerged in consequence grew, and today sugar-beet provides approximately 30% of world sugar production.

In the developed countries, the sugar industry relies on machinery, with a low requirement for manpower. A large beet-refinery producing around 1,500 tonnes of sugar a day needs a permanent workforce of about 150 for 24-hour production.

Mechanization

Beginning in the late 18th century, the production of sugar became increasingly mechanized. The steam engine first powered a sugar-mill in Jamaica in 1768, and soon after, steam replaced direct firing as the source of process heat.

In 1813 the British chemist Edward Charles Howard invented a method of refining sugar that involved boiling the cane juice not in an open kettle, but in a closed vessel heated by steam and held under partial vacuum. At reduced pressure, water boils at a lower temperature, and this development both saved fuel and reduced the amount of sugar lost through caramelization. Further gains in fuel-efficiency came from the multiple-effect evaporator, designed by the African-American engineer Norbert Rillieux (perhaps as early as the 1820s, although the first working model dates from 1845). This system consisted of a series of vacuum pans, each held at a lower pressure than the previous one. The vapors from each pan served to heat the next, with minimal heat wasted. Today, many industries use multiple-effect evaporators for evaporating water.

The process of separating sugar from molasses also received mechanical attention: David Weston first applied the centrifuge to this task in Hawaii in 1852.

Etymology

In the case of sugar, the etymology reflects the spread of the commodity. The English word "sugar" originates from the Arabic and Persian word shakar,[5] itself derived from Sanskrit Sharkara.[4] It came to English by way of French, Spanish and/or Italian, which derived their word for sugar from the Arabic and Persian shakar (whence the Portuguese word açúcar, the Spanish word azúcar, the Italian word zucchero, the Old French word zuchre and the contemporary French word sucre). (Compare the OED.) The Greek word for "sugar", zahari, means "sugar" or "pebble". Note that the English word jaggery (meaning "coarse brown Indian sugar") has similar ultimate etymological origins (presumably in Sanskrit).

As a food

Originally a luxury, sugar eventually became sufficiently cheap and common to influence standard cuisine. Britain and the Caribbean islands have cuisines where the use of sugar became particularly prominent.

Sugar forms a major element in confectionery and in desserts. Cooks use it as a food preservative as well as for sweetening.

Human health

Some commentators[attribution needed] have suggested links between sugar-consumption and health hazards, including obesity and tooth-decay.

Tooth-decay

Tooth-decay has arguably become the most prominent health-hazard associated with the consumption of sugar. Oral bacteria such as Streptococcus mutans live in dental plaque and metabolize sugars into lactic acid. High concentrations of acid may result on the surface of a tooth, leading to tooth demineralization.[6][7]

The American Dental Association sees[citation needed] tooth decay as caused "mostly" by starchy foods like breadsticks, cereals and potato-chips that linger on teeth and prolong acid-production, not by simple sugars that dissolve rapidly in the mouth.

Diabetes

Diabetes, a disease that causes the body to metabolize sugar poorly, occurs when either:

  1. the body's cells ignore insulin, a chemical that allows the metabolizing of sugar (Type 2 diabetes)
  2. the body attacks the cells producing the insulin (Type 1 diabetes)

When glucose builds up in the bloodstream, it can cause two problems:

  1. in the short term, cells become starved for energy because they do not have access to the glucose
  2. in the long term, frequent glucose build-up can damage many of the body's organs, including the eyes, kidneys, nerves and/or heart

Authorities advise diabetics to avoid sugar-rich foods to prevent adverse reactions.[8]

Obesity

In the United States of America, a scientific/health debate has started[citation needed] over the causes of a steep rise in obesity in the general population — and one view posits increased consumption of carbohydrates in recent decades as a major factor.[9]

Obesity can result from a number of factors including:

  • an increased intake of energy-dense foods — high in fat and sugars but low in vitamins, minerals and other micronutrients (see United Nations advice below); and
  • decreased physical activity.[10]

    The National Health and Nutrition Examination Survey I and Continuous indicates that the population in the United States has increased its proportion of energy-consumption from carbohydrates and decreased its proportion from total fat while obesity has increased. This implies, along with the United Nations report cited below, that obesity may correlate better with sugar-consumption than with fat-consumption, and that reducing fat-consumption while increasing sugar-consumption actually increases the level of obesity. The following table summarizes this study (based on the proportion of energy-intake from different food sources for US Adults 20-74 years old, as carried out by the U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Health Statistics, Hyattsville, MD[11]):

    Year Male/Female Carbohydrate Fat Protein Obesity
    1971 Male 42.4% 36.9% 16.5% 12.1%
    1971 Female 45.4% 36.1% 16.9% 16.6%
    2000 Male 49.0% 32.8% 15.5% 27.7%
    2000 Female 51.6% 32.8% 15.1% 34.0%

    Another study[citation needed] published in 2002 and conducted by the National Academy of Sciences over a 3-year period concluded: “There is no clear and consistent association between increased intakes of added sugars and BMI.” (BMI or "body-mass Index" measures body-weight and height.)

    Gout

    Researchers have implicated sugary drinks high in fructose in a surge in cases of the painful joint-disease gout.[12]

    United Nations nutritional advice

    In 2003, four United Nations agencies, (including the World Health Organization (WHO) and the Food and Agriculture Organization (FAO)) commissioned a report compiled by a panel of 30 international experts. The panel stated that the total of free sugars (all monosaccharides and disaccharides added to foods by manufacturers, cooks or consumers, plus sugars naturally present in honey, syrups and fruit juices) should not account for more than 10% of the energy intake of a healthy diet, while carbohydrates in total should represent between 55% and 75% of the energy-intake.[13]

    Debate on extrinsic sugar

    Argument continues as to the value of extrinsic sugar (sugar added to food) compared to that of intrinsic sugar (naturally present in food). Adding sugar to food particularly enhances taste, but does increase the total number of calories, among other negative effects on health and physiology.

    In the United States of America, sugar has become increasingly evident in food products, as more food-manufacturers add sugar or high-fructose corn-syrup to a wide variety of consumables. Candy-bars, soft drinks, chips, snacks, fruit-juice, peanut-butter, soups, ice-cream, jams, jellies, yogurt, and many breads have added sugars. Five Alive, for example, portrayed by its suppliers as "all natural" and featuring pictures of five different types of fruit on its label, comprises only 41% fruit juice, having high-fructose corn-syrup as its prime ingredient.

    Many doctors argue that health authorities should classify sugar and high-fructose corn-syrup as food additives.[14] A few MDs go so far as to call refined sugar a poison.[15]

    The anthropologist and dentist Weston A. Price, writing in 1939,[16] correlated the use of refined sugar (and refined grains) with malnutrition in pregnant women, malformation of the palate and jaw in their children, followed by cramping of teeth in adolescence (leading to crooked teeth and the removal of wisdom teeth molars). Price correlated other ailments and the impaired function of the pituitary or master gland with consumption of refined sugar, as well as rates of infant mortality, subnormal intelligence, delinquency, and incarceration. He also correlated the underdevelopment of the pelvis, which in women would lead to complications (pain, death, etc.) in childbirth.

    Virtually all of these symptoms became the norm in modern populations consuming typical amounts of refined sugar and other "modern foods of commerce".[citation needed] Besides the rotting of teeth, interruptible or resumable merely by removing or re-introducing white sugar into a diet,[citation needed] the correlations with consumption of refined sugar may relate less to the consumption of refined sugar itself than to the absence of the consumption of "nourishment",[original research?] a category in which Price did not include refined sugar.

    A United Nations study[17] directly creates a definition that includes all extrinsic sugars and separates them completely from intrinsic sugars, labeling them directly as a cause of obesity and of other preventable chronic diseases.

    Concerns of vegetarians and vegans

    The sugar-refining industry often uses bone-char (calcinated animal bones) for decolorizing.[18] This concerns vegans and vegetarians; about a quarter of the sugar in the U.S. gets processed using bone-char as a filter and the rest gets processed with activated carbon. As bone-char does not get into the sugar, the relevant authorities consider sugar processed this way as parve/kosher.

    Vegetarians and vegans may also object to the impact that the burning of the cane-fields (a common part of the harvesting practice) has on insects, rats, snakes, and other life residing in the fields.[19]

    Production

    Image:Cut sugarcane.jpg
    Harvested sugarcane from India ready for processing.

    Table sugar (sucrose) comes from plant sources. Two important sugar crops predominate: sugarcane (Saccharum spp.) and sugar beets (Beta vulgaris), in which sugar can account for 12% to 20% of the plant's dry weight. Some minor commercial sugar crops include the date palm (Phoenix dactylifera), sorghum (Sorghum vulgare), and the sugar maple (Acer saccharum). In the financial year 2001/2002, worldwide production of sugar amounted to 134.1 million tonnes.

    The first production of sugar from sugar-cane took place in India. Alexander the Great's companions reported seeing "honey produced without the intervention of bees" and it remained exotic in Europe until the Arabs started cultivating it in Sicily and Spain. Only after the Crusades did it begin to rival honey as a sweetener in Europe. The Spanish began cultivating sugar-cane in the West Indies in 1506 (and in Cuba in 1523). The Portuguese first cultivated sugar-cane in Brazil in 1532.

    Most cane-sugar comes from countries with warm climates, such as Brazil, India, China, Thailand, Mexico and Australia, the top sugar-producing countries in the world.[20] Brazil overshadows most countries, with roughly 30 million tonnes of cane-sugar produced in 2006, while India produced 21 million, China 11 million, and Thailand and Mexico roughly 5 million each. Viewed by region, Asia predominates in cane-sugar production, with large contributions from China, India and Thailand and other countries combining to account for 40% of global production in 2006. South America comes in second place with 32% of global production; Africa and Central America each produce 8% and Australia 5%. The United States, the Caribbean and Europe make up the remainder, with roughly 3% each.[21]

    Beet-sugar comes from regions with cooler climates: northwest and eastern Europe, northern Japan, plus some areas in the United States (including California). In the northern hemisphere, the beet-growing season ends with the start of harvesting around September. Harvesting and processing continues until March in some cases. The availability of processing-plant capacity, and the weather both influence the duration of harvesting and processing - the industry can lay up harvested beet until processed, but frost-damaged beet becomes effectively unprocessable.

    The European Union (EU) has become the world's second-largest sugar exporter. The Common Agricultural Policy of the EU sets maximum quotas for members' production to match supply and demand, and a price. Europe exports excess production quota (approximately 5 million tonnes in 2003). Part of this, "quota" sugar, gets subsidised from industry levies, the remainder (approximately half) sells as "C quota" sugar at market prices without subsidy. These subsidies and a high import tariff make it difficult for other countries to export to the EU states, or to compete with the Europeans on world markets.

    The United States sets high sugar prices to support its producers, with the effect that many former consumers of sugar have switched to corn syrup (beverage-manufacturers) or moved out of the country (candy-makers).

    The cheap prices of glucose syrups produced from wheat and corn (maize) threaten the traditional sugar market. Used in combination with artificial sweeteners, they can allow drink-manufacturers to produce very low-cost goods.

    Cane

    Main article: Sugarcane

    Since the 6th century BC cane-sugar producers have crushed the harvested vegetable material from sugar-cane in order to collect and filter the juice. They then treat the liquid (often with lime (calcium oxide)) to remove impurities and then neutralize it. Boiling the juice then allows the sediment to settle to the bottom for dredging out, while the scum rises to the surface for skimming off. In cooling, the liquid crystallizes, usually in the process of stirring, to produce sugar crystals. Centrifuges usually remove the uncrystallized syrup. The producers can then either sell the resultant sugar, as is, for use; or process it further to produce lighter grades. This processing may take place in another factory in another country. Sugar cane is the fourth in the list for agriculture in china.

    Beet

    Sugar beets
    Sugar beets
    Main article: Sugar beet

    Beet-sugar producers slice the washed beets, then extract the sugar with hot water in a "diffuser". An alkaline solution ("milk of lime" and carbon dioxide from the lime kiln) then serves to precipitate impurities (see carbonatation). After filtration, evaporation concentrates the juice to a content of about 70% solids, and controlled crystallisation extracts the sugar. A centrifuge removes the sugar crystals from the liquid, which gets recycled in the crystalliser stages. When economic constraints prevent the removal of more sugar, the manufacturer discards the remaining liquid, now known as molasses.

    Sieving the resultant white sugar produces different grades for selling.

    Cane versus beet

    Little perceptible difference exists between sugar produced from beet and that from cane. Chemical tests can distinguish the two, and some tests aim to detect fraudulent abuse of European Union subsidies or to aid in the detection of adulterated fruit-juice.

    The production of sugar-cane needs approximately four times as much water as the production of sugar-beet, therefore some countries that traditionally produced cane-sugar (such as Egypt) have seen the building of new beet-sugar factories recently. On the other hand, sugar cane tolerates hot climates better. Some sugar-factories process both sugar cane and sugar beets and extend their processing period in that way.

    The production of sugar results in residues which differ substantially depending on the raw materials used and on the place of production. While cooks often use cane molasses in food-preparation, humans find molasses from sugar-beet unpalatable, and it therefore ends up mostly as industrial fermentation feedstock (for example in alcohol distilleries), or as animal-feed. Once dried, either type of molasses can serve as fuel for burning.

    Culinary sugars

    Image:Raw sugar closeup.jpg
    Grainier, raw sugar.

    So-called raw sugars comprise yellow to brown sugars made by clarifying the source syrup by boiling and drying with heat, until it becomes a crystalline solid, with minimal chemical processing.[citation needed] Raw beet sugars result from the processing of sugar-beet juice, but only as intermediates en route to white sugar. Types of raw sugar include demerara, muscovado, and turbinado. Mauritius and Malawi export significant quantities of such specialty sugars. Manufacturers sometimes prepare raw sugar as loaves rather than as a crystalline powder, by pouring sugar and molasses together into molds and allowing the mixture to dry. This results in sugar-cakes or loaves, called jaggery or gur in India, pingbian tang in China, and panela, panocha, pile, piloncillo and pão-de-açúcar in various parts of Latin America. In South America, truly raw sugar, unheated and made from sugar-cane grown on farms, does not have a large market-share.

    Mill white sugar, also called plantation white, crystal sugar, or superior sugar, consists of raw sugar where the production process does not remove colored impurities, but rather bleaches them white by exposure to sulfur dioxide. Though the most common form of sugar in sugarcane-growing areas, this product does not store or ship well; after a few weeks, its impurities tend to promote discoloration and clumping.

    Blanco directo, a white sugar common in India and other south Asian countries, comes from precipitating many impurities out of the cane juice by using phosphatation — a treatment with phosphoric acid and calcium hydroxide similar to the carbonatation technique used in beet-sugar refining. In terms of sucrose purity, blanco directo is more pure than mill white, but less pure than white refined sugar.

    White refined sugar has become the most common form of sugar in North America as well as in Europe. Refined sugar can be made by dissolving raw sugar and purifying it with a phosphoric acid method similar to that used for blanco directo, a carbonatation process involving calcium hydroxide and carbon dioxide, or by various filtration strategies. It is then further purified by filtration through a bed of activated carbon or bone char depending on where the processing takes place. Beet sugar refineries produce refined white sugar directly without an intermediate raw stage. White refined sugar is typically sold as granulated sugar, which has been dried to prevent clumping.

    Granulated sugar comes in various crystal sizes — for home and industrial use — depending on the application:

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