Honey/ˈhʌni/ is a sweet food made by bees using nectar from flowers. The variety produced by honey bees (the genusApis) is the one most commonly referred to, as it is the type of honey collected by most beekeepers and consumed by people. Honeys produced by other bees (bumblebees, stingless bees) and insects (honey wasps) have different properties, and they are not discussed in this article.
Honey bees transform nectar into honey by a process of regurgitation and evaporation. They store it as a primary food source in wax honeycombs inside the beehive.
Honey gets its sweetness from the monosaccharidesfructose and glucose, and has approximately the same relative sweetness as granulated sugar. It has attractive chemical properties for baking and a distinctive flavor that leads some people to prefer it over sugar and other sweeteners. Most microorganisms do not grow in honey because of its low water activity of 0.6. However, honey sometimes contains dormant endospores of the bacterium Clostridium botulinum, which can be dangerous to infants, as the endospores can transform into toxin-producing bacteria in infants' immature intestinal tracts, leading to illness and even death.
Honey has had a long history in human consumption, and is used in various foods and beverages as a sweetener and flavoring. It also has a role in religion and symbolism. Flavors of honey vary based on the nectar source, and various types and grades of honey are available. It has also been used in various medicinal traditions to treat ailments. The study of pollens and spores in raw honey (melissopalynology) can determine floral sources of honey. Bees carry an electrostatic charge whereby they attract other particles in addition to pollen, which become incorporated into their honey; the honey can be analysed by the techniques of melissopalynology in area environmental studies of radioactive particles, dust and particulate pollution.
Honey's natural sugars are dehydrated, which prevents fermentation, with added enzymes to modify and transform their chemical composition and pH. Invertases and digestive acids hydrolyze sucrose to give the monosaccharides glucose and fructose. The invertase is one of these enzymes synthesized by the body of the insect.
Honey bees transform saccharides into honey by a process of regurgitation, a number of times, until it is partially digested. The bees do the regurgitation and digestion as a group. After the last regurgitation, the aqueous solution is still high in water, so the process continues by evaporation of much of the water and enzymatic transformation.
Honey is produced by bees as a food source. To produce a single jar of honey, foraging honey bees have to travel the equivalent of three times around the world. In cold weather or when fresh food sources are scarce, bees use their stored honey as their source of energy. By contriving for bee swarms to nest in artificial hives, people have been able to semidomesticate the insects, and harvest excess honey. In the hive (or in a wild nest), there are three types of bees:
The worker bees raise larvae and collect the nectar that will become honey in the hive. Leaving the hive, they collect sugar-rich flower nectar and return.
In the hive, the bees use their "honey stomachs" to ingest and regurgitate the nectar a number of times until it is partially digested. Invertase synthesized by the bees and digestive acids hydrolyze sucrose to give the same mixture of glucose and fructose. The bees work together as a group with the regurgitation and digestion until the product reaches a desired quality. It is then stored in honeycomb cells. After the final regurgitation, the honeycomb is left unsealed. However, the nectar is still high in both water content and natural yeasts, which, unchecked, would cause the sugars in the nectar to ferment. The process continues as bees inside the hive fan their wings, creating a strong draft across the honeycomb, which enhances evaporation of much of the water from the nectar. This reduction in water content raises the sugar concentration and prevents fermentation. Ripe honey, as removed from the hive by a beekeeper, has a long shelf life, and will not ferment if properly sealed.
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 a supersaturated liquid, containing more sugar than the water can typically dissolve at ambient temperatures. At room temperature, honey is a supercooled liquid, in which the glucose will precipitate into solid granules. This forms a semisolid solution of precipitated glucose crystals in a solution of fructose and other ingredients.
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 a metastable state, meaning that it will not crystallize until a seed crystal is added, or, more often, it is in a "labile" state, being saturated with enough sugars to crystallize spontaneously. 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 as brassica honey, will crystallize almost immediately after harvesting, while honeys with a low percentage of glucose, such as chestnut or tupelo honey, do not crystallize. Some types of honey may produce very large but few crystals, while others will produce many small crystals.
Crystallization is also affected by water content, because a high percentage of water will inhibit crystallization, as will a high dextrin 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, the nucleation 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 and, thus, the original texture and flavor can be preserved indefinitely.
Since honey normally exists below its melting point, it is a supercooled liquid. At very low temperatures, honey will not freeze solid. Instead, as the temperatures become colder, the viscosity of honey increases. Like most viscous liquids, the honey will become thick and sluggish with decreasing temperature. At −20 °C (−4 °F), honey may appear or even feel solid, but it will continue to flow at very slow rates. Honey has a glass transition between −42 and −51 °C (−44 and −60 °F). Below this temperature, honey enters a glassy state and will become an amorphous solid (noncrystalline).
The viscosity of honey is affected greatly by both temperature and water content. The higher the humidity, the easier honey will flow. Above its melting point, however, water has little effect on viscosity. Aside from water content, the composition of honey also has little effect on viscosity, with the exception of a few types. At 25 °C (77 °F), honey with 14% humidity will generally have a viscosity of around 400 poise, while a honey containing 20% humidity will have a viscosity of around 20 poise. Viscosity increase due to temperature occurs very slowly at first. A honey containing 16% humidity, at 70 °C (158 °F), will have a viscosity of around 2 poise, while at 30 °C (86 °F), the viscosity will be around 70 poise. As cooling progresses, honey will become more viscous at an increasingly rapid rate, reaching 600 poise around 14 °C (57 °F). However, while honey is very viscous, it has rather low surface tension.
A few types of honey have unusual viscous properties. Honey from heather or manuka display thixotropic properties. These types of honey enter a gel-like state when motionless, but then liquify when stirred.
Electrical and optical properties
Since honey contains electrolytes, in the form of acids and minerals, it exhibits varying degrees of electrical conductivity. Measurements of the electrical conductivity are used to determine the quality of honey in terms of ash content.
The effect honey has on light is useful for determining the type and quality. Variations in the water content alter the refractive index of honey. Water content can easily be measured with a refractometer. Typically, the refractive index for honey will range from 1.504 at 13% humidity, to 1.474 at 25%. Honey also has an effect on polarized light, in that it will rotate the polarization plane. The fructose will give a negative rotation, while the glucose will give a positive one. The overall rotation can be used to measure the ratio of the mixture.
Hygroscopy and fermentation
Honey has the ability to absorb moisture directly from the air, a phenomenon called hygroscopy. The amount of water the honey will absorb 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 humidity rises much above 25%. Honey will tend to absorb more water in this manner than the individual sugars would allow on their own, which may be due to other ingredients it contains.
Fermentation of honey will usually occur after crystallization because, without the glucose, the liquid portion of the honey primarily consists of a concentrated mixture of the 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 often pasteurized, to kill any yeast, by heating it above 70 °C (158 °F).
Like all sugar compounds, honey will caramelize if heated sufficiently, becoming darker in color, and eventually burn. However, honey contains fructose, which caramelizes at lower temperatures than the glucose. 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 as catalysts, decreasing the caramelization temperature even more. 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 called melanoidins, during a Maillard reaction. The Maillard reaction will occur slowly at room temperature, taking from a few to several months to show visible darkening, but will speed-up dramatically with increasing temperatures. However, the reaction can also be slowed by storing the honey at colder temperatures.
Unlike many other liquids, honey has very poor thermal conductivity, taking a long time to reach thermal equilibrium. Melting crystallized honey can easily result in localized caramelization if the heat source is too hot, or if it is not evenly distributed. However, honey will take substantially longer to liquify when just above the melting point than it will at elevated temperatures. Melting 20 kilograms of crystallized honey, at 40 °C (104 °F), can take up to 24 hours, while 50 kilograms 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 possible for the shortest amount of time.
The average pH of honey is 3.9, but can range from 3.4 to 6.1. Honey contains many kinds of acids, both organic and amino. However, the different types and their amounts vary considerably, depending on the type of honey. These acids may be aromatic or aliphatic (non-aromatic). The aliphatic acids contribute greatly to the flavor of honey by interacting with the flavors of other ingredients. Gluconic acid, for instance, is a flavor enhancer.
Honey can contain up to 18 of the 20 amino acids. However, amino acid content is almost negligible in honey, accounting for only 0.05–0.1% of the composition. The main amino acid is proline. Amino acids are derived almost solely from the bodies of the bees.
Honey use and production has a long and varied history. In many cultures, honey has associations that go beyond its use as a food. Honey is frequently used as a talisman and symbol of sweetness.
Honey seeker depicted on 8000 year old cave painting. At Araña Caves in Spain.
Honey collection is an ancient activity. Humans apparently began hunting for honey at least 8,000 years ago, as evidenced by a cave painting in Valencia, Spain. The painting is a Mesolithic rock painting, showing two honey-hunters collecting honey and honeycomb from a wild bee nest. The figures are depicted carrying baskets or gourds, and using a ladder or series of ropes to reach the wild nest.
The Greater Honeyguide bird guides humans to wild bee hives and this behavior may have evolved with early hominids
So far, the oldest remains of honey have been found in Georgia. Archaeologists have found honey remains on the inner surface of clay vessels unearthed an ancient tomb, dating back to some 4,700–5,500 years ago. In ancient Georgia, honey was packed for people's journeys into the afterlife. And more than one type, too – along for the trip were linden, berry, and a meadow-flower variety.
In ancient Egypt, honey was used to sweeten cakes and biscuits, and was used in many other dishes. Ancient Egyptian and Middle Eastern peoples also used honey for embalming the dead. The fertility god of Egypt, Min, was offered honey.
The spiritual and therapeutic use of honey in ancient India is documented in both the Vedas and the Ayurveda texts, which were both composed at least 4,000 years ago.
The art of beekeeping in ancient China has existed since time immemorial and appears to be untraceable to its origin. In the book "Golden Rules of Business Success" written by Fan Li (or Tao Zhu Gong) during the Spring and Autumn Period, there are some parts mentioning the art of beekeeping and the importance of the quality of the wooden box for bee keeping that can affect the quality of its honey.
Some cultures believed honey had many practical health uses. It was used as an ointment for rashes and burns, and to help soothe sore throats when no other practices were available.
In Hinduism, honey (Madhu) is one of the five elixirs of immortality (Panchamrita). In temples, honey is poured over the deities in a ritual called Madhuabhisheka. The Vedas and other ancient literature mention the use of honey as a great medicinal and health food.
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. Some Rosh 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.
The Hebrew Bible contains many references to honey. In the Book of Judges, Samson found a swarm of bees and honey in the carcass of a lion (14:8). In Old Testament law, offerings were made in the temple to God. The Book of Leviticus says that “Every grain offering you bring to the Lord must be made without yeast, for you are not to burn any yeast or honey in a food offering presented to the Lord” (2:11). In the Books of Samuel Jonathan is forced into a confrontation with his father King Saul after eating honey in violation of a rash oath Saul made (14:24–47). The Book of Exodus famously describes the Promised Land as a "land flowing with milk and honey" (33:3). However, the claim has been advanced that the original Hebrew (דבש devash) actually refers to the sweet syrup produced from the juice of dates. Pure honey is considered kosher even though it is produced by a flying insect, a nonkosher creature; other products of nonkosher animals are not kosher.
In Buddhism, honey plays an important role in the festival of Madhu Purnima, celebrated in India and Bangladesh. The day commemorates Buddha's making peace among his disciples by retreating into the wilderness. The legend has it that while he was there, a monkey brought him honey to eat. On Madhu Purnima, Buddhists remember this act by giving honey to monks. The monkey's gift is frequently depicted in Buddhist art.
In the Christian New Testament, Matthew 3:4, John the Baptist is said to have lived for a long period of time in the wilderness on a diet consisting of locusts and wild honey.
In Islam, there is an entire Surah in the Qur'an called an-Nahl (the Bee). According to hadith, Prophet Muhammad strongly recommended honey for healing purposes. The Qur'an promotes honey as a nutritious and healthy food. Below is the English translation of those specific verses.
"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" [Al-Quran 16:68–69].
Honey is collected from wild bee colonies, or from domesticated beehives. Wild bee nests are sometimes located by following a honeyguide bird.
Collecting honey is typically achieved by using smoke from a bee smoker to pacify the bees; this causes the bees to attempt to save the resources of the hive from a possible forest fire, and makes them far less aggressive. The honeycomb is removed from the hive and the honey is extracted from that, often using a honey extractor. The honey is then filtered. In many cases the beekeeper will responsibly leave enough honey in the beehive for the colony to survive. If extra food is required to maintain the colony the beekeeper may provide the hive with unprocessed honey or a honey substitute such as sugar water (in the fall) or crystalline sugar (in the winter - a "candyboard") so that the hive does not starve.
As a food and in cooking
The main uses of honey are in cooking, baking, as a spread on bread, and as an addition to various beverages, such as tea, and as a sweetener in some commercial beverages. According to The National Honey Board (a USDA-overseen organization), "honey stipulates a pure product that does not allow for the addition of any other substance...this includes, but is not limited to, water or other sweeteners". Honey barbecue and honey mustard are common and popular sauce flavors.
As a fermentable
Honey is the main ingredient in the alcoholic beverage mead, which is also known as "honey wine" or "honey beer". Historically, the ferment for mead was honey's naturally occurring yeast. Honey is also used as an adjunct in some beers.
Honey wine, or mead, is typically (modern era) made with a honey and water mixture with a pack of yeast added for fermentation. Primary fermentation usually takes 40 days, after which the must needs to be racked into a secondary fermentation vessel and left to sit about 35–40 more days. If done properly, fermentation will be finished by this point (though if a sparkling mead is desired, fermentation can be restarted after bottling by the addition of a small amount of sugar), but most meads require aging for 6–9 months or more in order to be palatable.
Percentages are roughly approximated using US recommendations for adults. Source: USDA Nutrient Database
Honey is a mixture of sugars and other compounds. With respect to carbohydrates, honey is mainly fructose (about 38.5%) and glucose (about 31.0%), making it similar to the synthetically produced inverted sugar syrup, which is approximately 48% fructose, 47% glucose, and 5% sucrose. Honey's remaining carbohydrates include maltose, sucrose, and other complex carbohydrates. As with all nutritive sweeteners, honey is mostly sugars and contains only trace amounts of vitamins or minerals. Honey also contains tiny amounts of several compounds thought to function as antioxidants, including chrysin, pinobanksin, vitamin C, catalase, and pinocembrin.[vague] The specific composition of any batch of honey depends on the flowers available to the bees that produced the honey.
Honey has a density of about 1.36 kilograms per litre (36% denser than water).
Isotope ratio mass spectrometry can be used to detect addition of corn syrup and cane sugar by the carbon isotopic signature. Addition of sugars originating from corn or sugar cane (C4 plants, unlike the plants used by bees, and also sugar beet, which are predominantly C3 plants) skews the isotopic ratio of sugars present in honey, but does not influence the isotopic ratio of proteins; in an unadulterated honey, the carbon isotopic ratios of sugars and proteins should match. As low as 7% level of addition can be detected.
Honey is classified by its floral source, and there are also divisions according to the packaging and processing used. There are also regional honeys. Honey is also graded on its color and optical density by USDA standards, graded on a scale called the Pfund scale, which ranges from 0 for "water white" honey to more than 114 for "dark amber" honey.
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. The rheological & melissopalynological properties of honey can be used to identify the major plant nectar source used in its production.
Most commercially available honey is blended, meaning it is a mixture of two or more honeys differing in floral source, color, flavor, density or geographic origin.
Polyfloral honey, also known as wildflower honey, is derived from the nectar of many types of flowers.
The taste may vary from year to year, and the aroma and the flavor can be more or less intense, depending on which bloomings are prevalent.
Instead of taking nectar, bees can take honeydew, the sweet secretions of aphids or other plant sap-sucking insects. Honeydew honey is very dark brown in color, with a rich fragrance of stewed fruit or fig jam, and is not as sweet as nectar honeys.Germany's Black Forest is a well known source of honeydew-based honeys, as well as some regions in Bulgaria, Tara (mountain) in Serbia and Northern California in the United States. In Greece, pine honey (a type of honeydew honey) constitutes 60–65% of the annual honey production. Honeydew honey is popular in some areas, but in other areas beekeepers have difficulty selling the stronger flavored product.
The production of honeydew honey has some complications and dangers. The honey has a much larger proportion of indigestibles than light floral honeys, thus causing dysentery to the bees, resulting in the death of colonies in areas with cold winters. Good beekeeping management requires the removal of honeydew prior to winter in colder areas. Bees collecting this resource also have to be fed protein supplements, as honeydew lacks the protein-rich pollen accompaniment gathered from flowers.
Classification by packaging and processing
Generally, honey is bottled in its familiar liquid form. However, honey is sold in other forms, and can be subjected to a variety of processing methods.
A variety of honey flavors and container sizes and styles from the 2008 Texas State Fair
Crystallized honey is honey in which some of the glucose content has spontaneously crystallized from solution as the monohydrate. Also called "granulated honey" or "candied honey." Honey that has crystallized (or commercially purchased crystallized) can be returned to a liquid state by warming.
Pasteurized honey is honey that has been heated in a pasteurization process which requires temperatures of 161 °F (72 °C) 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 of hydroxymethylfurfural (HMF) and reduces enzyme (e.g. diastase) activity. Heat also affects appearance (darkens the natural honey color), taste, and fragrance.
Raw honey is honey 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). Raw honey contains some pollen and may contain small particles of wax. Some allergy sufferers try using raw, local honey to build up a tolerance to the pollen in the air. However, hay fever is typically caused by pollen in the air, which is mostly from trees, weeds, and grass, rather than flowers.
Strained honey has been passed through a mesh material to remove particulate material (pieces of wax, propolis, other defects) without removing pollen, minerals or enzymes.
Filtered honey is honey of any type that 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. The process typically heats honey to 150–170 °F (66–77 °C) to more easily pass through the filter. Filtered honey is very clear and will not crystallize as quickly, making it preferred by the supermarket trade.
Ultrasonicated honey has been processed by ultrasonication, a non-thermal 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 of approximately 95 °F (35 °C) and can reduce liquefaction time to less than 30 seconds.
Creamed honey, also called whipped honey, spun honey, churned honey, candied 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.
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 and anticaking agents. Dried honey is used in baked goods, and to garnish desserts.
Comb honey is honey still in the honeybees' wax comb. It traditionally is collected by using standard wooden frames in honey 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".:13 In India, honey is harvested from forests in bee's natural habitat. It is said that honey will be consumed by the bees on the new moon day, so it is cultivated the day before.
Chunk honey is packed in widemouth containers consisting of one or more pieces of comb honey immersed in extracted liquid honey.:13
Honey decoctions are made from honey or honey by-products 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 to molasses.
Sealed frame of honey
Because of its unique 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 decades and even centuries. 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, its hydrophilic properties will pull moisture into the honey, eventually diluting it to the point that fermentation can begin.
Regardless of preservation, honey may crystallize over time. The crystals can be dissolved by heating the honey.
In the US, honey grading is performed voluntarily (USDA does offer inspection and grading "as on-line (in-plant) or lot inspection...upon application, on a fee-for-service basis.") based upon USDA standards. 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. The honey grade scale is:
Flavor and aroma
Absence of defects
Good—has a good, normal flavor and aroma for the predominant floral source and is free from caramelization, smoke, fermentation, chemicals and other odor causes
Practically free—practically no defects that affect appearance or edibility
Clear—may contain air bubbles that do not materially affect the appearance; may contain a trace of pollen grains or other finely divided particles of suspended material that do not affect appearance
> 18.6% and < 20.0%
Reasonably good—practically free from caramelization; free from smoke, fermentation, chemicals, and other causes
Reasonably free—do not materially affect appearance or edibility
Reasonably clear—may contain air bubbles, pollen grains, or other finely divided particles of suspended material that do not materially affect appearance
Fairly good—reasonably free from caramelization; free from smoke, fermentation, chemicals, and other causes
Fairly free—do not seriously affect the appearance or edibility
Fairly clear—may contain air bubbles, pollen grains, or other finely divided particles of suspended material that do not seriously affect appearance
Fails Grade C
Fails Grade C
Fails Grade C
Other countries may have differing standards on the grading of honey. India, for example, certifies honey grades based on additional factors, such as the Fiehe's test, and other empirical measurements.
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. 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 excessive water content (over 20%) of the product. Honey with excessive water content is not suitable for long-term preservation.
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 the Phadebas methods. A fluffy film on the surface of the honey (like a white foam), or marble-colored or white-spotted crystallization on a containers sides, is formed by air bubbles trapped during the bottling process.
A 2008 Italian study determined nuclear 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 aromatic amino acidsphenylalanine and tyrosine. This ability allows greater ease of selecting compatible stocks.
Historically, honey has been used by humans both orally and topically to treat various ailments including gastric disturbances, ulcers, wounds, and burns. However, it is only recently that the mechanisms underlying the antiseptic and antibacterial properties of honey have come to be understood. Much scientific research has been performed, with emphasis of late on fighting infections in wounds. Antibacterial constituents and mechanisms identified include hydrogen peroxide (H2O2), methylglyoxal (MGO), bee defensin-1, the osmotic effect, and pH effects.
In Ayurveda, a 4000-year-old treatise on medicine originating from India, honey is considered to positively affect all three primitive material imbalances of the body. Charaka and Sushruta applied honey to dressings for sores. "Vaatalam guru sheetam cha raktapittakaphapaham| Sandhatru cchedanam ruksham kashayam madhuram madhu|| "It has sweetness with added astringent as end taste. It is heavy, dry and cold. Its effect on doshas (imbalances) is that it aggravates vata (air / moving forces), scrapes kapha (mucus / holding forces) and normalizes pitta (catabolic fire) and rakta (blood). It promotes the healing process."
Per traditional yoga practice, daily consumption of honey mixed with warm water is said to strengthen the circulatory system, and is therefore recommended. A honey and warm water mixture is also recommended by yoga practitioners for asthmatics.[dubious– discuss]
The 3rd century Greek philosopher Celsus used mixes of honey and bran to treat burns.
Some wound gels which contain antibacterial raw honey and have regulatory approval are now available to help treat drug-resistant strains of bacteria (MRSA). One New Zealand researcher says a particular type of honey (manuka honey) may be useful in treating MRSA infections.
As an antimicrobial agent honey is useful in treating a variety of ailments. Antibacterial properties of honey are the result of the low water activity causing osmosis, chelation of free iron, its slow release of hydrogen peroxide, high acidity, and the antibacterial activity of methylglyoxal.
Honey appears to be effective in killing drug-resistant biofilms which are implicated in chronic rhinosinusitis.
Honey has an osmotic effect. Honey is primarily a saturated mixture of two monosaccharides, with a low water activity; most of the water molecules are associated with the sugars and few remain available for microorganisms, so it is a poor environment for their growth. If water is mixed with honey, it loses its low water activity, and therefore no longer possesses this antimicrobial property.
Hydrogen peroxide is formed in a slow-release manner by the enzyme glucose oxidase present in honey. It becomes active only when honey is diluted, requires oxygen to be available for the reaction (thus it may not work under wound dressings, in wound cavities or in the gut), is active only when the acidity of honey is neutralized by body fluids, can be destroyed by the protein-digesting enzymes present in wound fluids, and is destroyed when honey is exposed to heat and light. Honey chelates and deactivates free iron, which would otherwise catalyze the formation of oxygen free radicals from hydrogen peroxide, leading to inflammation. Also, the antioxidant constituents in honey help clean up oxygen free radicals present.
When honey is used topically (as, for example, a wound dressing), hydrogen peroxide is produced by dilution of the honey with body fluids. As a result, hydrogen peroxide is released slowly and acts as an antibacterial.
Use for diabetic ulcers
Topical honey has been used successfully in a comprehensive treatment of diabetic ulcers when the patient cannot use topical antibiotics.
The pH of honey is commonly between 3.2 and 4.5. This relatively acidic pH level prevents the growth of many bacteria.
The nonperoxide antibiotic activity is due to methylglyoxal (MGO) and bee defensin-1. Most honeys contain very low levels of MGO, but manuka honey contains very high levels. The presence of the synergist in manuka honey more than doubles MGO antibacterial activity.
Antioxidants in honey have even been associated with reducing the damage done to the colon in colitis in a study involving administering honey enemas to rats. Such claims are consistent with its use in many traditions of folk medicine.
Use for sore throats and coughs
Honey has also been used for centuries as a treatment for sore throats and coughs, and according to a Cochrane review revised in 2012 it may be an effective soothing agent for coughs in children (although honey should never be given to children one year old or younger).
Other medical applications
Unfiltered, pasteurized honey is widely believed to alleviate allergies, though neither commercially filtered nor raw honey was shown to be more effective than placebo in a controlled study of 36 participants with ocular allergies. Nearly 1 in 3 of the volunteers dropped out of the study because they couldn't tolerate eating one tablespoon of honey every day due to the overly sweet taste. The official conclusion: "This study does not confirm the widely held belief that honey relieves the symptoms of allergic rhinoconjunctivitis." A more recent study has shown pollen collected by bees to exert an antiallergenic effect, mediated by an inhibition of IgE immunoglobulin binding to mast cells. This inhibited mast cell degranulation and thus reduced allergic reaction. The risk of experiencing anaphylaxis as an immune system reaction may outweigh any potential allergy relief.
A review in the Cochrane Library suggests honey could reduce the time it takes for a mild burn to heal—up to four days sooner in some cases. The review included 19 studies with 2,554 participants. Although the honey treatment healed mild burns faster than traditional dressings did, the author recommends viewing the findings with caution, since a single research centre performed all of the burn studies.
Because of the natural presence of botulinumendospores in honey, children under one year of age should not be given honey. The more-developed digestive system of older children and adults generally destroys the spores. Infants, however, can contract botulism from honey. Medical grade honey can be treated with gamma radiation to reduce the risk of botulinum spores being present. Gamma radiation evidently does not affect honey's antibacterial activity, whether or not the particular honey's antibacterial activity is dependent upon peroxide generation.
Infantile botulism shows geographical variation. In the UK, only six cases have been reported between 1976 and 2006, yet the U.S. has much higher rates: 1.9 per 100,000 live births, 47.2% of which are in California. While the risk honey poses to infant health is small, it is recommended not to take the risk.
Honey produced from flowers of oleanders, rhododendrons, mountain laurels, sheep laurel, and azaleas 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. Honey intoxication is more likely when using "natural" unprocessed honey and honey from farmers who may have a small number of hives. Commercial processing, with pooling of honey from numerous sources, is thought to dilute any toxins.
Toxic honey may also result when bees are proximate to tutu 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 poison tutin into honey. Only a few areas in New Zealand (Coromandel Peninsula, Eastern Bay of Plenty and the Marlborough Sound) frequently produce toxic honey. Symptoms of tutin poisoning include vomiting, delirium, giddiness, increased excitability, stupor, coma, and violent convulsions. 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 kilometres (1.9 mi) of their apiary.
Honey-producing and consuming countries
2005 Honey-producing countries
Top Five Natural Honey Producing Countries
(in metric tons)
Mexico is also an important producer of honey, providing more than 4% of the world's supply. Much of this (about one-third) comes from the Yucatán Peninsula. Honey production began there when the Apis mellifera and the A. mellifera ligustica were introduced there early in the 20th century. Most of Mexico's Yucatán producers are small, family operations who use original traditional techniques, moving hives to take advantage of the various tropical and subtropical flowers.
Honey is also one of the gourmet products of the French island of Corsica. Corsican honey is certified as to its origin (Appellation d'origine contrôlée) just as are French wines, like Champagne.
Honey consumption per capita per year exceeds one kilogram in some countries like Austria, Germany and Switzerland.
Gallery of honey harvesting
Smoking the hive
Using a blower to remove bees from honey prior to removal to honey house
A beekeeper removing frames from the hive
A capped honey super frame
Opening the cells: Uncapping
An uncapping fork
Uncapping the cells by hand using an uncapping knife
Extracting the honey
Filtering the honey
Pouring in pots
View Honey Al Jabal Alkhdar near the city of Bayda, Libya
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