A wheel is a rotating component (typically circular in shape) that is intended to turn on an axlebearing. The wheel is one of the key components of the wheel and axle which is one of the six simple machines. Wheels, in conjunction with axles, allow heavy objects to be moved easily facilitating movement or transportation while supporting a load, or performing labor in machines. Wheels are also used for other purposes, such as a ship’s wheel, steering wheel, potter’s wheel, and flywheel.
Common examples can be found in transport applications. A wheel reduces friction by facilitating motion by rolling together with the use of axles. In order for wheels to rotate, a moment needs to be applied to the wheel about its axis, either by way of gravity or by the application of another external force or torque.
Terminology
The English word wheel comes from the Old English word hwēol, from Proto-Germanic *hwehwlaz, from Proto-Indo-European *kwékwlos,[1] an extended form of the root *kwel- ‘to revolve, move around’. Cognates within Indo-European include Icelandichjól ‘wheel, tyre’, Greek κύκλος kúklos, and Sanskritchakra, the last two both meaning ‘circle’ or ‘wheel’.[2]
History
The place and time of the invention of the wheel remains unclear, because the oldest hints do not guarantee the existence of real wheeled transport,[clarification needed] or are dated with too much scatter.
The invention of the solid wooden disk wheel falls into the late Neolithic, and may be seen in conjunction with other technological advances that gave rise to the early Bronze Age. This implies the passage of several wheel-less millennia even after the invention of agriculture and of pottery, during the Aceramic Neolithic.
4500–3300 BCE (Copper Age): invention of the potter’s wheel; earliest solid wooden wheels (disks with a hole for the axle); earliest wheeled vehicles
The Halaf culture of 6500–5100 BCE is sometimes credited with the earliest depiction of a wheeled vehicle, but there is no evidence of Halafians using either wheeled vehicles or pottery wheels.[3] Potter’s wheels are thought to have been used in the 4th millennium BCE in the Middle East.[4] The oldest surviving example of a potter’s wheel was thought to be one found in Ur (modern day Iraq) dating to approximately 3100 BCE.[5] However, a potter’s wheel found in western Ukraine, of the Cucuteni–Trypillia culture, dates to the middle of the 5th millennium BCE which pre-dates the earliest use of the potter’s wheel in Mesopotamia.[6][7][8][9][10][11] Wheels of uncertain dates have been found in the Indus Valley civilization of the late 4th millennium BCE covering areas of present-day India and Pakistan.[12]
The oldest indirect evidence of wheeled movement was found in the form of miniature clay wheels north of the Black Sea before 4000 BCE. From the middle of the 4th millennium BCE onward, the evidence is condensed throughout Europe in the form of toy cars, depictions, or ruts, with the oldest find in Northern Germany dating back to around 3400 BCE.[13][14][15] In Mesopotamia, depictions of wheeled wagons found on clay tabletpictographs at the Eanna district of Uruk, in the Sumerian civilization are dated to c. 3500–3350 BCE.[16] In the second half of the 4th millennium BCE, evidence of wheeled vehicles appeared near-simultaneously in the Northern (Maykop culture) and South Caucasus and Eastern Europe (Cucuteni-Trypillian culture).
Depictions of a wheeled vehicle appeared between 3631 and 3380 BCE in the Bronocice clay pot excavated in a Funnelbeaker culture settlement in southern Poland.[17] In nearby Olszanica, a 2.2 m wide door was constructed for wagon entry; this barn was 40 m long with three doors, dated to 5000 BCE, and belonged to the NeolithicLinear Pottery culture.[citation needed] Surviving evidence of a wheel-axle combination, from Stare Gmajne near Ljubljana in Slovenia (Ljubljana Marshes Wooden Wheel), is dated within two standard deviations to 3340–3030 BCE, the axle to 3360–3045 BCE.[18] Two types of early Neolithic European wheel and axle are known: a circumalpine type of wagon construction (the wheel and axle rotate together, as in Ljubljana Marshes Wheel), and that of the Baden culture in Hungary (axle does not rotate). They both are dated to c. 3200–3000 BCE.[19] Some historians believe that there was a diffusion of the wheeled vehicle from the Near East to Europe around the mid-4th millennium BCE.[20]
Early wheels were simple wooden disks with a hole for the axle. Some of the earliest wheels were made from horizontal slices of tree trunks. Because of the uneven structure of wood, a wheel made from a horizontal slice of a tree trunk will tend to be inferior to one made from rounded pieces of longitudinal boards.
The spoked wheel was invented more recently and allowed the construction of lighter and swifter vehicles. The earliest known examples of wooden spoked wheels are in the context of the Sintashta culture, dating to c. 2000 BCE (Krivoye Lake). Soon after this, horse cultures of the Caucasus region used horse-drawn spoked-wheel war chariots for the greater part of three centuries. They moved deep into the Greek peninsula where they joined with the existing Mediterranean peoples to give rise, eventually, to classical Greece after the breaking of Minoan dominance and consolidations led by pre-classical Sparta and Athens. Celtic chariots introduced an iron rim around the wheel in the 1st millennium BCE.
In China, wheel tracks dating to around 2200 BCE have been found at Pingliangtai, a site of the Longshan Culture.[21] Similar tracks were also found at Yanshi, a city of the Erlitou culture, dating to around 1700 BCE. The earliest evidence of spoked wheels in China comes from Qinghai, in the form of two wheel hubs from a site dated between 2000 and 1500 BCE.[22]Wheeled vehicles were introduced to China from the west.[23][24][25]
In Britain, a large wooden wheel, measuring about 1 m (3.3 ft) in diameter, was uncovered at the Must Farm site in East Anglia in 2016. The specimen, dating from 1,100 to 800 BCE, represents the most complete and earliest of its type found in Britain. The wheel’s hub is also present. A horse’s spine found nearby suggests the wheel may have been part of a horse-drawn cart. The wheel was found in a settlement built on stilts over wetland, indicating that the settlement had some sort of link to dry land.[26]
A figurine featuring the New World‘s independently invented wheel. Among the places where wheeled toys were found, Mesoamerica is the only one where the wheel was never put to practical use before the 16th century.
Although large-scale use of wheels did not occur in the Americas prior to European contact, numerous small wheeled artifacts, identified as children’s toys, have been found in Mexican archeological sites, some dating to approximately 1500 BCE.[27] Some argue that the primary obstacle to large-scale development of the wheel in the Americas was the absence of domesticated large animals that could be used to pull wheeled carriages.[28] The closest relative of cattle present in Americas in pre-Columbian times, the American bison, is difficult to domesticate and was never domesticated by Native Americans; several horse species existed until about 12,000 years ago, but ultimately became extinct.[29] The only large animal that was domesticated in the Western hemisphere, the llama, a pack animal, was not physically suited to use as a draft animal to pull wheeled vehicles,[30] and use of the llama did not spread far beyond the Andes by the time of the arrival of Europeans.
On the other hand, Mesoamericans never developed the wheelbarrow, the potter’s wheel, nor any other practical object with a wheel or wheels.[31][32] Although present in a number of toys, very similar to those found throughout the world and still made for children today (“pull toys”),[31][32] the wheel was never put into practical use in Mesoamerica before the 16th century.[31][32] Possibly the closest the Mayas came to the utilitarian wheel is the spindle whorl, and some scholars believe that these toys were originally made with spindle whorls and spindle sticks as “wheels” and “axes”.[32]
Aboriginal Australians traditionally used circular discs rolled along the ground for target practice.[33]
Nubians from after about 400 BCE used wheels for spinning pottery and as water wheels.[34] It is thought that Nubian waterwheels may have been ox-driven.[35] It is also known that Nubians used horse-drawn chariots imported from Egypt.[36]
Starting from the 18th century in West Africa, wheeled vehicles were mostly used for ceremonial purposes in places like Dahomey.[37] The wheel was barely used for transportation, with the exception of Ethiopia and Somalia in Sub-Saharan Africa well into the 19th century.[38][37]
The spoked wheel was in continued use without major modification until the 1870s, when wire-spoked wheels and pneumatic tires were invented.[39] Pneumatic tires can greatly reduce rolling resistance and improve comfort. Wire spokes are under tension, not compression, making it possible for the wheel to be both stiff and light. Early radially-spoked wire wheels gave rise to tangentially-spoked wire wheels, which were widely used on cars into the late 20th century. Cast alloy wheels are now more commonly used; forged alloy wheels are used when weight is critical.
This section is about the application to transport. For the simple machine, see Wheel and axle.
A wheeled vehicle requires much less work to move than simply dragging the same weight. The low resistance to motion is explained by the fact that the frictional work done is no longer at the surface that the vehicle is traversing, but in the bearings. In the simplest and oldest case the bearing is just a round hole through which the axle passes (a “plain bearing“). Even with a plain bearing, the frictional work is greatly reduced because:
The normal force at the sliding interface is same as with simple dragging.
The sliding distance is reduced for a given distance of travel.
The coefficient of friction at the interface is usually lower.
Example:
If a 100 kg object is dragged for 10 m along a surface with the coefficient of frictionμ = 0.5, the normal force is 981 N and the work done (required energy) is (work=force x distance) 981 × 0.5 × 10 = 4905 joules.
Now give the object 4 wheels. The normal force between the 4 wheels and axles is the same (in total) 981 N. Assume, for wood, μ = 0.25, and say the wheel diameter is 1000 mm and axle diameter is 50 mm. So while the object still moves 10 m the sliding frictional surfaces only slide over each other a distance of 0.5 m. The work done is 981 × 0.25 × 0.5 = 123 joules; the work done has reduced to 1/40 of that of dragging.
Additional energy is lost from the wheel-to-road interface. This is termed rolling resistance which is predominantly a deformation loss. It depends on the nature of the ground, of the material of the wheel, its inflation in the case of a tire, the net torque exerted by the eventual engine, and many other factors.
A wheel can also offer advantages in traversing irregular surfaces if the wheel radius is sufficiently large compared to the irregularities.
The wheel alone is not a machine, but when attached to an axle in conjunction with bearing, it forms the wheel and axle, one of the simple machines. A driven wheel is an example of a wheel and axle. Wheels pre-date driven wheels by about 6000 years, themselves an evolution of using round logs as rollers to move a heavy load—a practice going back in pre-history so far that it has not been dated.
Construction
This section is about the structure of a wheel. For the making of wire-spoked wheels, see Wheelbuilding. For the making of non-wire spoked wheels, see Wheel construction.
The rim is the “outer edge of a wheel, holding the tire”.[40] It makes up the outer circular design of the wheel on which the inside edge of the tire is mounted on vehicles such as automobiles. For example, on a bicycle wheel the rim is a large hoop attached to the outer ends of the spokes of the wheel that holds the tire and tube.
In the 1st millennium BCE an iron rim was introduced around the wooden wheels of chariots.
Hub
The hub is the center of the wheel, and typically houses a bearing, and is where the spokes meet.
A hubless wheel (also known as a rim-rider or centerless wheel) is a type of wheel with no center hub. More specifically, the hub is actually almost as big as the wheel itself. The axle is hollow, following the wheel at very close tolerances.
A spoke is one of some number of rods radiating from the center of a wheel (the hub where the axle connects), connecting the hub with the round traction surface. The term originally referred to portions of a log which had been split lengthwise into four or six sections. The radial members of a wagon wheel were made by carving a spoke (from a log) into their finished shape. A spokeshave is a tool originally developed for this purpose. Eventually, the term spoke was more commonly applied to the finished product of the wheelwright‘s work, than to the materials used.
The rims of wire wheels (or “wire spoked wheels”) are connected to their hubs by wire spokes. Although these wires are generally stiffer than a typical wire rope, they function mechanically the same as tensioned flexible wires, keeping the rim true while supporting applied loads.
Wire wheels are used on most bicycles and still used on many motorcycles. They were invented by aeronautical engineer George Cayley and first used in bicycles by James Starley. A process of assembling wire wheels is described as wheelbuilding.
A tire (in American English and Canadian English) or tyre (in some Commonwealth Nations such as UK, India, South Africa, Australia and New Zealand) is a ring-shaped covering that fits around a wheel rim to protect it and enable better vehicle performance by providing a flexible cushion that absorbs shock while keeping the wheel in close contact with the ground. The word itself may be derived from the word “tie”, which refers to the outer steel ring part of a wooden cart wheel that ties the wood segments together (see Etymology above).
The fundamental materials of modern tires are synthetic rubber, natural rubber, fabric, and wire, along with other compound chemicals. They consist of a tread and a body. The tread provides traction while the body ensures support. Before rubber was invented, the first versions of tires were simply bands of metal that fitted around wooden wheels to prevent wear and tear. Today, the vast majority of tires are pneumaticinflatable structures, comprising a doughnut-shaped body of cords and wires encased in rubber and generally filled with compressed air to form an inflatable cushion. Pneumatic tires are used on many types of vehicles, such as cars, bicycles, motorcycles, trucks, earthmovers, and aircraft.
Protruding or covering attachments
Extreme off-road conditions have resulted in the invention of several types of wheel cover, which may be constructed as removable attachments or as permanent covers. Wheels like this are no longer necessarily round, or have panels that make the ground-contact area flat.
Examples include:
Snow chains – Specially designed chain assemblies that wrap around the tire to provide increased grip, designed for deep snow.[41]
Dreadnaught wheel – A type of permanently attached hinged panels for general extreme off-road use. These are not connected directly to the wheels, but to each other.
Pedrail wheel – A system of rails that holds panels that hold the vehicle. These do not necessarily have to be built as a circle (wheel) and are thus also a form of Continuous track.
A version of the above examples (name unknown to the writer) was commonly used on heavy artillery during World War I. Specific examples: Cannone da 149/35 A and the Big Bertha. These were panels that were connected to each other by multiple hinges and could be installed over a contemporary wheel.
Continuous track – A system of linked and hinged chains/panels that cover multiple wheels in a way that allows the vehicles mass to be distributed across the space between wheels that are positioned in front of / behind other wheels.
“Tire totes” – A bag designed to cover a tire to improve traction in deep snow.[42][43]
Truck and bus wheels may block (stop rotating) under certain circumstances, such as brake system failure. To help detect this, they sometimes feature “wheel rotation indicators”: colored strips of plastic attached to the rim and protruding out from it, such that they can be seen by the driver in the side-view mirrors. These devices were invented and patented in 1998 by a Canadian truck shop owner.[44]
Alternatives
While wheels are very widely used for ground transport, there are alternatives, some of which are suitable for terrain where wheels are ineffective. Alternative methods for ground transport without wheels include:
The wheel has also become a strong cultural and spiritual metaphor for a cycle or regular repetition (see chakra, reincarnation, Yin and Yang among others). As such and because of the difficult terrain, wheeled vehicles were forbidden in old Tibet. The wheel in ancient China is seen as a symbol of health and strength and used by some villages as a tool to predict future health and success. The diameter of the wheel is indicator of one’s future health. The Kalachakra or wheel of time is also a subject in some forms of Buddhism, along with the dharmachakra.[45][46]
The introduction of spoked (chariot) wheels in the Middle Bronze Age appears to have carried somewhat of a prestige. The sun cross appears to have a significance in Bronze Age religion, replacing the earlier concept of a solar barge with the more ‘modern’ and technologically advanced solar chariot. The wheel was also a solar symbol for the Ancient Egyptians.[47]
In modern usage, the ‘invention of the wheel’ can be considered as a symbol of one of the first technologies of early civilization, alongside farming and metalwork, and thus be used as a benchmark to grade the level of societal progress.[citation needed]
A doughnut (sometimes spelled donut in American English; both /ˈdoʊnət/) is a type of pastry made from leavened fried dough.[1][2]: 275 It is popular in many countries and is prepared in various forms as a sweet snack that can be homemade or purchased in bakeries, supermarkets, food stalls, and franchised specialty vendors. Doughnut is the traditional spelling, while donut is the simplified version; the terms are used interchangeably.
Doughnuts are usually deep fried from a flour dough, but other types of batters can also be used. Various toppings and flavors are used for different types, such as sugar, chocolate or maple glazing. Doughnuts may also include water, leavening, eggs, milk, sugar, oil, shortening, and natural or artificial flavors.
The two most common types are the ring doughnut and the filled doughnut, which is injected with fruit preserves (the jelly doughnut), cream, custard, or other sweet fillings. Small pieces of dough are sometimes cooked as doughnut holes. Once fried, doughnuts may be glazed with a sugar icing, spread with icing or chocolate, or topped with powdered sugar, cinnamon, sprinkles or fruit. Other shapes include balls, flattened spheres, twists, and other forms. Doughnut varieties are also divided into cake (including the old-fashioned) and yeast-risen doughnuts. Doughnuts are often accompanied by coffee or milk. They are sold at doughnut shops, supermarkets, convenience stores, petrol/gas stations, cafes or fast food restaurants.
The cookbook Küchenmeisterei (Mastery of the Kitchen), published in Nuremberg in 1485, offers a recipe for “Gefüllte Krapfen”, stuffed, fried dough cakes.[5]
The Spanish and Portuguese churro is a choux pastry dough that would also be served in a ring-shape. The recipe may have been brought from, or introduced to China, in the 16th century.[6][7]
Dutch settlers brought olykoek (“oil(y) cake”) to New York (or New Amsterdam) in the early 18th century. These doughnuts closely resembled later ones but did not yet have their current ring shape.[8][9][10]
A recipe for fried dough “nuts” was published, in 1750 England, under the title “How to make Hertfordshire Cakes, Nuts and Pincushions”, in The Country Housewife’s Family Companion by William Ellis.[11][12]
A recipe labelled “dow nuts”, again from Hertfordshire, was found in a book of recipes and domestic tips written around 1800, by the wife of Baron Thomas Dimsdale,[13] the recipe being given to the dowager Baroness by an acquaintance who transcribed for her the cooking instructions for a “dow nut”.[14]
The first cookbook using the near conventional “dough nuts” spelling was possibly the 1803 edition of “The Frugal Housewife: Or, Complete Woman Cook”, which included dough nuts in an appendix of American recipes.[15]
One of the earliest mentions of “dough-nut” was in Washington Irving‘s 1809 book A History of New York, from the Beginning of the World to the End of the Dutch Dynasty:[16]
Sometimes the table was graced with immense apple-pies, or saucers full of preserved peaches and pears; but it was always sure to boast of an enormous dish of balls of sweetened dough, fried in hog’s fat, and called dough-nuts, or oly koeks: a delicious kind of cake, at present scarce known in this city, excepting in genuine Dutch families.
The name oly koeks was almost certainly related to the oliekoek: a Dutch delicacy of “sweetened cake fried in fat.”[17]
Etymology
Look up doughnut or donut in Wiktionary, the free dictionary.
“Dough nut”
One of the earliest known literary usages of the term dates to an 1808 short story[18] describing a spread of “fire-cakes and dough-nuts”. Washington Irving described “dough-nuts”, in his 1809 History of New York, as “balls of sweetened dough, fried in hog’s fat, and called dough-nuts, orolykoeks.”[19] These “nuts” of fried dough might now be called doughnut holes. The word nut is here used in the earlier sense of “small rounded cake or cookie”, also seen in ginger nut.[20]Doughnut is the traditional spelling and still dominates even in the United States[21][22][23] though donut is often used.[24][25] At present, doughnut and the shortened form donut are both pervasive in American English.[26]
“Donut”
The first known printed use of donut was in Peck’s Bad Boy and his Pa by George W. Peck, published in 1900, in which a character is quoted as saying, “Pa said he guessed he hadn’t got much appetite, and he would just drink a cup of coffee and eat a donut.”[27] According to author John T. Edge the alternative spelling “donut” was invented in the 1920s when the New York–based Display Doughnut Machine Corporation abbreviated the word to make it more pronounceable by the foreigners they hoped would buy their automated doughnut making equipment.[28] The donut spelling also showed up in a Los Angeles Times article dated August 10, 1929 in which Bailey Millard jokingly complains about the decline of spelling, and that he “can’t swallow the ‘wel-dun donut’ nor the ever so ‘gud bred’”.
The interchangeability of the two spellings can be found in a series of “National Donut Week” articles in The New York Times that covered the 1939 World’s Fair. In four articles beginning 9 October, two mention the donut spelling. Dunkin’ Donuts, which was so-named in 1950, following its 1948 founding under the name Open Kettle (Quincy, Massachusetts), is the oldest surviving company to use the donut variation; other chains, such as the defunct Mayflower Doughnut Corporation (1931), did not use that spelling.[29] According to the Oxford Dictionaries while “doughnut” is used internationally, the spelling “donut” is American.[30] The spelling “donut” remained rare until the 1950s, and has since grown significantly in popularity.[31]
Types
Clockwise from upper left: doughnuts in two shapes; doughnut holes; orange Halloween doughnuts; and a pink Christmas doughnut
Rings
Hanson Gregory, an American, claimed to have invented the ring-shaped doughnut in 1847 aboard a lime-trading ship when he was 16 years old. Gregory was dissatisfied with the greasiness of doughnuts twisted into various shapes and with the raw center of regular doughnuts. He claimed to have punched a hole in the center of dough with the ship’s tin pepper box, and to have later taught the technique to his mother.[32]Smithsonian Magazine states that his mother, Elizabeth Gregory, “made a wicked deep-fried dough that cleverly used her son’s spice cargo of nutmeg and cinnamon, along with lemon rind,” and “put hazelnuts or walnuts in the center, where the dough might not cook through”, and called the food ‘doughnuts’.[8]
Ring doughnuts are formed by one of two methods: by joining the ends of a long, skinny piece of dough into a ring, or by using a doughnut cutter, which simultaneously cuts the outside and inside shape, leaving a doughnut-shaped piece of dough and a doughnut hole (the dough removed from the center). This smaller piece of dough can be cooked and served as a “doughnut hole” or added back to the batch to make more doughnuts. A disk-shaped doughnut can also be stretched and pinched into a torus until the center breaks to form a hole. Alternatively, a doughnut depositor can be used to place a circle of liquid dough (batter) directly into the fryer.
There are two types of ring doughnuts, those made from a yeast-based dough for raised doughnuts, or those made from a special type of cake batter.[12][33][34] Yeast-raised doughnuts contain about 25% oil by weight, whereas cake doughnuts’ oil content is around 20%, but have extra fat included in the batter before frying. Cake doughnuts are fried for about 90 seconds at approximately 190 to 198 °C (374 to 388 °F), turning once. Yeast-raised doughnuts absorb more oil because they take longer to fry, about 150 seconds, at 182 to 190 °C (360 to 374 °F). Cake doughnuts typically weigh between 24 and 28 g (0.85 and 0.99 oz), whereas yeast-raised doughnuts average 38 g (1.3 oz) and are generally larger, and taller (due to rising) when finished.[citation needed]
Daniela Galarza, for Eater, wrote that “the now-standard doughnut’s hole is still up for debate. Food writer Michael Krondl surmises that the shape came from recipes that called for the dough to be shaped like a jumble – a once common ring-shaped cookie. In Cuisine and Culture: A History of Food and People, culinary historian Linda Civitello writes that the hole was invented because it allowed the doughnuts to cook faster. By 1870 doughnut cutters shaped in two concentric circles, one smaller than the other, began to appear in home-shopping catalogues”.[12]
Topping
The process of glazing doughnuts
After frying, ring doughnuts are often topped. Raised doughnuts are generally covered with a glaze (icing). Cake doughnuts can also be glazed, powdered with confectioner’s sugar, or covered with cinnamon and granulated sugar. They are also often topped with cake frosting (top only) and sometimes sprinkled with coconut, chopped peanuts, or sprinkles.
Holes
Doughnut holes are small, bite-sized doughnuts that were traditionally made from the dough taken from the center of ring doughnuts. Before long, doughnut sellers saw the opportunity to market “holes” as a novelty and many chains offer their own variety, some with their own brand names such as “Munchkins” from Dunkin’ Donuts[35][36] and “Timbits” from Tim Hortons.[37]
Traditionally, doughnut holes are made by frying the dough removed from the center portion of the doughnut.[38] Consequently, they are considerably smaller than a standard doughnut and tend to be spherical. Similar to standard doughnuts, doughnut holes may be topped with confections, such as glaze or powdered sugar.
Originally, most varieties of doughnut holes were derivatives of their ring doughnut (yeast-based dough or cake batter) counterparts. However, doughnut holes can also be made by dropping a small ball of dough into hot oil from a specially shaped nozzle or cutter.[39] This production method has allowed doughnut sellers to produce bite-sized versions of non-ring doughnuts, such as filled doughnuts, fritters and Dutchies.
Filled
Filled doughnuts are flattened spheres injected with fruit preserves, cream, custard, or other sweet fillings, and often dipped into powdered sugar or topped off with frosting. Common varieties include the Boston cream, coconut, key lime, and jelly.
Other shapes
Others include the fritter and the Dutchie, which are usually glazed. These have been available on Tim Hortons‘ doughnut menu since the chain’s inception in 1964,[40] and a 1991 Toronto Star report found these two were the chain’s most popular type of fried dough in Canada.[41]
There are many other specialized doughnut shapes such as old-fashioned, bars or Long Johns (a rectangular shape), or twists. Other shapes include balls, flattened spheres, twists, and other forms.[42][43][12] In the northeast United States, bars and twists are usually referred to as crullers. Another is the beignet, a square-shaped doughnut covered with powdered sugar, commonly associated with New Orleans.
Science
Cake vs yeast style
Yeast doughnuts and cake doughnuts contain most of the same ingredients, however, their structural differences arise from the type of flour and leavening agent used. In cake doughnuts, cake flour is used, and the resulting doughnut has a different texture because cake flour has a relatively low protein content of about 7 to 8 percent.[44] In yeast doughnuts, a flour with a higher protein content of about 9 to 12 percent is used, resulting in a doughnut that is lighter and more airy.[44] In addition, yeast doughnuts utilize yeast as a leavening agent. Specifically, “Yeast cells are thoroughly distributed throughout the dough and begin to feed on the sugar that is present … carbon dioxide gas is generated, which raises the dough, making it light and porous.”[45] Whereas this process is biological, the leavening process in cake doughnuts is chemical. In cake doughnuts, the most common leavening agent is baking powder. Baking powder is essentially “baking soda with acid added. This neutralizes the base and produces more CO2 according to the following equation: NaHCO3 + H+ → Na+ + H2O + CO2.“[46]
Physical structure
The physical structure of the doughnut is created by the combination of flour, leavening agent, sugar, eggs, salt, water, shortening, milk solids, and additional components.[2]: 232 [47][48][42][43] The most important ingredients for creating the dough network are the flour and eggs. The main protein in flour is gluten, which is overall responsible for creating elastic dough because this protein acts as “coiled springs.”[49] The gluten network is composed of two separate molecules named glutenin and gliadin. Specifically, “the backbone of the gluten network likely consists of the largest glutenin molecules, or subunits, aligned and tightly linked to one another. These tightly linked glutenin subunits associate more loosely, along with gliadin, into larger gluten aggregates.”[50] The gluten strands then tangle and interact with other strands and other molecules, resulting in networks that provide the elasticity of the dough. In mixing, the gluten is developed when the force of the mixer draws the gluten from the wheat endosperm, allowing the gluten matrix to trap the gas cells.[49]
Molecular composition
A diagram of a phospholipid molecule, which is responsible for the emulsifying properties of lecithin in egg yolk
Eggs function as emulsifiers, foaming agents, and tenderizers in the dough. The egg white proteins, mainly ovalbumin, “function as structure formers. Egg solids, chiefly the egg white solids combined with the moisture in the egg, are considered structure-forming materials that help significantly to produce proper volume, grain, and texture.”[45] The egg yolk contributes proteins, fats, and emulsifiers to the dough. Emulsifying agents are essential to doughnut formation because they prevent the fat molecules from separating from the water molecules in the dough. The main emulsifier in egg yolk is called lecithin, which is a phospholipid. “The fatty acids are attracted to fats and oils (lipids) in food, while the phosphate group is attracted to water. It is this ability to attract both lipids and water that allow phospholipids such as lecithin to act as emulsifiers.”[50] The proteins from both the egg yolk and the egg whites contribute to the structure of the dough through a process called coagulation. When heat is applied to the dough, the egg proteins will begin to unfold, or denature, and then form new bonds with one another, thus creating a gel-like network that can hold water and gas.[50]
An animated sucrose molecule, which is a disaccharide, responsible for the sweetness of a doughnut
Shortening is responsible for providing tenderness and aerating the dough. In terms of its molecular structure, “a typical shortening that appears solid [at room temperature] contains 15–20% solids and, hence, 80–85% liquid oil … this small amount of solids can be made to hold all of the liquid in a matrix of very small, stable, needlelike crystals (beta-prime crystals).”[45] This crystalline structure is considered highly stable due to how tightly its molecules are packed. The sugar used in baking is essentially sucrose, and besides imparting sweetness in the doughnut, sugar also functions in the color and tenderness of the final product. Sucrose is a simple carbohydrate whose structure is made up of a glucose molecule bound to a fructose molecule.[50] Milk is utilized in the making of doughnuts, but in large scale bakeries, one form of milk used is nonfat dry milk solids. These solids are obtained by removing most of the water from skim milk with heat, and this heat additionally denatures the whey proteins and increases the absorption properties of the remaining proteins.[50] The ability of the casein and whey proteins to absorb excess water is essential to prolonging the doughnut’s freshness. The major whey protein in the nonfat milk solids is known as beta-lactoglobulin, and a crucial feature of its structure is that there exists a single sulfhydryl group that is protected by the alpha helix, and when heating of the milk solids occurs, these groups participate in disulfide exchanges with other molecules. This interchange prevents the renaturation of the whey proteins.[51] If the crosslinking of the sulfide groups does not occur, the whey proteins can rebond and weaken the gluten network.
Water is a necessary ingredient in the production of doughnuts because it activates the other ingredients, allowing them to perform their functions in building the doughnut’s structure. For example, sugar and salt crystals must be dissolved in order for them to act in the dough, whereas larger molecules, such as the starches or proteins, must be hydrated in order for them to absorb moisture.[50] Another important consideration of water is its degree of hardness, which measures the amount of impurities in the water source. Pure water consists of two parts hydrogen and one part oxygen, but water used in baking often is not pure. Baker’s salt (NaCl) is usually used as an ingredient due to its high purity, whereas the salts in water are derived from varying minerals. As an ingredient, “salt is added to enhance the flavour of cakes and breads and to ‘toughen up’ the soft mixture of fat and sugar.”[46] If relatively soft water is being used, more salt should be added in order to strengthen the gluten network of the dough, but if not enough salt is added during the baking process, the flavor of the bread will not be appealing to consumers.
An important property of the dough that affects the final product is the dough’s rheology. This property measures the ability of the dough to flow. It can be represented by the power law equation: τ=kDn where τ is the tangentic stress, k is the viscosity coefficient, D is the shear rate, and n is the flow index.[55] Many factors affect dough rheology including the type and volume of ingredients and the force applied during mixing. Dough is usually described as a viscoelastic material, meaning that its rheology depends on both the viscosity and the elasticity. The viscosity coefficient and the flow index are unique to the type of dough being analyzed, while the tangential stress and the shear rate are measurements which depend on the type of force being applied to the dough.[citation needed]
Nom kong (នំបុ័ងកង់), the traditional Cambodian doughnut, is named after its shape – the word ‘កង់’ (pronounced kong in Khmer) literally means “wheel”, whilst nom (‘នំបុ័ង’) is the general word for pastry or any kind of starchy food. A very inexpensive treat for everyday Cambodians, this sweet pastry consists of a jasmine rice flour dough moulded into a classic ring shape and then deep fried in fat, then drizzled with a palm sugar toffee and sprinkled with sesame seeds. The rice flour gives it a chewy texture that Cambodians are fond of. This childhood snack is what inspired Cambodian-American entrepreneur Ted Ngoy to build his doughnut empire, inspiring the film The Donut King.
China
A few sweet, doughnut-style pastries are regional in nature. Cantonese cuisine features an oval-shaped pastry called ngàuhleisōu (牛脷酥, lit. “ox-tongue pastry“, due to its tongue-like shape).
A spherical food called saa1 jung (沙翁), which is also similar to a cream puff but denser with a doughnut-like texture and usually prepared with sugar sprinkled on top, is normally available in dim sum Cantonese restaurants. An oilier Beijing variant of this called 高力豆沙, gaoli dousha, is filled with red bean paste; originally, it was made with egg white instead of dough. Many Chinese cultures make a chewy doughnut known as shuangbaotai (雙包胎), which consists of two conjoined balls of dough.
Chinese cuisine features long, deep-fried doughnut sticks that are often quite oily, hence their name in Mandarin, yóutiáo (油條, “oil strips”); in Cantonese, this doughnut-style pastry is called yàuhjagwái (油炸鬼, “ghosts fried in oil”). These pastries are lightly salted and are often served with congee, a traditional rice porridge or soy milk for breakfast.
In India, an old-fashioned sweet called gulgula is made of sweetened, deep-fried flour balls. A leavening agent may or may not be used.[citation needed]
There are a couple of unrelated doughnut-shaped food items. A savory, fried, ring-shaped snack called a vada is often referred to as the Indian doughnut. The vada is made from dal, lentil or potato flours rather than wheat flour.[56] In North India, it is in the form of a bulging disc called dahi-vada, and is soaked in curd, sprinkled with spices and sliced vegetables, and topped with a sweet and sour chutney. In South India, a vada is eaten with sambar and a coconut chutney.
Sweet pastries similar to old-fashioned doughnuts called badushahi and jalebi are also popular. Balushahi, also called badushah, is made from flour, deep fried in clarified butter, and dipped in sugar syrup. Unlike a doughnut, balushahi is dense. A balushahi is ring-shaped, but the well in the center does not go all the way through to form a hole typical of a doughnut. Jalebi, which is typically pretzel-shaped, is made by deep frying batter in oil and soaking it in sugar syrup.[57] A variant of jalebi, called imarti, is shaped with a small ring in the center around which a geometric pattern is arranged.
Along with these Indian variants, typical varieties of doughnuts are also available from U.S. chains such as Krispy Kreme and Dunkin’ Donuts retail outlets, as well as local brands such as Mad Over Donuts and the Donut Baker.[58]
Indonesia
The Indonesian, donat kentang is a potato doughnut, a ring-shaped fritter made from flour and mashed potatoes, coated in powder sugar or icing sugar.[59]
In Japan, an-doughnut (あんドーナッツ, “bean paste doughnut”) is widely available at bakeries. An-doughnut is similar to Germany’s Berliner, except it contains red azuki bean paste.[60][61]Mister Donut is one of the most popular doughnut chains in Japan. Native to Okinawa is a spheroid pastry similar to doughnuts called sata andagi.[62][63]Mochi donuts are “a cross between a traditional cake-like doughnut and chewy mochi dough similar to what’s wrapped around ice cream”.[64] This hybrid confection was originally popularized in Japan by Mister Donut before spreading to the United States via Hawaii.[65][66] The Mister Donut style, also known as “pon de ring”, uses tapioca flour and produces mochi donuts that are easy to pull apart. Another variation developed in the United States uses glutinous rice flour which produces a denser mochi donut akin to Hawaiian-style butter mochi.[65][67][68] Mochi donuts made from glutinous rice flour “typically contain half the amount of calories as the standard cake or yeast doughnut”.[69]
Malaysia
Kuih keria is a hole doughnut made from boiled sweet potato that is mashed. The sweet potato mash is shaped into rings and fried. The hot doughnut is then rolled in granulated sugar. The result is a doughnut with a sugar-crusted skin.[70]
Nepal
Sel roti is a Nepali homemade, ring-shaped, rice doughnut prepared during Tihar, the widely celebrated Hindu festival in Nepal. A semiliquid dough is usually prepared by adding milk, water, sugar, butter, cardamom, and mashed banana to rice flour, which is often left to ferment for up to 24 hours. A sel roti is traditionally fried in ghee.[71]
Pakistan
Doughnuts are available at most bakeries across Pakistan. The Navaz Sharif variety,[citation needed] available mainly in the city of Karachi, is covered in chocolate and filled with cream, similar to a Boston cream. Doughnuts can readily be found at the many Dunkin’ Donuts branches spread across Pakistan.[72]
Local varieties of doughnuts sold by peddlers and street vendors throughout the Philippines are usually made of plain well-kneaded dough, deep-fried in refined coconut oil and sprinkled with refined (not powdered or confectioner’s) sugar. Round versions of this doughnut are known as buñuelos (also spelled bunwelos, and sometimes confusingly known as “bicho-bicho“), similar to the doughnuts in Spain and former Spanish colonies. Indigenous versions of the doughnut also exist, like the cascaron, which is prepared similarly, but uses ground glutinous rice and coconut milk in place of wheat flour and milk.[73][74]
The distinctively shaped shakoy (also known as lubid-lubid), a doughnut variant from the Visayas, in the Philippines
Other native doughnut recipes include the shakoy, kumukunsi, and binangkal. Shakoy or siyakoy from the Visayas islands (also known as lubid-lubid in the northern Philippines) uses a length of dough twisted into a distinctive rope-like shape before being fried. The preparation is almost exactly the same as doughnuts, though there are variants made from glutinous rice flour. The texture can range from soft and fluffy, to sticky and chewy, to hard and crunchy (in the latter case, they are known as pilipit). They are sprinkled with white sugar, but can also be topped with sesame seeds or caramelized sugar.[75][76]Kumukunsi is a jalebi-like native doughnut from the Maguindanao people. It is made with rice flour, duck eggs, and sugar that is molded into rope-like strands and then fried in a loose spiral. It has the taste and consistency of a creamy pancake.[77][78]Binangkal are simple fried dough balls covered in sesame seeds.[79] Other fried dough desserts include the mesh-like lokot-lokot, the fried rice cake panyalam, and the banana fritter maruya, among others.[80][81]
Taiwan
In Taiwan, shuāngbāotāi (雙胞胎, lit. “twins”) is two pieces of dough wrapped together before frying.[82]
Thailand
In Thailand, a popular breakfast food is pa thong ko, also known as Thai donuts, a version of the Chinese yiu ja guoy/youtiao. Often sold from food stalls in markets or by the side of the road, these doughnuts are small, sometimes X-shaped, and sold by the bag full.[83] They are often eaten in the morning with hot Thai tea.
Vietnam
Vietnamese varieties of doughnuts include bánh tiêu, bánh cam, and bánh rán. Bánh tiêu is a sesame-topped, deep-fried pastry that is hallow. It can be eaten alone or cut in half and served with bánh bò, a gelatinous cake, placed inside the pastry. Bánh cam is from Southern Vietnam and is a ball-shaped, deep-fried pastry coated entirely in sesame seeds and containing a mung bean paste filling. Bánh rán is from Northern Vietnam and is similar to bánh cam; however, the difference is that bánh rán is covered with a sugar glaze after being deep-fried and its mung bean paste filling includes a jasmine essence.[citation needed]
Europe
Austria
In Austria, doughnut equivalents are called Krapfen. They are especially popular during Carnival season (Fasching), and do not have the typical ring shape, but instead are solid and usually filled with apricot jam (traditional) or vanilla cream (Vanillekrapfen).[84] A second variant, called Bauernkrapfen are also made of yeast dough, and have a thick outside ring, but are very thin in the middle.[85]
Belgium
In Belgium, the smoutebollen in Dutch, or croustillons in French, are similar to the Dutch kind of oliebollen, but they usually do not contain any fruit, except for apple chunks sometimes. They are typical carnival and fair snacks and are coated with powdered sugar.[86][87]
Czech Republic
Czech koblihy
U.S.-style doughnuts are available in the Czech Republic, but before[clarification needed] they were solid shape and filled with jelly (strawberry or peach). The shape is similar to doughnuts in Germany or Poland. They are called Kobliha (Koblihy in plural). They may be filled with nougat or with vanilla custard. There are now many fillings; cut in half[clarification needed] or non-filled knots with sugar and cinnamon on top.[88]
in Finland, a sweet doughnut is called a munkki (the word also means monk) and are commonly eaten in cafés and cafeteria restaurants. It is sold cold and sometimes filled with jam (like U.S. jelly donuts) or a vanilla sauce. A ring doughnut is also known as donitsi.[89]
A savory form of doughnut is the lihapiirakka (literally meat pie). Made from a doughnut mixture and deep fried, the end product is more akin to a savory doughnut than any pie known in the English-speaking world.[90]
Former Yugoslavia
Doughnuts similar to the Berliner are prepared in the northern Balkans, particularly in Bosnia and Herzegovina, Croatia, North Macedonia and Serbia (pokladnice or krofne). They are also called krofna, krafna or krafne, a name derived from the Austrian Krapfen for this pastry. In Croatia, they are especially popular during Carneval season and do not have the typical ring shape, but instead are solid. Traditionally, they are filled with jam (apricot or plum). However, they can be filled with vanilla or chocolate cream. Other types of doughnuts are uštipci and fritule. [citation needed]
In parts of Germany, the doughnut equivalents are called Berliner (sg. and pl.), but not in the capital city of Berlin itself and neighboring areas, where they are called Pfannkuchen (which is often found misleading by people in the rest of Germany, who use the word Pfannkuchen to describe a pancake, which is also the literal translation of it). Both Berliner and Pfannkuchen are abbreviations of the term Berliner Pfannkuchen, however.
In middle Germany, doughnuts are called Kreppel or Pfannkuchen. In southern Germany, they are also called Krapfen and are especially popular during Carnival season (Karneval/Fasching) in southern and middle Germany and on New Year’s Eve in northern Germany. A Berliner does not have the typical ring shape of a doughnut, but instead is solid and usually filled with jam, while a ring-shaped variant called Kameruner is common in Berlin and eastern Germany. Bismarcks and Berlin doughnuts are also found in Australia, Canada, Denmark, Finland, Switzerland and the United States. Today, U.S.-style doughnuts are also available in Germany, but are less popular than their native counterparts.
Greece
In Greece, a doughnut-like snack called loukoumas (λουκουμάς), which is spherical and soaked in honey syrup, is available. It is often served with sprinkled cinnamon and grated walnuts or sesame seeds.[93][62]
Hungary
Fánk is a sweet traditional Hungarian cake. The most commonly used ingredients are flour, yeast, butter, egg yolk, rum, salt, milk and oil for frying. The dough is allowed to rise for approximately 30 minutes, resulting in an extremely light pastry. Fánk is usually served with powdered sugar and lekvar.
It is supposed[by whom?] that Fánk pastry is of the same origin as German Berliner, Dutch oliebol, and Polish pączki.
In Lithuania, a kind of doughnut called spurgos is widely known. Some spurgos are similar to Polish pączki, but some specific recipes, such as cottage cheese doughnuts (varškės spurgos), were invented independently.[citation needed]
In the Netherlands, oliebollen, referred to in cookbooks as “Dutch doughnuts”, are a type of fritter, with or without raisins or currants, and usually sprinkled with powdered sugar. Variations of the recipe contain slices of apple or other fruits. They are traditionally eaten as part of New Year celebrations.[95][96]
Norway
In Norway, smultring is the prevailing type of doughnut traditionally sold in bakeries, shops, and stalls. However, U.S.-style doughnuts are widely available in larger supermarkets, McDonald’s restaurants, 7-elevens and bakeries. The Berliner is more common than U.S.-style doughnut, and sold in most supermarkets and bakeries alongside smultring doughnuts.
In Poland and parts of the U.S. with a large Polish community, like Chicago and Detroit, the round, jam-filled doughnuts eaten especially—though not exclusively—during the Carnival are called pączki (pronounced [ˈpɔntʂkʲi]). Pączki have been known in Poland at least since the Middle Ages. Jędrzej Kitowicz has described that during the reign of the Augustus III under influence of French cooks who came to Poland at that time, pączki dough fried in Poland has been improved, so that pączki became lighter, spongier, and more resilient.
Portugal
The malasada is a common type of holeless donut created in Portugal. They are made of fried dough. In Madeira and the Azores they are eaten on Fat Tuesday. It is also popular in Hawaii and Cape Cod. The malasada arrived after immigrants came in.[62]
Romania
The Romanian dessert gogoși are fried dough balls similar to filled doughnuts. They are stuffed with chocolate, jam, cheese and other combinations and may be dusted with icing sugar.
In Russia and the other Post-Soviet countries, ponchiki (Russian: пончики, plural form of пончик, ponchik) or pyshki (Russian: пышки, especially in St. Petersburg) are a very popular sweet doughnut, with many fast and simple recipes available in Russian cookbooks for making them at home as a breakfast or coffee pastry.[97]
Slovenia
In Slovenia, a jam-filled doughnut known as krofi, is very popular. It is the typical sweet during Carnival time, but is to be found in most bakeries during the whole year. The most famous krofi come from the village of Trojane in central Slovenia, and are originally filled with apricotjam filling.[98]
In Spain, there are two different types of doughnuts. The first one, simply called donuts, or more traditionally berlinesas, is a U.S.-style doughnut, i.e., a deep-fried, sweet, soft, ring of flour dough.
The second type of doughnut is a traditional pastry called rosquilla or rosquete (the latter name is typical in the Canary Islands), made of fermented dough and fried or baked in an oven. Rosquillas were purportedly introduced in Spain by the Romans.[99] In Spain, there are several variants of them depending on the region where they are prepared and the time of the year they are sold. In some regions they are considered a special pastry prepared only for Easter.[citation needed] Although overall they are more tightly textured and less sweet than U.S.-style doughnuts, they differ greatly in shape, size and taste from one region to another.[citation needed]
The churro is a sweet pastry of deep-fried dough similar to a doughnut but shaped as a long, thin, ribbed cylinder rather than a ring or sphere. Churros are commonly served dusted in sugar as a snack or with a cup of hot chocolate.
Similar to the Finnish munkki, the Swedishmunk is a sweet doughnut commonly eaten as fika along with coffee. It is sold cold and is sometimes filled with jam (U.S. jelly) or a vanilla sauce. A ring doughnut is also known as simply munk.
In Ukraine doughnuts are called pampushky (Ukrainian: пампушки). Pampushky are made of yeast dough containing wheat, rye or buckwheat flour. Traditionally they are baked, but may also be fried. According to William Pokhlyobkin, the technology of making pampushky points to German cuisine, and these buns were possibly created by German colonists in Ukraine.
United Kingdom
Two shop-bought lightly glazed yum-yums on a plate. On average they are 12–14 cm (4.7–5.5 in) in length.
In the United Kingdom, both filled and ring doughnuts are popular, with jam doughnuts and other varieties readily available at supermarkets. In some parts of Scotland, ring doughnuts are referred to as doughrings, with the ‘doughnut’ name being reserved exclusively for the nut-shaped variety. Glazed, twisted rope-shaped doughnuts are known as yum-yums. It is also possible to buy fudge doughnuts in certain regions of Scotland. Fillings include jam, custard, cream, sweet mincemeat, chocolate and apple. Common ring toppings are sprinkle-iced and chocolate.
In Northern Ireland, ring doughnuts are known as gravy rings, gravy being an archaic term for hot cooking oil.
A kurma is a small, sweet, fried cube-shaped or rectangular doughnut which originated in Eastern India but is sold in Trinidad and Tobago.[citation needed]
Costa Rica
A traditional Puntarenas cream-filled doughnut is round and robust, managing to keep the cream inside liquified. They are popular in Costa Rica.
Mexico
The Mexican donas are similar to doughnuts, including the name; the dona is a fried-doughpastry-based snack, commonly covered with powdered brown sugar and cinnamon, white sugar or chocolate.
Doughnuts are ubiquitous in the United States and can be found in most grocery stores, as well as in specialty doughnut shops. They are equally popular in Canada.[100] Canadians eat more doughnuts per capita than any other nation and has more doughnuts shops per capita than any other nation.[101][102]
A popular doughnut in Hawaii is the malassada. Malassadas were brought to the Hawaiian Islands by early Portuguese settlers, and are a variation on Portugal’s filhós. They are small, eggy balls of yeast dough deep-fried and coated in sugar.[62]
Immigrants have brought various doughnut varieties to the United States. To celebrate Fat Tuesday in eastern Pennsylvania, churches sell a potato starch doughnut called a Fastnacht (or Fasnacht). The treats are so popular there that Fat Tuesday is often called Fastnacht Day. The Polish doughnut, the pączki, is popular in U.S. cities with large Polish communities such as Chicago, Milwaukee, and Detroit.
In regions of the country where apples are widely grown, especially the Northeast and Midwest states, cider doughnuts are a harvest season specialty, especially at orchards open to tourists, where they can be served fresh. Cider doughnuts are a cake doughnut with apple cider in the batter. The use of cider affects both the texture and flavor, resulting in a denser, moister product. They are often coated with either granulated, powdered sugar, or cinnamon sugar.[103]
In southern Louisiana, a popular variety of the doughnut is the beignet, a fried, square doughnut served traditionally with powdered sugar. Perhaps the most well-known purveyor of beignets is New Orleans restaurant Cafe Du Monde.
In Quebec, homemade doughnuts called beignes de Noël are traditional Christmas desserts.[104][105]
The Persian zoolbia and bamiyeh are fritters of various shapes and sizes coated in a sugar syrup.[106][62][107][2]: 43, 335 Doughnuts are also made in the home in Iran, referred to as doughnut, even in the plural.[citation needed]
Israel
Israeli sufganiyot in a wide variety of toppings at a bakery in Tel Aviv, Israel
Jelly doughnuts, known as sufganiyah (סופגניה, pl. sufganiyot סופגניות) in Israel, have become a traditional Hanukkah food[108][109] in the recent era, as they are cooked in oil, associated with the holiday account of the miracle of the oil.[62][110] Traditional sufganiyot are filled with red jelly and topped with icing sugar.[109] However, many other varieties exist, with some being filled with dulce de leche (particularly common after the South American aliyah early in the 21st century).
Morocco
In Morocco, Sfenj is a similar pastry eaten sprinkled with sugar or soaked in honey.[111]
Tunisia
In Tunisia, traditional pastries similar to doughnuts are yo-yos. They come in different versions both as balls and in shape of doughnuts. They are deep-fried and covered in a honey syrup or a kind of frosting. Sesame seeds are also used for flavor and decoration along with orange juice and vanilla.
Oceania
Australia
Custard-filled doughnut served by Il Fornaio, St Kilda, Victoria, Australia
In Australia, the doughnut is a popular snack food. Jam doughnuts are particularly popular,[112] especially in Melbourne, Victoria and the Queen Victoria Market, where they are a tradition.[113] Jam doughnuts are similar to a Berliner, but are served hot: red jam (raspberry or strawberry) is injected into the bun before it is deep-fried, and then it is coated with either sugar or sugar mixed with cinnamon as soon as it has been cooked. Jam doughnuts are sometimes also bought frozen. In South Australia, they are known as Berliner or Kitchener and often served in cafes. Popular variants include custard-filled doughnuts, and more recently Nutella-filled doughnuts.
Mobile vans that serve doughnuts, traditional or jam, are often seen at spectator events, markets, carnivals and fetes, and by the roadside near high-traffic areas like airports and the car parks of large shopping centres. Traditional cinnamon doughnuts are readily available in Australia from specialized retailers and convenience stores. Doughnuts are a popular choice for schools and other not-for-profit groups to cook and sell as a fundraiser.
New Zealand
In New Zealand, the doughnut is a popular food snack available in corner dairies. They are in the form of a long sweet bread roll with a deep cut down its long axis. In this cut is placed a long dollop of sweetened clotted cream and on top of this is a spot of strawberry jam. Doughnuts are of two varieties: fresh cream or mock cream. The rounded variety is widely available as well.
South America
Brazil
In Brazil, bakeries, grocery stores and pastry shops sell ball-shaped doughnuts popularly known as “sonhos” (lit. dreams). The dessert was brought to Brazil by Portuguese colonizers that had contact with Dutch and German traders. They are the equivalent of nowadays “bolas de Berlim” (lit. balls of Berlin) in Portugal, but the traditional Portuguese yellow cream was substituted by local dairy and fruit products. They are made of a special type of bread filled with “goiabada” (guava jelly) or milk cream, and covered by white sugar.
Chile
The Berlin (plural Berlines) doughnut is popular in Chile because of the large German community. It may be filled with jam or with manjar, the Chilean version of dulce de leche.[62]
Peru
Peruvian cuisine includes picarones which are doughnut-shaped fritters made with a squash and sweet potato base.[62] These snacks are almost always served with a drizzle of sweet molasses-based sauce.
Sub-Saharan Africa
South Africa
In South Africa, an Afrikaans variation known as the koeksister is popular. Another variation, similar in name, is the Cape Malay koesister being soaked in a spiced syrup and coated in coconut. It has a texture similar to more traditional doughnuts as opposed to the Afrikaans variety.[114] A further variation is the vetkoek, which is also dough deep fried in oil. It is served with mince, syrup, honey or jam.[115]
In popular culture
Police officers in South Korea eating doughnuts. Police officers liking doughnuts is a common stereotype.
The doughnut has made an appearance in popular culture, particularly in the United States and Australia. References extend to objects or actions that are doughnut-shaped.
In film, the doughnut has inspired Dora’s Dunking Doughnuts (1933), The Doughnuts (1963) and Tour de Donut: Gluttons for Punishment. In video games, the doughnut has appeared in games like The Simpsons Game and Donut Dilemma. In the cartoon ¡Mucha Lucha!, there are four things that make up the code of mask wrestling: honor, family, tradition, and doughnuts. Also, in the television sitcom The Simpsons, Homer Simpson‘s love affair with doughnuts is a prominent ongoing joke as well as the focal point of more than a few episodes. In the children’s book Homer Price, Homer’s Uncle Ulysses installs a doughnut making machine in his lunchroom in the fictional town of Centerburg. There is also a children’s book Arnie the Doughnut and music albums The Doughnut in Granny’s Greenhouse.
In films, TV shows, and other popular culture references, police officers are associated with doughnuts,[116] depicted as enjoying them during their coffee break or office hours. This cliché has been parodied in the film Police Academy 4: Citizens on Patrol, where Officer Zed is instructing new recruits how to “properly” consume their doughnuts with coffee. It is also parodied in the television series Twin Peaks, where the police station is always in large supply.[117] In the video gameNeuromancer, there is a Donut World shop, where only policemen are allowed. During a citywide “lockdown” after the Boston Marathon bombing, a handful of selected Dunkin’ Donuts locations were ordered to remain open to serve police and first responders despite the closing of the vast majority of city businesses.[118]
Tim Hortons is the most popular Canadian doughnut and coffee franchise, and one of the most successful quick service restaurants in the country.[original research?] In the Second City Television sketch comedy “The Great White North” featuring the fictional stereotypically Canadian brothers Bob and Doug MacKenzie (and in their film Strange Brew), doughnuts play a role in the duo’s comedy.
Per capita, Canadians consume the most doughnuts, and Canada has the most doughnut stores per capita.[101][102]
United States
Within the United States, the Providence metropolitan area was cited as having the most doughnut shops per capita (25.3 doughnut shops per 100,000 people) as of 13 January 2010.[121]National Doughnut Day celebrates the doughnut’s history and role in popular culture. There is a race in Staunton, Illinois, featuring doughnuts, called the Tour de Donut.
Pink boxes
In the US, especially in Southern California, fresh doughnuts sold by the dozen at local doughnut shops are typically packaged in generic pink boxes. This phenomenon has been attributed to Ted Ngoy and Ning Yen, refugees of the Cambodian genocide who began to transform the local doughnut shop industry in 1976. They proved so adept at the business and in training fellow Chinese Cambodian refugees to follow suit that these local doughnut shops soon dominated native franchises such as Winchell’s Donuts. Ngoy and Yen allegedly planned to purchase boxes of a lucky red color rather than the standard white, but settled on a leftover pink stock because of its lower cost.
In the mid-1970s, pink doughnut boxes were already a common sight in the eastern and midwestern United States, due to the fact that Dunkin’ Donuts used a solid pink color for its boxes at that time.[122] (It switched to a different box design sometime after 1975.) But the chain did not begin to establish a major presence in California until the 2010s.[123]
Owing to the success of Ngoy and Yen’s business, the color soon became a recognizable standard in California. Due to the locality of Hollywood, the pink boxes frequently appeared as film and television props and were thus transmitted into popular culture.[124]
Holidays and festivals
National Doughnut Day
A World War I propaganda poster featuring The Salvation Army’s making of donuts during the war
National Doughnut Day, also known as National Donut Day, celebrated in the United States of America, is on the first Friday of June each year, succeeding the Doughnut Day event created by The Salvation Army in 1938 to honor those of their members who served doughnuts to soldiers during World War I.[125] About 250 Salvation Army volunteers went to France. Because of the difficulties of providing freshly baked goods from huts established in abandoned buildings near the front lines, the two Salvation Army volunteers (Ensign Margaret Sheldon and Adjutant Helen Purviance) came up with the idea of providing doughnuts. These are reported to have been an “instant hit”, and “soon many soldiers were visiting The Salvation Army huts”. Margaret Sheldon wrote of one busy day: “Today I made 22 pies, 300 doughnuts, 700 cups of coffee.” Soon, the women who did this work became known by the servicemen as “Doughnut Dollies”.
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