Honey is a sweet andviscous substance made by several species ofbees, the best-known of which arehoney bees.[1][2] Honey is made and stored to nourish bee colonies. Bees produce honey by gathering and then refining thesugary secretions of plants (primarily floralnectar) or the secretions of other insects, like thehoneydew ofaphids. This refinement takes place both within individual bees, throughregurgitation andenzymatic activity, and during storage in the hive, through water evaporation that concentrates the honey's sugars until it is thick and viscous.
Honey bees stockpile honey in thehive. Within the hive is a structure made from wax calledhoneycomb. The honeycomb is made up of hundreds or thousands ofhexagonal cells, into which the beesregurgitate honey for storage. Other honey-producing species of bee store the substance in different structures, such as the pots made of wax andresin used by thestingless bee.[1][2][3]
Honey for human consumption is collected from wild bee colonies, or from thehives of domesticated bees. The honey produced by honey bees is the most familiar to humans, thanks to its worldwide commercial production and availability.[4] Thehusbandry of bees is known asbeekeeping or apiculture, with the cultivation of stingless bees usually referred to asmeliponiculture.
Honey is sweet because of its high concentrations of themonosaccharidesfructose andglucose. It has about the same relativesweetness assucrose (table sugar).[5][6] One standardtablespoon (15 mL) of honey provides around 190 kilojoules (46 kilocalories) offood energy.[7] It has attractive chemical properties forbaking and a distinctive flavor when used as a sweetener.[5] Mostmicroorganisms cannot grow in honey and sealed honey therefore does notspoil. Samples of honey discovered inarchaeological contexts have proven edible even after millennia.[8][9]
French honey from different floral sources, with visible differences in color and texture
Honey is produced by bees who have collectednectar orhoneydew. Bees value honey for its sugars, which they consume to support generalmetabolic activity, especially that of their flight muscles duringforaging, and as a food for theirlarvae. To this end bees stockpile honey to provide for themselves during ordinary foraging as well as during lean periods, as inoverwintering.[13][14] During foraging bees use part of the nectar they collect to power their flight muscles. The majority of nectar collected is not used to directly nourish the insects but is instead destined forregurgitation,enzymatic digestion, and finally long-termstorage as honey.[13][15] During cold weather or when other food sources are scarce, adult andlarval bees consume stored honey, which is many times more energy-dense as the nectar from which it is made.[14]
After leaving the hive, a foraging bee collects sugar-rich nectar or honeydew. Nectar from the flower generally has a water content of 70 to 80% and is much less viscous than finished honey, which usually has a water content around 18%.[16][17] The water content of honeydew from aphids and othertrue bugs is generally very close to the sap on which those insects feed and is usually somewhat more dilute than nectar. One source describes the water content of honeydew as around 89%.[18] Whether it is feeding on nectar or honeydew, the bee sucks these runny fluids through itsproboscis, which delivers the liquid to the bee's honey stomach or "honey crop".[15] This cavity lies just above its food stomach, the latter of which digests pollen and sugars consumed by an individual honey bee for its own nourishment.
InApis mellifera, the honey stomach holds about 40 mg of liquid. This is about half the weight of an unladen bee. Collecting this quantity in nectar can require visits to more than a thousand flowers. When nectar is plentiful, it can take a bee more than an hour of ceaseless work to collect enough nectar to fill its honey crop.Salivary enzymes and proteins from the bee'shypopharyngeal gland are secreted into the nectar once it is in the bee's honey stomach. Thesesubstances begincleavingcomplex sugars likesucrose andstarches into simpler sugars such asglucose andfructose. This process slightly raises the water content and the acidity of the partially digested nectar.[13][19]
Once filled, the forager bees return to the hive. There they regurgitate and transfer nectar to hive bees. Once it is in their own honey stomachs, the hive bees regurgitate the nectar, repeatedly forming bubbles between theirmandibles, speeding its digestion and concentration. These bubbles create a large surface area per volume and by this means the bees evaporate a portion of the nectar's water into the warm air of the hive.[13][15][20]
Hive bees form honey-processing groups. These groups work in relay, with one bee subjecting the processed nectar to bubbling and then passing the refined liquid on to others. It can take as long as 20 minutes of continuous regurgitation, digestion and evaporation until the product reaches storage quality.[15] The new honey is then placed in honeycomb cells, which are left uncapped. This honey still has a very high water content, up to 70%, depending on the concentration of nectar gathered. At this stage of its refinement the water content of the honey is high enough that ubiquitousyeastspores canreproduce in it, a process which, if left unchecked, would rapidlyconsume the new honey's sugars.[21] To combat this, bees use an ability rare among insects: theendogenous generation of heat.
Bees are among the few insects that can create large amounts of body heat. They use this ability to produce a constant ambient temperature in their hives. Hive temperatures are usually around 35 °C (95 °F) in the honey-storage areas. This temperature is regulated either by generating heat with their bodies or removing it through water evaporation. The evaporation removes water from the stored honey, drawing heat from the colony. The bees use their wings to govern hive cooling. Coordinated wing beating moves air across the wet honey, drawing out water and heat. Ventilation of the hive eventually expels both excess water and heat into the outside world.
The process of evaporating continues until the honey reaches its final water content of between 15.5% to 18%.[16] This concentrates the sugars far beyond thesaturation point of water, which is to say there is far more sugar dissolved in what little water remains in honey than ever could be dissolved in an equivalent volume of water. Honey, even at hive temperatures, is therefore asupercooled solution of various sugars in water. These concentrations of sugar can only be achieved near room temperature by evaporation of a less concentrated solution, in this case nectar. Forosmotic reasons such high concentrations of sugar are extremely unfavorable to microbiological reproduction and allfermentation is consequently halted.[14][15] The bees then cap the cells of finished honey with wax. This seals them from contamination and prevents further evaporation.[15]
So long as its water concentration does not rise much above 18%, honey has an indefinite shelf life, both within the hive and after its removal by abeekeeper.[14]
Human beings havesemi-domesticated several species of honey bee by taking advantage of their swarming stage. Swarming is the means by which new colonies are established when there is no longer space for expansion in the colony's present hive. The old queen lays eggs that will develop into new queens and then leads as many as half the colony to a site for a new hive. Bees generally swarm before a suitable location for another hive has been discovered by scouts sent out for this purpose. Until such a location is found the swarm will simply conglomerate near the former hive, often from tree branches. These swarms are unusually docile and amenable to transport by humans. When provided with a suitable nesting site, such as a commercialLangstroth hive, the swarm will readily form a new colony in artificial surroundings. These semi-domesticated colonies are then looked after by humans practicing apiculture or meliponiculture. Captured bees are encouraged to forage, often in agricultural settings such as orchards, where pollinators are highly valued. The honey,pollen,wax andresins the bees produce are all harvested by humans for a variety of uses.[24]
The term "semi-domesticated" is preferred because all bee colonies, even those in very large agricultural apiculture operations, readily leave the protection of humans in swarms that can establish successful wild colonies. Much of the effort in commercial beekeeping is dedicated to persuading a hive that is ready to swarm to produce more honeycomb in its present location. This is usually done by adding more space to the colony withhoney supers, empty boxes placed on top of an existing colony. The bees can then usually be enticed to develop this empty space instead of dividing their colony through swarming.[25]
Sealed frame of honeyExtraction from a honeycombFiltering from a honeycomb
Honey is collected from wild bee colonies or from domesticated beehives. On average, a hive will produce about 29 kilograms (65 lb) of honey per year.[26] Wild bee nests are sometimes located by following ahoneyguide bird.
To safely collect honey from a hive, beekeepers typically pacify the bees using abee smoker. The smoke triggers a feeding instinct (an attempt to save the resources of the hive from a possible fire), making them less aggressive, and obscures the pheromones the bees use to communicate. The honeycomb is removed from the hive and the honey may be extracted from it either by crushing or by using ahoney extractor. The honey is then usually filtered to remove beeswax and other debris.
Before the invention of removable frames, bee colonies were often sacrificed to conduct the harvest. The harvester would take all the available honey and replace the entire colony the next spring. Since the invention of removable frames, the principles of husbandry led most beekeepers to ensure that their bees have enough stores to survive the winter, either by leaving some honey in the beehive or by providing the colony with a honey substitute such as sugar water or crystalline sugar (often in the form of a "candyboard"). The amount of food necessary to survive the winter depends on the variety of bees and on the length and severity of local winters.
Many animal species are attracted to wild or domestic sources of honey.[27]
Preservation
Because of its composition and chemical properties, honey is suitable for long-term storage, and is easily assimilated even after long preservation. Honey, and objects immersed in honey, have been preserved for centuries.[28][29] (However, no edible honey has been found in Egyptian tombs; all such cases have been proven to be other substances or only chemical traces.[30]) The key to preservation is limiting access to humidity. In its cured state, honey has a sufficiently high sugar content to inhibit fermentation. If exposed to moist air, itshydrophilic properties pull moisture into the honey, eventually diluting it to the point that fermentation can begin.[31]
The longshelf life of honey is attributed to anenzyme found in the stomach of bees. The bees mixglucose oxidase with expelled nectar they previously consumed, creating twobyproducts –gluconic acid andhydrogen peroxide, which are partially responsible for honey acidity and suppression of bacterial growth.[8]
Adulteration
Honey is sometimesadulterated by the addition of other sugars, syrups, or compounds to change its flavor or viscosity, reduce cost, or increase the fructose content to inhibitcrystallization. Honey has been adulterated since ancient times, when honey was sometimes blended with plant syrups such asmaple,birch, orsorghum and sold to customers as pure honey. Sometimes crystallized honey was mixed with flour or other fillers, hiding the adulteration from buyers until the honey was liquefied. In modern times, the most common adulterant became clear, almost-flavorless corn syrup; the adulterated mixture can be very difficult to distinguish from pure honey.[32]
According to theCodex Alimentarius of the United Nations, any product labeled as "honey" or "pure honey" must be a wholly natural product, although labeling laws differ between countries.[33] In the United States, according to the National Honey Board, "Ensuring honey authenticity is one of the great challenges facing the honey industry today. Over the past half century, a number of honey testing methods have been developed to detect food fraud. To date, there is no single universal analytical method available which is capable of detecting all types of adulteration with adequate sensitivity."[34]
Isotope ratio mass spectrometry can be used to detect addition ofcorn syrup andcane sugar by the carbonisotopic signature. Addition of sugars originating from corn or sugar cane (C4 plants, unlike the plants used by bees, and alsosugar beet, which are predominantlyC3 plants) skews the isotopic ratio of sugars present in honey,[34] but does not influence the isotopic ratio of proteins. In an unadulterated honey, the carbon isotopic ratios of sugars and proteins should match. Levels as low as 7% of addition can be detected.[34]
In 2020, global production of honey was 1.8milliontonnes, led by China with 26% of the world total (table).[35] Other major producers wereTurkey,Iran,Argentina, andUkraine.[35]
Over its history as a food,[10] the main uses of honey are in cooking, baking, desserts, as a spread on bread, as an addition to various beverages such as tea, and as a sweetener in some commercial beverages.[36]
Mead varieties include drinks calledmetheglin (with spices or herbs),melomel (with fruit juices, such as grape, specifically calledpyment),hippocras (withcinnamon), and sack mead (high concentration of honey),[41] many of which have been developed as commercial products numbering in the hundreds in the United States.[42] Honey is also used to make meadbeer, called "braggot".[43]
Physical and chemical properties
Crystallized honey: The inset shows a close-up of the honey, showing the individual glucose grains in the fructose mixture.
The physical properties of honey vary, depending on water content, the type of flora used to produce it (pasturage), temperature, and the proportion of the specific sugars it contains. Fresh honey is asupersaturated liquid, containing more sugar than the water can typically dissolve at ambient temperatures. At room temperature, honey is asupercooled liquid, in which the glucose precipitates into solid granules. This forms a semisolid solution ofprecipitated glucosecrystals in a solution of fructose and other ingredients.[citation needed]
Thedensity of honey typically ranges between 1.38 and 1.45 kg/L at 20 °C.[44]
Phase transitions
The melting point of crystallized honey is between 40 and 50 °C (104 and 122 °F), depending on its composition. Below this temperature, honey can be either in ametastable state, meaning that it will not crystallize until aseed crystal is added, or, more often, it is in a "labile" state, being saturated with enough sugars to crystallize spontaneously.[45] The rate of crystallization is affected by many factors, but the primary factor is the ratio of the main sugars: fructose to glucose. Honeys that are supersaturated with a very high percentage of glucose, such asbrassica honey, crystallize almost immediately after harvesting, while honeys with a low percentage of glucose, such as chestnut ortupelo honey, do not crystallize. Some types of honey may produce few but very large crystals, while others produce many small crystals.[46]
Crystallization is also affected by water content, because a high percentage of water inhibits crystallization, as does a highdextrin content. Temperature also affects the rate of crystallization, with the fastest growth occurring between 13 and 17 °C (55 and 63 °F). Crystal nuclei (seeds) tend to form more readily if the honey is disturbed, by stirring, shaking, or agitating, rather than if left at rest. However, thenucleation of microscopic seed-crystals is greatest between 5 and 8 °C (41 and 46 °F). Therefore, larger but fewer crystals tend to form at higher temperatures, while smaller but more-numerous crystals usually form at lower temperatures. Below 5 °C, the honey will not crystallize, thus the original texture and flavor can be preserved indefinitely.[46]
Honey is a supercooled liquid when stored below its melting point, as is normal. At very low temperatures, honey does not freeze solid; rather its viscosity increases. Like mostviscous liquids, the honey becomes thick and sluggish with decreasing temperature. At −20 °C (−4 °F), honey may appear or even feel solid, but it continues to flow at very low rates. Honey has aglass transition between −42 and −51 °C (−44 and −60 °F). Below this temperature, honey enters aglassy state and becomes anamorphous solid (noncrystalline).[47][48]
Rheology
Pouring raw honey. The sheet-like appearance of the flow is the result of high viscosity and low surface tension, contributing to the stickiness of honey.[49][50]
Theviscosity of honey is affected greatly by both temperature and water content. The higher the water percentage, the more easily honeyflows. Above its melting point, however, water has little effect on viscosity. Aside from water content, the composition of most types of honey also has little effect on viscosity. At 25 °C (77 °F), honey with 14% water content generally has a viscosity around 400 poise, while a honey containing 20% water has a viscosity around 20 poise. Viscosity increases very slowly with moderate cooling; a honey containing 16% water, at 70 °C (158 °F), has a viscosity around 2 poise, while at 30 °C (86 °F), the viscosity is around 70 poise. With further cooling, the increase in viscosity is more rapid, reaching 600 poise at around 14 °C (57 °F).[51][52] However, while honey is viscous, it has lowsurface tension of 50–60 mJ/m2, making itswettability similar to water,glycerin, or most other liquids.[53] The high viscosity and wettability of honey causestickiness, which is a time-dependent process in supercooled liquids between the glass-transition temperature (Tg) and the crystalline-melting temperature.[54]
Most types of honey areNewtonian liquids, but a few types havenon-Newtonian viscous properties. Honeys fromheather ormānuka displaythixotropic properties. These types of honey enter a gel-like state when motionless, but liquefy when stirred.[55]
Electrical and optical properties
Because honey containselectrolytes, in the form of acids and minerals, it exhibits varying degrees ofelectrical conductivity. Measurements of the electrical conductivity are used to determine the quality of honey in terms ofash content.[52]
The effect honey has on light is useful for determining the type and quality. Variations in its water content alter itsrefractive index. Water content can easily be measured with arefractometer. Typically, the refractive index for honey ranges from 1.504 at 13% water content to 1.474 at 25%. Honey also has an effect onpolarized light, in that it rotates the polarization plane. The fructose gives a negative rotation, while the glucose gives a positive one. The overall rotation can be used to measure the ratio of the mixture.[52][31] Honey is generally pale yellow and dark brown in color,[citation needed] but other colors can occur, depending on the sugar source.[56] Bee colonies that forage onKudzu (Pueraria montana var.lobata) flowers, for example, produce honey that varies in color from red to purple.[57][better source needed]
Hygroscopy and fermentation
Honey has the ability to absorb moisture directly from the air, a phenomenon calledhygroscopy. The amount of water the honey absorbs is dependent on the relative humidity of the air. Because honey contains yeast, this hygroscopic nature requires that honey be stored in sealed containers to prevent fermentation, which usually begins if the honey's water content rises much above 25%. Honey tends to absorb more water in this manner than the individual sugars allow on their own, which may be due to other ingredients it contains.[31]
Fermentation of honey usually occurs after crystallization, because without the glucose, the liquid portion of the honey primarily consists of a concentrated mixture of fructose, acids, and water, providing the yeast with enough of an increase in the water percentage for growth. Honey that is to be stored at room temperature for long periods of time is oftenpasteurized, to kill any yeast, by heating it above 70 °C (158 °F).[31]
Thermal characteristics
Creamed honey: the honey on the left is fresh, and the honey on the right has been aged at room temperature for two years. The Maillard reaction produces considerable differences in the color and flavor of the aged honey, which remains edible.
Like all sugar compounds, honeycaramelizes if heated sufficiently, becoming darker in color, and eventually burns. However, honey contains fructose, which caramelizes at lower temperatures than glucose.[58] The temperature at which caramelization begins varies, depending on the composition, but is typically between 70 and 110 °C (158 and 230 °F). Honey also contains acids, which act ascatalysts for caramelization. The specific types of acids and their amounts play a primary role in determining the exact temperature.[59] Of these acids, the amino acids, which occur in very small amounts, play an important role in the darkening of honey. The amino acids form darkened compounds calledmelanoidins, during aMaillard reaction. The Maillard reaction occurs slowly at room temperature, taking from a few to several months to show visible darkening, but speeds up dramatically with increasing temperatures. However, the reaction can also be slowed by storing the honey at colder temperatures.[60]
Unlike many other liquids, honey has very poorthermal conductivity of 0.5 W/(m⋅K) at 13% water content (compared to 401 W/(m⋅K) ofcopper), taking a long time to reachthermal equilibrium.[61] Due to its highkinematic viscosity honey does not transfer heat through momentum diffusion (convection) but rather throughthermal diffusion (more like a solid), so melting crystallized honey can easily result in localized caramelization if the heat source is too hot or not evenly distributed. However, honey takes substantially longer to liquefy when just above the melting point than at elevated temperatures.[52] Melting 20 kg (44 lb) of crystallized honey at 40 °C (104 °F) can take up to 24 hours, while 50 kg (110 lb) may take twice as long. These times can be cut nearly in half by heating at 50 °C (122 °F); however, many of the minor substances in honey can be affected greatly by heating, changing the flavor, aroma, or other properties, so heating is usually done at the lowest temperature and for the shortest time possible.[62]
Acid content and flavor effects
The averagepH of honey is 3.9, but can range from 3.4 to 6.1.[63] Honey contains many kinds of acids, bothorganic andamino. However, the different types and their amounts vary considerably, depending on the type of honey. These acids may bearomatic oraliphatic (nonaromatic). The aliphatic acids contribute greatly to the flavor of honey by interacting with the flavors of other ingredients.[63]
Individual honeys from different plant sources contain over 100volatile organic compounds (VOCs), which play a primary role in determining honeyflavors andaromas.[65][66][67] VOCs are carbon-based compounds that readilyvaporize into the air, providing aroma, including the scents of flowers, essential oils, or ripening fruit.[65][67] The typical chemical families of VOCs found in honey includehydrocarbons,aldehydes,alcohols,ketones,esters,acids,benzenes,furans,pyrans,norisoprenoids, andterpenes, among many others and their derivatives.[65][67] The specific VOCs and their amounts vary considerably between different types of honey obtained by bees foraging on different plant sources.[65][66][67] By example, when comparing the mixture of VOCs in different honeys in one review,longan honey had a higher amount of volatiles (48 VOCs), whilesunflower honey had the lowest number of volatiles (8 VOCs).[65]
VOCs are primarily introduced into the honey from the nectar, where they are excreted by the flowers imparting individual scents.[65] The specific types and concentrations of certain VOCs can be used to determine the type of flora used to produce monofloral honeys.[65][67] The specific geography, soil composition and acidity used to grow the flora also have an effect on honey aroma properties,[66] such as a "fruity" or "grassy" aroma from longan honey, or a "waxy" aroma from sunflower honey.[65] Dominant VOCs in one study werelinalooloxide, trans-linalool oxide, 2-phenylacetaldehyde,benzylethanol,isophorone, andmethylnonanoate.[65]
VOCs can also be introduced from the bodies of the bees, be produced by the enzymatic actions of digestion, or from chemical reactions that occur between different substances within the honey during storage, and therefore may change, increase, or decrease over long periods of time.[65][66] VOCs may be produced, altered, or greatly affected by temperature and processing.[66] Some VOCs are heat labile, and are destroyed at elevated temperatures, while others can be created during non-enzymatic reactions, such as theMaillard reaction.[67] VOCs are responsible for nearly all of the aroma produced by a honey, which may be described as "sweet", "flowery", "citrus", "almond" or "rancid", among other terms.[65] In addition, VOCs play a large role in determining the specific flavor of the honey, both through the aromas and flavor.[65] VOCs from honeys in different geographic regions can be used as floral markers of those regions, and as markers of the bees that foraged the nectars.[65][66]
Classification
Honey is classified by its source (floral or not), and divisions are made according to the packaging and processing used.Regional honeys are also identified. In the US, honey is also graded on its color and optical density byUSDA standards, graded on the Pfund scale, which ranges from 0 for "water white" honey to more than 114 for "dark amber" honey.[68]
Plant source
Generally, honey is classified by the floral source of the nectar from which it was made. Honeys can be from specific types of flower nectars or can be blended after collection. The pollen in honey is traceable to floral source and therefore region of origin. Therheological andmelissopalynological properties of honey can be used to identify the major plant nectar source used in its production.[69]
Polyfloral honey, also known as wildflower honey,[72] is derived from the nectar of many types of flowers.[70][73] The taste may vary from year to year, and the aroma and the flavor can be more or less intense, depending on which flowers are blooming.[70]
Honeydew honey
Honeydew honey is made from bees taking direct secretions from trees such aspine,fir,chestnut, andoak or primarilyhoneydew, the sweet secretions ofaphids or other plant-sap-sucking insects, to produce honey rather than fromnectar.[74][75] This honey has a much larger proportion of indigestibles than light floral honeys, thus causingdysentery to the bees.[76] Honeydew honey has a stronger and less sweet flavor than nectar-based honey, and European countries have been the primary market for honeydew honey.[74] In Greece,pine honey, a type of honeydew honey, constitutes 60–65% of honey production.[77]
Classification by packaging and processing
A variety of honey flavors and container sizes and styles from the 2008Texas State Fair
Generally, honey is bottled in its familiar liquid form, but it is sold in other forms, and can be subjected to a variety of processing methods.
Crystallized honey occurs when some of the glucose content has spontaneously crystallized from solution as the monohydrate. It is also called "granulated honey" or "candied honey". Honey that has crystallized (or is commercially purchased crystallized) can be returned to a liquid state by warming.[78] Despite a common misconception, honey crystallizing does not mean it has expired.[79][80]
Pasteurized honey has been heated in apasteurization process which requires temperatures of 72 °C (161 °F) or higher. Pasteurization destroys yeast cells. It also liquefies any microcrystals in the honey, which delays the onset of visible crystallization. However, excessive heat exposure also results in product deterioration, as it increases the level ofhydroxymethylfurfural (HMF)[citation needed] and reduces enzyme (e.g. diastase) activity. Heat also darkens the honey, and affects taste and fragrance.[81]
Raw honey is as it exists in the beehive or as obtained by extraction, settling, or straining, without adding heat (although some honey that has been "minimally processed" is often labeled as raw honey).[82] Raw honey contains some pollen and may contain small particles of wax.
Strained honey has been passed through a mesh material to remove particulate material[83] (pieces of wax,propolis, other defects) without removing pollen, minerals, or enzymes.
Filtered honey of any type has been filtered to the extent that all or most of the fine particles, pollen grains, air bubbles, or other materials normally found in suspension, have been removed.[84] The process typically heats honey to 66–77 °C (150–170 °F) to more easily pass through the filter.[85] Filtered honey is very clear and will not crystallize as quickly,[85] making it preferred by supermarkets.[86] The most common method involves the addition ofdiatomaceous earth to honey that is heated to 60 °C (140 °F) and passed through filter paper or canvas until a cake of diatomaceous earth builds up on the filter.[71]
Ultrasonicated honey has been processed byultrasonication, a nonthermal processing alternative for honey. When honey is exposed to ultrasonication, most of the yeast cells are destroyed. Those cells that survive sonication generally lose their ability to grow, which reduces the rate of honey fermentation substantially. Ultrasonication also eliminates existing crystals and inhibits further crystallization in honey. Ultrasonically aided liquefaction can work at substantially lower temperatures around 35 °C (95 °F) and can reduce liquefaction time to less than 30 seconds.[87]
Creamed honey, also called whipped honey, spun honey, churned honey, honey fondant, and, in the UK, set honey, has been processed to control crystallization. Creamed honey contains a large number of small crystals, which prevent the formation of larger crystals that can occur in unprocessed honey. The processing also produces a honey with a smooth, spreadable consistency.[88]
Dried honey has the moisture extracted from liquid honey to create completely solid, nonsticky granules. This process may or may not include the use of drying andanticaking agents.[89] Dried honey is used in baked goods,[89] and to garnish desserts.[90]
Comb honey is still in the honey bees' wax comb. It is traditionally collected using standard woodenframes inhoney supers. The frames are collected and the comb is cut out in chunks before packaging. As an alternative to this labor-intensive method, plastic rings or cartridges can be used that do not require manual cutting of the comb, and speed packaging. Comb honey harvested in the traditional manner is also referred to as "cut-comb honey".[78]: 13 [91]
Chunk honey is packed in wide-mouthed containers; it consists of one or more pieces of comb honey immersed in extracted liquid honey.[78]: 13
Honey decoctions are made from honey or honey byproducts which have been dissolved in water, then reduced (usually by means of boiling). Other ingredients may then be added. (For example,abbamele has added citrus.) The resulting product may be similar tomolasses.
Baker's honey is outside the normal specification for honey, due to a "foreign" taste or odor, or because it has begun to ferment or has been overheated. It is generally used as an ingredient in food processing. Additional requirements exist for labeling baker's honey, including that it may not be sold labeled simply as "honey".[92]
Countries have differing standards for grading honey.In the US, honey grading is performed voluntarily based uponUSDA standards. USDA offers inspection and grading "as on-line (in-plant) or lot inspection...upon application, on a fee-for-service basis." Honey is graded based upon a number of factors, including water content, flavor and aroma, absence of defects, and clarity. Honey is also classified by color, though it is not a factor in the grading scale.[93]
The USDA honey grade scale is:
Grade
Soluble solids
Flavor and aroma
Absence of defects
Clarity
A
≥ 81.4%
Good—"has a good, normal flavor and aroma for the predominant floral source or, when blended, a good flavor for the blend of floral sources and the honey is free from caramelized flavor or objectionable flavor caused by fermentation, smoke, chemicals, or other causes with the exception of the predominant floral source"
Practically free—"contains practically no defects that affect the appearance or edibility of the product"
Clear—"may contain air bubbles which do not materially affect the appearance of the product and may contain a trace of pollen grains or other finely divided particles of suspended material which do not affect the appearance of the product"
B
≥ 81.4%
Reasonably good—"has a reasonably good, normal flavor and aroma for the predominant floral source or, when blended, a reasonably good flavor for the blend of floral sources and the honey is practically free from caramelized flavor and is free from objectionable flavor caused by fermentation, smoke, chemicals, or other causes with the exception of the predominant floral source"
Reasonably free—"may contain defects which do not materially affect the appearance or edibility of the product"
Reasonably clear—"may contain air bubbles, pollen grains, or other finely divided particles of suspended material which do not materially affect the appearance of the product"
C
≥ 80.0%
Fairly good—"has a fairly good, normal flavor and aroma for the predominant floral source or, when blended, a fairly good flavor for the blend of floral sources and the honey is reasonably free from caramelized flavor and is free from objectionable flavor caused by fermentation, smoke, chemicals, or other causes with the exception of the predominant floral source"
Fairly free—"may contain defects which do not seriously affect the appearance or edibility of the product"
Fairly clear—"may contain air bubbles, pollen grains, or other finely divided particles of suspended material which do not seriously affect the appearance of the product"
Substandard
Fails Grade C
Fails Grade C
Fails Grade C
Fails Grade C
India certifies honey grades based on additional factors, such as the Fiehe's test, and other empirical measurements.[94]
Indicators of quality
High-quality honey can be distinguished by fragrance, taste, and consistency. Ripe, freshly collected, high-quality honey at 20 °C (68 °F) should flow from a knife in a straight stream, without breaking into separate drops.[95] After falling down, the honey should form a bead. The honey, when poured, should form small, temporary layers that disappear fairly quickly, indicating high viscosity. If not, it indicates honey with excessive water content of over 20%,[95] not suitable for long-term preservation.[96]
In jars, fresh honey should appear as a pure, consistent fluid, and should not set in layers. Within a few weeks to a few months of extraction, many varieties of honey crystallize into a cream-colored solid. Some varieties of honey, including tupelo, acacia, and sage, crystallize less regularly. Honey may be heated during bottling at temperatures of 40–49 °C (104–120 °F) to delay or inhibit crystallization. Overheating is indicated by change in enzyme levels, for instance,diastase activity, which can be determined with the Schade or thePhadebas methods. A fluffy film on the surface of the honey (like a white foam), or marble-colored or white-spotted crystallization on a container's sides, is formed by air bubbles trapped during the bottling process.
A 2008 Italian study determined thatnuclear magnetic resonance spectroscopy can be used to distinguish between different honey types, and can be used to pinpoint the area where it was produced. Researchers were able to identify differences in acacia and polyfloral honeys by the differing proportions of fructose and sucrose, as well as differing levels of aromaticamino acidsphenylalanine andtyrosine. This ability allows greater ease of selecting compatible stocks.[97]
One hundred grams of honey provides about 1,270 kJ (304 kcal) of energy with no significant amounts of essentialnutrients.[7] Composed of 17% water and 82%carbohydrates, honey has low content offat,dietary fiber, andprotein.
Sugar profile
A mixture of sugars and other carbohydrates, honey is mainlyfructose (about 38%) andglucose (about 32%),[5] with remaining sugars includingmaltose,sucrose, and othercomplex carbohydrates.[5] Itsglycemic index ranges from 31 to 78, depending on the variety.[100] The specific composition, color, aroma, and flavor of any batch of honey depend on the flowers foraged by bees that produced the honey.[10]
One 1980 study found that mixedfloral honey from several United States regions typically contains the following:[101]
This means that 55% of the combined fructose and glucose content was fructose and 45% was glucose, which enables comparison with the essentially identical result (average of 56% and 44%) in the study described below:
A 2013NMR spectroscopy study of 20 different honeys from Germany found that their sugar contents comprised:
Fructose: 28% to 41%
Glucose: 22% to 35%
The average ratio was 56% fructose to 44% glucose, but the ratios in the individual honeys ranged from a high of 64% fructose and 36% glucose (one type of flower honey; table 3 in reference) to a low of 50% fructose and 50% glucose (a different floral source). This NMR method was not able to quantify maltose,galactose, and the other minor sugars as compared to fructose and glucose.[102]
Honey is afolk treatment for burns and other skin injuries. Preliminary evidence suggests that it aids in the healing of partial thickness burns 4–5 days faster than other dressings, and moderate evidence suggests that post-operative infections treated with honey heal faster and with fewer adverse events than withantiseptic andgauze.[103] The evidence for the use of honey in various other wound treatments is of low quality, and firm conclusions cannot be drawn.[103][104] Evidence does not support the use of honey-based products for the treatment ofvenous stasis ulcers oringrown toenail.[105][106] Several medical-grade honey products have been approved by theUSFood and Drug Administration for use in treating minor wounds and burns.[107]
Antibiotic
Honey has long been used as atopical antibiotic by practitioners oftraditional andherbal medicine.[108][109] Honey's antibacterial effects were first demonstrated by the Dutch scientist Bernardus Adrianus van Ketel in 1892.[110][111] Since then, numerous studies have shown that honey has broad-spectrum antibacterial activity againstgram-positive andgram-negative bacteria, although potency varies widely between different honeys.[107][111][112][113] Due to the proliferation ofantibiotic-resistant bacteria in the last few decades, there has been renewed interest in researching the antibacterial properties of honey.[109] Components of honey under preliminary research for potential antibiotic use includemethylglyoxal,hydrogen peroxide, and royalisin (also called defensin-1).[114][115]
Cough
For chronic and acute coughs, aCochrane review found no strong evidence for or against the use of honey.[116][117] For treating children, the systematic review concluded with moderate to low evidence that honey helps more than no treatment,diphenhydramine, andplacebo at giving relief from coughing.[117] Honey does not appear to work better thandextromethorphan at relieving coughing in children.[117] Other reviews have also supported the use of honey for treating children.[118][119]
The UKMedicines and Healthcare products Regulatory Agency recommends avoiding givingover-the-counter cough andcommon cold medication to children under six, and suggests "a homemade remedy containing honey and lemon is likely to be just as useful and safer to take", but warns that honey should not be given to babies because of the risk of infantbotulism.[120] The World Health Organization recommends honey as a treatment for coughs and sore throats, including for children, stating that no reason exists to believe it is less effective than a commercial remedy.[121]
Other
The use of honey has been recommended as a temporary intervention for known or suspectedbutton cell battery ingestions to reduce the risk and severity of injury to theesophagus caused by the battery prior to its removal.[122][123][124]
Consumption is sometimes advocated as a treatment forseasonal allergies due topollen, but scientific evidence to support the claim is inconclusive.[125] Honey is generally considered ineffective for the treatment ofallergic conjunctivitis.[125][127]
The majority of calories in honey are from fructose. When consumed in addition to a normal diet, fructose causes significant weight gain, but when fructose was substituted for other carbohydrates of equal energy value there was no effect on body weight.[128]
Honey has a mild laxative effect which has been noted as being helpful in alleviating constipation and bloating.[129]
Health hazards
Honey is generally safe when taken in typical food amounts,[118][125] but it may have various, potentialadverse effects orinteractions in combination with excessive consumption, existingdisease conditions, ordrugs.[125] Included among these are mild reactions to high intake, such asanxiety,insomnia, orhyperactivity in about 10% of children, according to one study.[118] No symptoms of anxiety, insomnia, or hyperactivity were detected with honey consumption compared toplacebo, according to another study.[118] Honey consumption may interact adversely with existingallergies, highblood sugar levels (as indiabetes), oranticoagulants used to controlbleeding, among otherclinical conditions.[125]
People who have aweakened immune system may be at risk of bacterial or fungal infection from eating honey.[130]
Botulism
Infants can develop botulism after consuming honey contaminated withClostridium botulinum endospores.[131]
Infantile botulism shows geographical variation. In the UK, only six cases were reported between 1976 and 2006,[132] yet the US has much higher rates: 1.9 per 100,000 live births, 47.2% of which are in California.[133] While the risk honey poses to infant health is small, taking the risk is not recommended until after one year of age, and then giving honey is considered safe.[134]
Mad honey intoxication is a result of eating honey containinggrayanotoxins.[135] Honey produced from flowers ofrhododendrons,mountain laurels,sheep laurel, andazaleas may cause honey intoxication. Symptoms include dizziness, weakness, excessive perspiration, nausea, and vomiting. Less commonly, low blood pressure, shock, heart rhythm irregularities, and convulsions may occur, with rare cases resulting in death. According to the FDA, honey intoxication is more likely when using "natural" unprocessed honey from farmers who may have a small number of hives because commercial processing, which pools of honey from numerous sources, dilutes the toxins.[136]
Toxic honey may also result when bees are proximate totutu bushes (Coriaria arborea) and the vine hopper insect (Scolypopa australis). Both are found throughout New Zealand. Bees gather honeydew produced by the vine hopper insects feeding on the tutu plant. This introduces the poisontutin into honey.[137] Only a few areas in New Zealand (theCoromandel Peninsula, EasternBay of Plenty Region and theMarlborough Sounds) frequently produce toxic honey. Symptoms of tutin poisoning include vomiting, delirium, giddiness, increased excitability, stupor, coma, and violent convulsions.[138] To reduce the risk of tutin poisoning, humans should not eat honey taken from feral hives in the risk areas of New Zealand. Since December 2001, New Zealand beekeepers have been required to reduce the risk of producing toxic honey by closely monitoring tutu, vine hopper, and foraging conditions within 3 km (2 mi) of their apiary.[citation needed] Intoxication is rarely dangerous.[135]
Honey collection is an ancient activity,[11] long preceding the honey bee's domestication; this traditional practice is known ashoney hunting. AMesolithic rock painting in a cave inValencia, Spain, dating back at least 8,000 years, depicts two honey foragers collecting honey and honeycomb from a wild bees' nest. The figures are depicted carrying baskets or gourds, and using aladder or series of ropes to reach the nest.[11] Humans followed thegreater honeyguide bird to wild beehives;[140] this behavior may have evolved with early hominids.[141][142] The oldest known honey remains were found inGeorgia during the construction of theBaku–Tbilisi–Ceyhan pipeline: archaeologists found honey remains on the inner surface of clay vessels unearthed in an ancient tomb, dating back between 4,700 and 5,500 years.[143][144][145] In ancient Georgia, several types of honey were buried with a person for journeys into the afterlife, including linden, berry, and meadow-flower varieties.[146]
The first written records of beekeeping are fromancient Egypt[when?], where honey was used to sweeten cakes, biscuits, and other foods and as a base forunguents in Egyptianhieroglyphs. The dead were often buried in or with honey in Egypt,Mesopotamia and other regions. Bees were kept at temples to produce honey for temple offerings, mummification and other uses.[147]
Inancient Greece, honey was produced from theArchaic to theHellenistic periods. In 594 BCE,[148] beekeeping aroundAthens was so widespread thatSolon passed a law about it: "He who sets up hives of bees must put them 300 feet [90 metres] away from those already installed by another".[149][4] Greek archaeological excavations of pottery located ancient hives.[150] According toColumella, Greek beekeepers of the Hellenistic period did not hesitate to move their hives over rather long distances to maximize production, taking advantage of the different vegetative cycles in different regions.[150] The spiritual and supposed therapeutic use of honey inancient India was documented in both theVedas and theAyurveda texts.[139]
In theHebrew Bible, thePromised Land (Canaan, the Land of Israel) is described 16 times as "theland of milk and honey"[152] as a metaphor for its bounty. Of the 55 times the word "honey" appears in the Hebrew Bible, 16 are part of the expression "the land of milk and honey", and only twice is "honey" explicitly associated with bees, both being related to wild bees.[152] Modern biblical researchers long considered that the original Hebrew word used in the Bible, (דבש,devash), refers to thesweet syrup produced fromfigs ordates, because the domestication of the honey bee was completely undocumented through archaeology anywhere in theancient Near East (excluding Egypt) at the time associated with the earlier biblical narratives[152] (books ofExodus,Judges,Kings, etc.). In 2005, however, an apiary dating from the 10th century BC was found inTel Rehov, Israel that contained 100 hives, estimated to produce half a ton of honey annually.[153][152] This was, as of 2007, the only such finding made by archaeologists in the entire ancient Near East region, and it opens the possibility that biblical honey was indeed bee honey.[152]
InJudaism, honey symbolizes the sweetness of the New Year,Rosh Hashanah, and is traditionally eaten with apple slices.
In Jewish tradition, honey is a symbol for the new year,Rosh Hashanah. At the traditional meal for that holiday, apple slices are dipped in honey and eaten to bring a sweet new year. SomeRosh Hashanah greetings show honey and an apple, symbolizing the feast. In some congregations, small straws of honey are given out to usher in the new year.[154] Pure honey is consideredkosher (permitted to be eaten by religious Jews), though it is produced by a flying insect, a non-kosher creature; eating other products of non-kosher animals is forbidden.[155] It belongs among theparve (neutral) foods, containing neither meat nor dairy products and allowed to be eaten together with either.
Early Christians used honey as a symbol of spiritual perfection in christening ceremonies.[147]
In Islam, an entire chapter (Surah) in theQuran is calledan-Nahl (the Bees). According to his teachings (hadith),Muhammad strongly recommendedhoney for healing purposes.The Quran promotes honey as a nutritious and healthy food, saying:
And thy Lord taught the Bee to build its cells in hills, on trees, and in (men's) habitations; Then to eat of all the produce (of the earth), and find with skill the spacious paths of its Lord: there issues from within their bodies a drink of varying colours, wherein is healing for men: verily in this is a Sign for those who give thought.[156][157]
In Hinduism, honey (Madhu) is one of the five elixirs of life (Panchamrita). In temples, honey is poured over the deities in a ritual calledMadhuabhisheka. TheVedas and other ancient literature mention the use of honey as a great medicinal and health food.[158]
In Buddhism, honey plays an important role in the festival ofMadhu Purnima, celebrated in India and Bangladesh. The day commemoratesBuddha's making peace among his disciples by retreating into the wilderness. According to legend, while he was there amonkey brought him honey to eat. OnMadhu Purnima, Buddhists remember this act by giving honey tomonks. The monkey's gift is frequently depicted inBuddhist art.[158]
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