Sucrose, a
disaccharide, is a
sugar composed of
glucose
Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, usi ...
and
fructose
Fructose, or fruit sugar, is a ketonic simple sugar found in many plants, where it is often bonded to glucose to form the disaccharide sucrose. It is one of the three dietary monosaccharides, along with glucose and galactose, that are absorb ...
subunits. It is produced naturally in plants and is the main constituent of
white sugar. It has the
molecular formula .
For human consumption, sucrose is extracted and refined from either
sugarcane or
sugar beet.
Sugar mills – typically located in
tropical regions near where sugarcane is grown – crush the cane and produce raw sugar which is shipped to other factories for refining into pure sucrose. Sugar beet factories are located in
temperate climates where the beet is grown, and process the beets directly into refined sugar. The
sugar-refining process involves washing the raw sugar crystals before dissolving them into a sugar syrup which is filtered and then passed over carbon to remove any residual colour. The sugar syrup is then concentrated by boiling under a vacuum and crystallized as the final purification process to produce crystals of pure sucrose that are clear, odorless, and sweet.
Sugar is often an
added ingredient in food production and recipes. About 185 million
tonne
The tonne ( or ; symbol: t) is a unit of mass equal to 1000 kilograms. It is a non-SI unit accepted for use with SI. It is also referred to as a metric ton to distinguish it from the non-metric units of the short ton ( United State ...
s of sugar were produced worldwide in 2017.
Sucrose is particularly dangerous as a risk factor for
tooth decay because ''
Streptococcus mutans'' bacteria convert it into a sticky, extracellular,
dextran-based
polysaccharide that allows them to cohere, forming plaque. Sucrose is the only sugar that bacteria can use to form this sticky polysaccharide.
Etymology
The word ''sucrose'' was coined in 1857, by the English chemist
William Miller from the
French
French (french: français(e), link=no) may refer to:
* Something of, from, or related to France
** French language, which originated in France, and its various dialects and accents
** French people, a nation and ethnic group identified with Franc ...
("sugar") and the generic chemical suffix for sugars ''
-ose
The suffix -ose ( or ) is used in biochemistry to form the names of sugars. This Latin suffix means "full of", "abounding in", "given to", or "like". Numerous systems exist to name specific sugars more descriptively.
Monosaccharides, the simplest ...
''. The abbreviated term ''Suc'' is often used for ''sucrose'' in scientific literature.
The name ''saccharose'' was coined in 1860 by the French chemist
Marcellin Berthelot. Saccharose is an obsolete name for sugars in general, especially sucrose.
Physical and chemical properties
Structural O-α-D-glucopyranosyl-(1→2)-β-D-fructofuranoside
In sucrose, the
monomers glucose and fructose are linked via an ether bond between C1 on the
glucosyl subunit and C2 on the
fructosyl unit. The bond is called a
glycosidic linkage. Glucose exists predominantly as a mixture of α and β "pyranose"
anomer
In carbohydrate chemistry, a pair of anomers () is a pair of near-identical stereoisomers that differ at only the anomeric carbon, the carbon that bears the aldehyde or ketone functional group in the sugar's open-chain form. However, in order f ...
s, but sucrose has only the α form. Fructose exists as a mixture of five
tautomer
Tautomers () are structural isomers (constitutional isomers) of chemical compounds that readily interconvert.
The chemical reaction interconverting the two is called tautomerization. This conversion commonly results from the relocation of a hyd ...
s but sucrose has only the β-
D-fructofuranose form. Unlike most
disaccharides, the glycosidic bond in sucrose is formed between the reducing ends of both glucose and fructose, and not between the reducing end of one and the non-reducing end of the other. This linkage inhibits further bonding to other saccharide units, and prevents sucrose from spontaneously reacting with cellular and circulatory macromolecules in the manner that glucose and other reducing sugars do. Since sucrose contains no anomeric hydroxyl groups, it is classified as a non-
reducing sugar.
Sucrose crystallizes in the
monoclinic space group P2
1 with room-temperature lattice parameters ''a'' = 1.08631 nm, ''b'' = 0.87044 nm, ''c'' = 0.77624 nm, β = 102.938°.
The purity of sucrose is measured by
polarimetry, through the rotation of
plane-polarized light by a sugar solution. The
specific rotation at using yellow "sodium-D" light (589 nm) is +66.47°. Commercial samples of sugar are assayed using this parameter. Sucrose does not deteriorate at ambient conditions.
Thermal and oxidative degradation
Sucrose does not melt at high temperatures. Instead, it decomposes at to form
caramel. Like other
carbohydrate
In organic chemistry, a carbohydrate () is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula (where ''m'' may or ...
s, it combusts to
carbon dioxide
Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is t ...
and water. Mixing sucrose with the oxidizer
potassium nitrate produces the fuel known as
rocket candy that is used to propel amateur rocket motors.
This reaction is somewhat simplified though. Some of the carbon does get fully oxidized to carbon dioxide, and other reactions, such as the
water-gas shift reaction also take place. A more accurate theoretical equation is:
Sucrose burns with
chloric acid, formed by the reaction of
hydrochloric acid
Hydrochloric acid, also known as muriatic acid, is an aqueous solution of hydrogen chloride. It is a colorless solution with a distinctive pungent smell. It is classified as a strong acid. It is a component of the gastric acid in the dig ...
and
potassium chlorate:
Sucrose can be dehydrated with
sulfuric acid to form a black,
carbon
Carbon () is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—its atom making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes ...
-rich solid, as indicated in the following idealized equation:
The formula for sucrose's decomposition can be represented as a two-step reaction: the first simplified reaction is dehydration of sucrose to pure carbon and water, and then carbon oxidises to with from air.
Hydrolysis
Hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile.
Biological hydrolysis ...
breaks the glycosidic bond converting sucrose into
glucose
Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, usi ...
and
fructose
Fructose, or fruit sugar, is a ketonic simple sugar found in many plants, where it is often bonded to glucose to form the disaccharide sucrose. It is one of the three dietary monosaccharides, along with glucose and galactose, that are absorb ...
. Hydrolysis is, however, so slow that solutions of sucrose can sit for years with negligible change. If the
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecule ...
sucrase is added, however, the reaction will proceed rapidly. Hydrolysis can also be accelerated with acids, such as
cream of tartar
Potassium bitartrate, also known as potassium hydrogen tartrate, with formula K C4 H5 O6, is a byproduct of winemaking. In cooking, it is known as cream of tartar. It is processed from the potassium acid salt of tartaric acid (a carboxylic ...
or lemon juice, both weak acids. Likewise, gastric acidity converts sucrose to glucose and fructose during digestion, the bond between them being an acetal bond which can be broken by an acid.
Given
(higher) heats of combustion of 1349.6 kcal/mol for sucrose, 673.0 for glucose, and 675.6 for fructose, hydrolysis releases about per mole of sucrose, or about 3
small calories per gram of product.
Synthesis and biosynthesis of sucrose
The
biosynthesis of sucrose proceeds via the precursors
UDP-glucose and
fructose 6-phosphate, catalyzed by the enzyme
sucrose-6-phosphate synthase. The energy for the reaction is gained by the cleavage of
uridine diphosphate (UDP).
Sucrose is formed by plants,
algae
Algae ( , ; : alga ) are any of a large and diverse group of photosynthetic, eukaryotic organisms. The name is an informal term for a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from ...
and
cyanobacteria but not by other
organism
In biology, an organism () is any life, living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy (biology), taxonomy into groups such as Multicellular o ...
s. Sucrose is the end product of
photosynthesis and is found naturally in many food plants along with the
monosaccharide fructose. In many fruits, such as
pineapple and
apricot, sucrose is the main sugar. In others, such as
grapes and
pears, fructose is the main sugar.
Chemical synthesis
After numerous unsuccessful attempts by others,
Raymond Lemieux and George Huber succeeded in synthesizing sucrose from
acetylated glucose and fructose in 1953.
Sources
In nature, sucrose is present in many plants, and in particular their roots, fruits and
nectars, because it serves as a way to store energy, primarily from
photosynthesis. Many mammals, birds, insects and bacteria accumulate and feed on the sucrose in plants and for some it is their main food source. Although
honeybees consume sucrose, the
honey
Honey is a sweet and viscous substance made by several bees, the best-known of which are honey bees. Honey is made and stored to nourish bee colonies. Bees produce honey by gathering and then refining the sugary secretions of plants (primar ...
they produce consists primarily of fructose and glucose, with only trace amounts of sucrose.
As fruits ripen, their sucrose content usually rises sharply, but some fruits contain almost no sucrose at all. This includes grapes, cherries, blueberries, blackberries, figs, pomegranates, tomatoes, avocados, lemons and limes.
Sucrose is a naturally occurring sugar, but with the advent of
industrialization, it has been increasingly refined and consumed in all kinds of processed foods.
Production
History of sucrose refinement

The production of table sugar has a long history. Some scholars claim Indians discovered how to crystallize sugar during the
Gupta dynasty
The Gupta Empire was an Outline of ancient India, ancient Indian empire which existed from the early 4th century CE to late 6th century CE. At its zenith, from approximately 319 to 467 CE, it covered much of the Indian subcontinent. This period ...
, around AD 350.
[
Adas, Michael (2001)]
''Agricultural and Pastoral Societies in Ancient and Classical History''
. Temple University Press. . p. 311.
Other scholars point to the ancient manuscripts of China, dated to the 8th century BC, where one of the earliest historical mentions of
sugar cane is included along with the fact that their knowledge of sugar cane was derived from India.
By about 500 BC, residents of modern-day India began making sugar syrup, cooling it in large flat bowls to produce raw sugar crystals that were easier to store and transport. In the local Indian language, these crystals were called (), which is the source of the word ''candy''.
The army of
Alexander the Great
Alexander III of Macedon ( grc, Ἀλέξανδρος, Alexandros; 20/21 July 356 BC – 10/11 June 323 BC), commonly known as Alexander the Great, was a king of the ancient Greek kingdom of Macedon. He succeeded his father Philip II to ...
was halted on the banks of river
Indus 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 (), pronounced as () in Greek (Modern Greek, , ). On their return journey, the Greek soldiers carried back some of the "honey-bearing reeds". Sugarcane remained a limited crop for over a millennium. Sugar was a rare commodity and traders of sugar became wealthy. Venice, at the height of its financial power, was the chief sugar-distributing center of Europe.
Arabs started producing it in
Sicily
(man) it, Siciliana (woman)
, population_note =
, population_blank1_title =
, population_blank1 =
, demographics_type1 = Ethnicity
, demographics1_footnotes =
, demographi ...
and
Spain
, image_flag = Bandera de España.svg
, image_coat = Escudo de España (mazonado).svg
, national_motto = '' Plus ultra'' ( Latin)(English: "Further Beyond")
, national_anthem = (English: "Royal March")
, ...
. Only after the
Crusades
The Crusades were a series of religious wars initiated, supported, and sometimes directed by the Latin Church in the medieval period. The best known of these Crusades are those to the Holy Land in the period between 1095 and 1291 that were ...
did it begin to rival honey as a sweetener in Europe. The Spanish began cultivating sugarcane in the
West Indies
The West Indies is a subregion of North America, surrounded by the North Atlantic Ocean and the Caribbean Sea that includes 13 independent island countries and 18 dependencies and other territories in three major archipelagos: the Great ...
in 1506 (
Cuba
Cuba ( , ), officially the Republic of Cuba ( es, República de Cuba, links=no ), is an island country comprising the island of Cuba, as well as Isla de la Juventud and several minor archipelagos. Cuba is located where the northern Caribbea ...
in 1523). The
Portuguese first cultivated sugarcane in
Brazil
Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...
in 1532.
Sugar remained a luxury in much of the world until the 18th century. Only the wealthy could afford it. In the 18th century, the demand for table sugar boomed in Europe and by the 19th century it had become regarded as a human necessity.
[ The use of sugar grew from use in tea, to cakes, confectionery and ]chocolate
Chocolate is a food made from roasted and ground cacao seed kernels that is available as a liquid, solid, or paste, either on its own or as a flavoring agent in other foods. Cacao has been consumed in some form since at least the Olmec civil ...
s. Suppliers marketed sugar in novel forms, such as solid cones, which required consumers to use a sugar nip, a pliers-like tool, in order to break off pieces.
The demand for cheaper table sugar drove, in part, colonization of tropical islands and nations where labor-intensive sugarcane plantations and table sugar manufacturing could thrive. Growing sugar cane crop in hot humid climates, and producing table sugar in high temperature sugar mills was harsh, inhumane work. The demand for cheap labor for this work, in part, first drove slave trade from Africa (in particular West Africa), followed by indentured labor trade from South Asia (in particular India). Millions of slaves, followed by millions of indentured laborers were brought into the Caribbean, Indian Ocean, Pacific Islands, East Africa, Natal, north and eastern parts of South America, and southeast Asia. The modern ethnic mix of many nations, settled in the last two centuries, has been influenced by table sugar.
Beginning in the late 18th century, the production of sugar became increasingly mechanized. The steam engine
A steam engine is a heat engine that performs mechanical work using steam as its working fluid. The steam engine uses the force produced by steam pressure to push a piston back and forth inside a cylinder. This pushing force can be ...
first powered a sugar mill in Jamaica
Jamaica (; ) is an island country situated in the Caribbean Sea. Spanning in area, it is the third-largest island of the Greater Antilles and the Caribbean (after Cuba and Hispaniola). Jamaica lies about south of Cuba, and west of Hispan ...
in 1768, and, soon after, steam replaced direct firing as the source of process heat. During the same century, Europeans began experimenting with sugar production from other crops. Andreas Marggraf
Andreas Sigismund Marggraf (; 3 March 1709 – 7 August 1782) was a German chemist from Berlin, then capital of the Margraviate of Brandenburg, and a pioneer of analytical chemistry. He isolated zinc in 1746 by heating calamine and carbon. Though h ...
identified sucrose in beet root and his student Franz Achard
Franz Karl Achard (28 April 1753 – 20 April 1821) was a German (Prussian) chemist, geoscientist, physicist, and biologist. His principal discovery was the production of sugar from sugar beets.
Life and work
Achard was born in Berlin, the ...
built a sugar beet processing factory in Silesia (Prussia). The beet-sugar industry took off during the Napoleonic Wars
The Napoleonic Wars (1803–1815) were a series of major global conflicts pitting the French Empire and its allies, led by Napoleon I, against a fluctuating array of European states formed into various coalitions. It produced a period of Fren ...
, when France and the continent were cut off from Caribbean sugar. In 2009, about 20 percent of the world's sugar was produced from beets.
Today, a large beet refinery producing around 1,500 tonnes of sugar a day needs a permanent workforce of about 150 for 24-hour production.
Trends
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. Minor commercial sugar crops include the date palm (''Phoenix dactylifera''), sorghum
''Sorghum'' () is a genus of about 25 species of flowering plants in the grass family ( Poaceae). Some of these species are grown as cereals for human consumption and some in pastures for animals. One species is grown for grain, while many ot ...
(''Sorghum vulgare''), and the sugar maple (''Acer saccharum''). Sucrose is obtained by extraction of these crops with hot water; concentration of the extract gives syrups, from which solid sucrose can be crystallized. In 2017, worldwide production of table sugar amounted to 185 million tonnes.[
Most cane sugar comes from countries with warm climates, because sugarcane does not tolerate frost. Sugar beets, on the other hand, grow only in cooler temperate regions and do not tolerate extreme heat. About 80 percent of sucrose is derived from sugarcane, the rest almost all from sugar beets.
In mid-2018, India and Brazil had about the same production of sugar – 34 million tonnes – followed by the ]European Union
The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been ...
, Thailand
Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is b ...
, and China as the major producers. India, the European Union, and China were the leading domestic consumers of sugar in 2018.[
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 store harvested beets until processed, but a frost-damaged beet becomes effectively unprocessable.
The United States sets high sugar prices to support its producers, with the effect that many former purchasers of sugar have switched to corn syrup (beverage manufacturers) or moved out of the country (candy manufacturers).
The low prices of glucose syrups produced from ]wheat
Wheat is a grass widely cultivated for its seed, a cereal grain that is a worldwide staple food. The many species of wheat together make up the genus ''Triticum'' ; the most widely grown is common wheat (''T. aestivum''). The archaeolog ...
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.
High-fructose corn syrup
High-fructose corn syrup (HFCS) is significantly cheaper as a sweetener for food and beverage manufacturing than refined sucrose. This has led to sucrose being partially displaced in U.S. industrial food production by HFCS and other non-sucrose natural sweeteners.[
Reports in public media have regarded HFCS as less safe than sucrose.] However, the most common forms of HFCS contain either 42 percent fructose, mainly used in processed foods, or 55 percent fructose, mainly used in soft drinks, as compared to sucrose, which is 50 percent fructose. Given approximately equal glucose and fructose content, there does not appear to be a significant difference in safety. That said, clinical dietitians, medical professionals, and the U.S. Food and Drug Administration
The United States Food and Drug Administration (FDA or US FDA) is a federal agency of the Department of Health and Human Services. The FDA is responsible for protecting and promoting public health through the control and supervision of food ...
(FDA) agree that dietary sugars are a source of empty calories associated with certain health problems, and recommend limiting the overall consumption of sugar-based sweeteners.[
]
Types
Cane
Since the 6th century BC, cane sugar producers have crushed the harvested vegetable material from sugarcane 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 sugar product for use as is, or process it further to produce lighter grades. The later processing may take place in another factory in another country.
Sugarcane is a major component of Brazilian agriculture; the country is the world's largest producer of sugarcane and its derivative products, such as crystallized sugar and ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a h ...
( ethanol fuel).
Beet
Beet sugar producers slice the washed beets, then extract the sugar with hot water in a " diffuser". An alkaline solution ("milk of lime
Limewater is the common name for a saturated aqueous solution of calcium hydroxide. Calcium hydroxide, Ca(OH)2, is sparsely soluble at room temperature in water (1.5 g/L at 25 °C). "Pure" (i.e. less than or fully saturated) limewater i ...
" and carbon dioxide
Carbon dioxide ( chemical formula ) is a chemical compound made up of molecules that each have one carbon atom covalently double bonded to two oxygen atoms. It is found in the gas state at room temperature. In the air, carbon dioxide is t ...
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, or sells it on to producers of animal feed.
Sieving the resultant white sugar produces different grades for selling.
=Cane versus beet
=
It is difficult to distinguish between fully refined sugar produced from beet and cane. One way is by isotope analysis of carbon. Cane uses C4 carbon fixation, and beet uses C3 carbon fixation, resulting in a different ratio of 13C and 12C isotopes in the sucrose. Tests are used to detect fraudulent abuse of European Union
The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been ...
subsidies or to aid in the detection of adulterated fruit juice.
Sugar cane tolerates hot climates better, but the production of sugar cane needs approximately four times as much water as the production of sugar beet. As a result, some countries that traditionally produced cane sugar (such as Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Med ...
) have built new beet sugar factories since about 2008. Some sugar factories process both sugar cane and sugar beets and extend their processing period in that way.
The production of sugar leaves residues that differ substantially depending on the raw materials used and on the place of production. While cane molasses is often used in food preparation, humans find molasses from sugar beets unpalatable, and it consequently 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.
Pure beet sugar is difficult to find, so labelled, in the marketplace. Although some makers label their product clearly as "pure cane sugar", beet sugar is almost always labeled simply as sugar or pure sugar. Interviews with the 5 major beet sugar-producing companies revealed that many store brands or "private label" sugar products are pure beet sugar. The lot code can be used to identify the company and the plant from which the sugar came, enabling beet sugar to be identified if the codes are known.
Culinary sugars
=Mill white
=
Mill white, also called plantation white, crystal sugar or superior sugar is produced from raw sugar. It is exposed to sulfur dioxide
Sulfur dioxide ( IUPAC-recommended spelling) or sulphur dioxide (traditional Commonwealth English) is the chemical compound with the formula . It is a toxic gas responsible for the odor of burnt matches. It is released naturally by volcanic ...
during the production to reduce the concentration of color compounds and helps prevent further color development during the crystallization process. Although common to sugarcane-growing areas, this product does not store or ship well. After a few weeks, its impurities tend to promote discoloration and clumping; therefore this type of sugar is generally limited to local consumption.
=Blanco directo
=
Blanco directo, a white sugar common in India and other south Asian countries, is produced by precipitating many impurities out of cane juice using phosphoric acid
Phosphoric acid (orthophosphoric acid, monophosphoric acid or phosphoric(V) acid) is a colorless, odorless phosphorus-containing solid, and inorganic compound with the chemical formula . It is commonly encountered as an 85% aqueous solutio ...
and calcium hydroxide, similar to the carbonatation technique used in beet sugar refining. Blanco directo is more pure than mill white sugar, but less pure than white refined.
=White refined
=
White refined is the most common form of sugar in North America and Europe. Refined sugar is made by dissolving and purifying raw sugar using phosphoric acid
Phosphoric acid (orthophosphoric acid, monophosphoric acid or phosphoric(V) acid) is a colorless, odorless phosphorus-containing solid, and inorganic compound with the chemical formula . It is commonly encountered as an 85% aqueous solutio ...
similar to the method 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
Activated carbon, also called activated charcoal, is a form of carbon commonly used to filter contaminants from water and air, among many other uses. It is processed (activated) to have small, low-volume pores that increase the surface area avail ...
or bone char. 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 and comes in various crystal sizes for home and industrial use:
* Coarse-grain, such as ''sanding sugar'' (also called "pearl sugar", "decorating sugar", ''nibbed sugar'' or ''sugar nibs'') is a coarse grain sugar used to add sparkle and flavor atop baked goods and candies. Its large reflective crystals will not dissolve when subjected to heat.
* Granulated, familiar as table sugar, with a grain size about 0.5 mm across.[Sugar Crystal Challenge](_blank)
. IEEE "Sugar cubes" are lumps for convenient consumption produced by mixing granulated sugar with sugar syrup.
* Caster (0.35 mm), a very fine sugar in Britain and other Commonwealth countries, so-named because the grains are small enough to fit through a sugar caster
A sugar caster is a small container, with a perforated top, larger than a salt shaker but similar in form. The sugar caster was part of a set of vessels, and a rack to hold them used to contain spices and condiments on the dining table. The set wou ...
which is a small vessel with a perforated top, from which to sprinkle sugar at table.["castor, n.2." OED Online. Oxford University Press, June 2017. Web. 25 July 2017. It says castor is a misspelling that is now the preferred spelling.] Commonly used in baking and mixed drinks, it is sold as "superfine" sugar in the United States. Because of its fineness, it dissolves faster than regular white sugar and is especially useful in meringues and cold liquids. Caster sugar can be prepared at home by grinding granulated sugar for a couple of minutes in a mortar or food processor.
* Powdered, ''10X sugar,'' ''confectioner's sugar'' (0.060 mm), or ''icing sugar'' (0.024 mm), produced by grinding sugar to a fine powder. The manufacturer may add a small amount of anticaking agent to prevent clumping — either corn starch (1% to 3%) or tri-calcium phosphate
The term calcium phosphate refers to a family of materials and minerals containing calcium ions (Ca2+) together with inorganic phosphate anions. Some so-called calcium phosphates contain oxide and hydroxide as well. Calcium phosphates are wh ...
.
Brown sugar comes either from the late stages of cane sugar refining, when sugar forms fine crystals with significant molasses content, or from coating white refined sugar with a cane molasses syrup (blackstrap molasses). Brown sugar's color and taste becomes stronger with increasing molasses content, as do its moisture-retaining properties. Brown sugars also tend to harden if exposed to the atmosphere, although proper handling can reverse this.
Measurement
Dissolved sugar content
Scientists and the sugar industry use degrees Brix (symbol °Bx), introduced by Adolf Brix, as units of measurement of the mass ratio of dissolved substance to water in a liquid. A 25 °Bx sucrose solution has 25 grams of sucrose per 100 grams of liquid; or, to put it another way, 25 grams of sucrose sugar and 75 grams of water exist in the 100 grams of solution.
The Brix degrees are measured using an infrared sensor. This measurement does not equate to Brix degrees from a density or refractive index measurement, because it will specifically measure dissolved sugar concentration instead of all dissolved solids. When using a refractometer, one should report the result as " refractometric dried substance" (RDS). One might speak of a liquid as having 20 °Bx RDS. This refers to a measure of percent by weight of ''total'' dried solids and, although not technically the same as Brix degrees determined through an infrared method, renders an accurate measurement of sucrose content, since sucrose in fact forms the majority of dried solids. The advent of in-line infrared Brix measurement sensors has made measuring the amount of dissolved sugar in products economical using a direct measurement.
Consumption
Refined sugar was a luxury before the 18th century. It became widely popular in the 18th century, then graduated to becoming a necessary food in the 19th century. This evolution of taste and demand for sugar as an essential food ingredient unleashed major economic and social changes. Eventually, table sugar became sufficiently cheap and common enough to influence standard cuisine and flavored drinks.
Sucrose forms a major element in confectionery and desserts. Cooks use it for sweetening. It can also act as a food preservative
Food preservation includes processes that make food more resistant to microorganism growth and slow the oxidation of fats. This slows down the decomposition and rancidification process. Food preservation may also include processes that inhi ...
when used in sufficient concentrations. Sucrose is important to the structure of many foods, including biscuits and cookies, cakes and pies, candy, and ice cream and sorbets. It is a common ingredient in many processed and so-called "junk food
"Junk food" is a term used to describe food that is high in calories from sugar and/or fat, and possibly also sodium, but with little dietary fiber, protein, vitamins, minerals, or other important forms of nutritional value. It is also known ...
s".
Nutritional information
Fully refined sugar is 99.9% sucrose, thus providing only carbohydrate as dietary nutrient
A nutrient is a substance used by an organism to survive, grow, and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi, and protists. Nutrients can be incorporated into cells for metabolic purposes or excr ...
and 390 kilocalories per 100 g serving (USDA
The United States Department of Agriculture (USDA) is the federal executive department responsible for developing and executing federal laws related to farming, forestry, rural economic development, and food. It aims to meet the needs of com ...
data, right table). There are no micronutrients of significance in fully refined sugar (right table).[
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Metabolism of sucrose
In humans and other mammals, sucrose is broken down into its constituent monosaccharides, glucose and fructose, by sucrase or isomaltase glycoside hydrolases, which are located in the membrane
A membrane is a selective barrier; it allows some things to pass through but stops others. Such things may be molecules, ions, or other small particles. Membranes can be generally classified into synthetic membranes and biological membranes. ...
of the microvilli lining the duodenum. The resulting glucose and fructose molecules are then rapidly absorbed into the bloodstream. In bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am ...
and some animals, sucrose is digested by the enzyme invertase
Invertase is an enzyme that catalyzes the hydrolysis (breakdown) of sucrose (table sugar) into fructose and glucose. Alternative names for invertase include , saccharase, glucosucrase, beta-h-fructosidase, beta-fructosidase, invertin, sucrase, ...
. Sucrose is an easily assimilated macronutrient that provides a quick source of energy, provoking a rapid rise in blood glucose upon ingestion. Sucrose, as a pure carbohydrate, has an energy content of 3.94 kilocalories per gram (or 17 kilojoules per gram).
If consumed excessively, sucrose may contribute to the development of metabolic syndrome, including increased risk for type 2 diabetes
Type 2 diabetes, formerly known as adult-onset diabetes, is a form of diabetes mellitus that is characterized by high blood sugar, insulin resistance, and relative lack of insulin. Common symptoms include increased thirst, frequent urinati ...
, weight gain and obesity in adults and children.
Tooth decay
Tooth decay (dental caries) has become a pronounced health hazard associated with the consumption of sugars, especially sucrose. Oral bacteria such as '' Streptococcus mutans'' live in dental plaque and metabolize ''any'' free sugars (not just sucrose, but also glucose, lactose
Lactose is a disaccharide sugar synthesized by galactose and glucose subunits and has the molecular formula C12H22O11. Lactose makes up around 2–8% of milk (by mass). The name comes from ' (gen. '), the Latin word for milk, plus the suffix ...
, fructose, and cooked starches) into lactic acid
Lactic acid is an organic acid. It has a molecular formula . It is white in the solid state and it is miscible with water. When in the dissolved state, it forms a colorless solution. Production includes both artificial synthesis as well as natur ...
. The resultant lactic acid lowers the pH of the tooth's surface, stripping it of minerals in the process known as tooth decay.
All 6-carbon sugars and disaccharides based on 6-carbon sugars can be converted by dental plaque bacteria into acid that demineralizes teeth, but sucrose may be uniquely useful to '' Streptococcus sanguinis'' (formerly ''Streptococcus sanguis'') and ''Streptococcus mutans''. Sucrose is the only dietary sugar that can be converted to sticky glucans (dextran-like polysaccharides) by extracellular enzymes. These glucans allow the bacteria to adhere to the tooth surface and to build up thick layers of plaque. The anaerobic conditions deep in the plaque encourage the formation of acids, which leads to carious lesions. Thus, sucrose could enable ''S. mutans'', ''S. sanguinis'' and many other species of bacteria to adhere strongly and resist natural removal, e.g. by flow of saliva, although they are easily removed by brushing. The glucans and levans (fructose polysaccharides) produced by the plaque bacteria also act as a reserve food supply for the bacteria.
Such a special role of sucrose in the formation of tooth decay is much more significant in light of the almost universal use of sucrose as the most desirable sweetening agent. Widespread replacement of sucrose by high-fructose corn syrup (HFCS) has not diminished the danger from sucrose. If smaller amounts of sucrose are present in the diet, they will still be sufficient for the development of thick, anaerobic plaque and plaque bacteria will metabolise other sugars in the diet, such as the glucose and fructose in HFCS.
Glycemic index
Sucrose is a disaccharide made up of 50% glucose and 50% fructose and has a glycemic index of 65. Sucrose is digested rapidly, but has a relatively low glycemic index due to its content of fructose, which has a minimal effect on blood glucose.
As with other sugars, sucrose is digested into its components via the enzyme sucrase to glucose (blood sugar). The glucose component is transported into the blood where it serves immediate metabolic demands, or is converted and reserved in the liver
The liver is a major organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it ...
as glycogen
Glycogen is a multibranched polysaccharide of glucose that serves as a form of energy storage in animals, fungi, and bacteria. The polysaccharide structure represents the main storage form of glucose in the body.
Glycogen functions as one o ...
.[
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Gout
The occurrence of gout is connected with an excess production of uric acid. A diet rich in sucrose may lead to gout as it raises the level of insulin, which prevents excretion of uric acid from the body. As the concentration of uric acid in the body increases, so does the concentration of uric acid in the joint liquid and beyond a critical concentration, the uric acid begins to precipitate into crystals. Researchers have implicated sugary drinks high in fructose in a surge in cases of gout.
Sucrose intolerance
UN dietary recommendation
In 2015, the World Health Organization
The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level o ...
published a new guideline on sugars intake for adults and children, as a result of an extensive review of the available scientific evidence by a multidisciplinary group of experts. The guideline recommends that both adults and children ensure their intake of free sugars (monosaccharides and disaccharides added to foods and beverages by the manufacturer, cook or consumer, and sugars naturally present in honey, syrups, fruit juices and fruit juice concentrates) is less than 10% of total energy intake. A level below 5% of total energy intake brings additional health benefits, especially with regards to dental caries.
Religious concerns
The sugar refining industry often uses bone char ( calcinated animal bones) for decolorizing. About 25% of sugar produced in the U.S. is processed using bone char as a filter, the remainder being processed with activated carbon
Activated carbon, also called activated charcoal, is a form of carbon commonly used to filter contaminants from water and air, among many other uses. It is processed (activated) to have small, low-volume pores that increase the surface area avail ...
. As bone char does not seem to remain in finished sugar, Jewish religious leaders consider sugar filtered through it to be pareve
In ''kashrut'', the dietary laws of Judaism, pareve (from yi, פאַרעוו for "neutral", in Hebrew , and also parve and other variant English spellings) is a classification of edible substances that contain neither dairy nor meat ingredients. ...
, meaning that it is neither meat nor dairy and may be used with either type of food. However, the bone char must source to a kosher animal (e.g. cow, sheep) for the sugar to be kosher.
Trade and economics
One of the most widely traded commodities in the world throughout history, sugar accounts for around 2% of the global dry cargo market. International sugar prices show great volatility, ranging from around 3 cents to over 60 cents per pound in the 50 years. About 100 of the world's 180 countries produce sugar from beet or cane, a few more refine raw sugar to produce white sugar, and all countries consume sugar. Consumption of sugar ranges from around 3 kilograms (7 lb) per person per annum in Ethiopia to around 40 kg (90 lb) in Belgium. Consumption per capita rises with income per capita until it reaches a plateau of around 35 kg (75 lb) per person per year in middle income countries.
Many countries subsidize sugar production heavily. The European Union, the United States, Japan, and many developing countries
A developing country is a sovereign state with a lesser developed Industrial sector, industrial base and a lower Human Development Index (HDI) relative to other countries. However, this definition is not universally agreed upon. There is al ...
subsidize domestic production and maintain high tariffs on imports. Sugar prices in these countries have often up to triple the prices on the international market; , with world market sugar futures prices strong, such prices were typically double world prices.
Within international trade bodies, especially in the World Trade Organization
The World Trade Organization (WTO) is an intergovernmental organization that regulates and facilitates international trade. With effective cooperation
in the United Nations System, governments use the organization to establish, revise, and ...
(WTO), the " G20" countries led by Brazil have long argued that, because these sugar markets in essence exclude cane sugar imports, the G20 sugar producers receive lower prices than they would under free trade
Free trade is a trade policy that does not restrict imports or exports. It can also be understood as the free market idea applied to international trade. In government, free trade is predominantly advocated by political parties that hold ...
. While both the European Union
The European Union (EU) is a supranational political and economic union of member states that are located primarily in Europe. The union has a total area of and an estimated total population of about 447million. The EU has often been ...
and United States maintain trade agreements whereby certain developing and least developed countries (LDCs) can sell certain quantities of sugar into their markets, free of the usual import tariffs, countries outside these preferred trade régimes have complained that these arrangements violate the " most favoured nation" principle of international trade. This has led to numerous tariffs and levies in the past.
In 2004, the WTO sided with a group of cane sugar exporting nations (led by Brazil and Australia) and ruled illegal the EU sugar-régime and the accompanying ''ACP-EU Sugar Protocol'', that granted a group of African, Caribbean, and Pacific countries receive preferential access to the European sugar market. In response to this and to other rulings of the WTO, and owing to internal pressures against the EU sugar-régime, the European Commission proposed on 22 June 2005 a radical reform of the EU sugar-régime that cut prices by 39% and eliminated all EU sugar exports.
The African, Caribbean, Pacific and LDC sugar exporters reacted with dismay to the EU sugar proposals. On 25 November 2005, the EC agreed to cut EU sugar prices by 36% as from 2009.
In 2007, it seemed that the U.S. Sugar Program The U.S. Sugar program is the federal commodity support program that maintains a minimum price for sugar, authorized by the 2002 farm bill (P.L. 107–171, Sec. 1401–1403) to cover the 2002-2007 crops of sugar beets and sugarcane.
Designed to ...
could become the next target for reform. However, some commentators expected heavy lobbying from the U.S. sugar industry, which donated $2.7 million to U.S. House and Senate incumbents in the 2006 U.S. election, more than any other group of U.S. food-growers. Especially prominent among sugar lobbyists were the Fanjul Brothers, so-called "sugar barons" who made the single individual contributions of soft money
The financing of electoral campaigns in the United States happens at the federal, state, and local levels by contributions from individuals, corporations, political action committees, and sometimes the government. Campaign spending has risen ...
to both the Democratic and Republican parties in the U.S. political system.
Small quantities of sugar, especially specialty grades of sugar, reach the market as ' fair trade' commodities; the fair trade system produces and sells these products with the understanding that a larger-than-usual fraction of the revenue will support small farmers in the developing world. However, whilst the Fairtrade Foundation offers a premium of $60.00 per tonne to small farmers for sugar branded as "Fairtrade", government schemes such as the U.S. Sugar Program and the ACP-EU Sugar Protocol offer premiums of around $400.00 per tonne above world market prices. However, the EU announced on 14 September 2007 that it had offered "to eliminate all duties and quotas on the import of sugar into the EU".
The U.S. Sugar Association
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
subsequently launched a campaign to promote sugar over artificial substitutes. The Association aggressively contradicts many common beliefs regarding negative side-effects of sugar consumption. The campaign aired a high-profile television commercial during the 2007 Primetime Emmy Awards on FOX Television.
References
Further reading
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External links
3D images of sucrose
{{Authority control
Disaccharides
Sugar
Sugar substitutes