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The scope of this ontology is to help provide traceability for beer by providing a databse of all know hop varities as well as their components and properties that add flavoring to the beer. This is so that brewers can be assured they know exactly what they are getting when selecting hops for a brew adn help manage their inventory. This will also help suppliers provide brewers with testing data and integration with the inventories of the brewers.
Hops are the flower seed cone of the Hop (Humulus lupulus) vine that are primarily used for adding flavoring, or bitterness, to beers. Hops thrive mostly in the Northern hemisphere but it is cultivated in Austrailia, New Zealand and South Africa as well. Hops can be either male or female, but only the females produce the seed cones used that is valued for brewing.
The Hops Ontology was created to help provide traceability for brewers and to help brewers find the best match for the beer they want to brew.
According to Ray Neve, it is unclear when the first usage of hops came to be, there is a 3000 year old Finnish oral sega, however it is unreliable since it likely has been alterated or having additions. The first written record of hops cultivation was in 736 AD (Linke and Rebl, 1950) that tells of Wendish prisoner who had a hops garden in German. The Wends were Slavs, and the Slavic term for 'hops' was 'hmelj', which has Finnish origins therefore potentially corroborating the Finnish saga.
There is also a list of goods from Bohemia to Hamburg where hops is listed that dates back to 1101. Hop cultivation declined in Czech countries during the Thirty Year War and clippings were brought to surrounding areas. In the 14th century hop cultivation spread to western Europe, which they were specialized locally as hopped beer as opposed to unhopped ale.
It wasn't until the 19th century that Germany became the leaders in hop production and beer brewing. Even now in the 21st century, beer brewing is still more of an art than a science. It is still unknown what oils cause which flavoring. Indeed the aroma and taste tests are almost entirely subjective.
The Hops Ontology is used to help with the traceability of hops to make choosing hops easier for brewers to achieve the flavors they desire in their beers. Since there is much in terms of flavenoids in varieties that are not well documented, not to mention the affect of terroir.
Therefore by providing proper documentation on the origins and testing done on the hops as well as the type of hop will help brewers make more informed choices on what hops to use for either a new brew or to maintain consistantancy in popular recipes. This also can help local hop yards increase their business by providing documentation and assurances of quality.
All of the known properties of hops are listed as well as decription (if available) of what flavor with which they are associated.
Alpha acids are a group of acidic compounds that isomerize (add flavor) during the boiling process of beer brewing. They are found in the resin of the hop, however they are not considered oils, even though they are found in the hop oil.
Similar to alpha acids, beta acids are also a group of acidic compounds found in the resin of the hops but are not oils, however beta acids isomerize (add flavor) over a longer period of time than the alpha acids, usually during the fermentation process of beer brewing.
Since there still many unknowns in the composition of the hop oils or even which compounds cause which flavors. Therefore the Hops Ontology lists all of the known compounds and known association with flavorings. Therefore if those compounds are listed, they can be documented and if they are listed as just "Other Oils" then the Hops Ontology can handle that as well.
This ontology provides a central place to have all the known information on hop compounds as well as provide documentation on what exactly those compounds are and the procedures for how the testing of the compounds were done.
Storability is different than Hop Storability Index (HSI) in the sense that storability is the percentage of alpha acids that remain unoxidezed after a fixed period of time (six months). The percentage associated with the Storability of a type of hop is given after a number of tests and is roughly what one would expect to see after after six months of storage.
The HSI comes from testing a hop that has been harvested (or any point in time). The result shows the percentage of alpha acids remaining after that specific point in time.
Percieved Aroma is a property that is hard to model since it is a subjective property. Therefore, several hops aroma profiles were gathered and the aromas that appeared the most were put in this ontology.
As hop research and analysis continues, it is the goal, one day, for this ontology to associate prominent oils with aromas so that aroma profiles could automatically be generated based on an analysis of the amount of acids and prominent oils.
When one sees hops that are grown in different countries, such as Magnum (US) vs Magnum (DE), are assumed to be genetically identical. The reason why there are multiple classes for hops that are the same (genetically) is due to terroir. This ontology shows that terroir has a large impact on hop aroma, which is why there are multiple classes for hops that are genetically identical.
The market has difficulty differentiating between variety name and brand name, the following is a list of sources that were used in this ontology.
This ontology tries to reference as many credible source as possible, however due to the highly subjective nature of hop aromas, some of the references that were used may not have been peer reviewed.
Dictionaries: AlphaAcids, BetaAcids, Hops,
Classes: AlphaAcids, BetaAcids, Cannabaceae, H-japonicus, H-yunnanensis, HSI, Hops, Humulus,
Properties: substitute,
Instances: Adhumulone, Adilupulone, Cohumulene, Colupulone, HopsAhtanum, HopsAmarillo, HopsApollo, HopsAramis, HopsBanner, HopsBelma, HopsBobek, HopsBravo, HopsBritishKentGoldings, HopsCalypso, HopsCascade, HopsCascadeUS, HopsCashmere, HopsCeleia, HopsCentennial, HopsChallenger, HopsChinook, HopsCitra, HopsCluster, HopsColumbia, HopsColumbus, HopsComet, HopsCrystal, HopsDana, HopsDelta, HopsElDorado, HopsEquinox, HopsEroica, HopsFalconersFlight, HopsFirstGold, HopsFuggle, HopsGalaxy, HopsGalena, HopsGlacier, HopsGolding, HopsGoldingUS, HopsGreenBullet, HopsHallertau, HopsHelga, HopsHerkules, HopsHersbrucker, HopsHorizon, HopsHuellMelon, HopsJester, HopsLiberty, HopsLusk, HopsMagnum, HopsMagnumUS, HopsMandarinaBavaria, HopsMeridian, HopsMerkur, HopsMillennium, HopsMittelfruh, HopsMosaic, HopsMotueka, HopsMountRinier, HopsMt.Hood, HopsNelsonSauvin, HopsNewport, HopsNorthernBrewer, HopsNugget, HopsOlympic, HopsPacificGem, HopsPacifica, HopsPerle, HopsPioneer, HopsPolaris, HopsPoncelet, HopsPrideofRingwood, HopsProgress, HopsSaaz, HopsSantiam, HopsSaphir, HopsSelect, HopsSimcoe, HopsSorachiAce, HopsStyrianGolding, HopsSummit, HopsTarget, HopsTeamaker, HopsTettnanger, HopsTradition, HopsTriplePearl, HopsUSDA21055, HopsUltra, HopsVanguard, HopsWaiiti, HopsWaimea, HopsWakatu, HopsWarrior, HopsWhitbreadGoldings, HopsWillamette, Humulene, Humulone, Lupulone, Rakau,
URI: https://rdf.ag/o/hops#AlphaAcids
None
Alpha acids are of great interest to beer brewers as they are agents that add bittering to the beer when they are isomerized (through the boiling process) to iso-humulons, or iso-alpha acids. Humulone, Cohumulone and adhumulone make up this class of acids. These acids are found in the resin, lupulin, of the hop cone. These chemicals are hexagonal molecules that when non-isomerized are insoluble in aqueous solutions. They are usually expressed in terms of a percentage of the hop's total weight. It remains unclear as to which of the humulones creates the cleanest bitterness in beers, however it is agreed upon that the higher the alpha acid content, the harsher the bitterness in the finished beer.
Concepts: Adhumulone, Cohumulene, Humulene, Humulone,
URI: https://rdf.ag/o/hops#BetaAcids
None
Beta acids, like alpha acids, are found in hop resin. Although only trace amounts survive the brewing process, the ratio of alpha to beta acids are very important to brewers as that ratio determines the decline of the bitterness of hops in storage. When beta acids oxidize, one of compounds that emerges is cohulupulone, which comes from colupulone, does provide some bittering to beer flavor. Once hulupulones are formed, they are relatively stable and can survive the brewing process. Therefore, as alpha acids degrade when they are oxidized during the storage process, bitterness can be recovered as hulupulones formed from oxidation, which is why the alpha to beta acid ratio is so important.
Concepts: Adilupulone, Colupulone, Lupulone,
URI: https://rdf.ag/o/hops#Hops
None
H. lupulus has the most value of this genus as the flowers or 'hops' are a key ingredient in beer. This species is mostly grown in the Northern Hemisphere (between 35˚ and 55˚N) but it is also cultivated in Australia, New Zealand and South Africa.
Concepts: HopsAhtanum, HopsAmarillo, HopsApollo, HopsAramis, HopsBanner, HopsBelma, HopsBobek, HopsBravo, HopsBritishKentGoldings, HopsCalypso, HopsCascade, HopsCascadeUS, HopsCashmere, HopsCeleia, HopsCentennial, HopsChallenger, HopsChinook, HopsCitra, HopsCluster, HopsColumbia, HopsColumbus, HopsComet, HopsCrystal, HopsDana, HopsDelta, HopsElDorado, HopsEquinox, HopsEroica, HopsFalconersFlight, HopsFirstGold, HopsFuggle, HopsGalaxy, HopsGalena, HopsGlacier, HopsGolding, HopsGoldingUS, HopsGreenBullet, HopsHallertau, HopsHelga, HopsHerkules, HopsHersbrucker, HopsHorizon, HopsHuellMelon, HopsJester, HopsLiberty, HopsLusk, HopsMagnum, HopsMagnumUS, HopsMandarinaBavaria, HopsMeridian, HopsMerkur, HopsMillennium, HopsMittelfruh, HopsMosaic, HopsMotueka, HopsMountRinier, HopsMt.Hood, HopsNelsonSauvin, HopsNewport, HopsNorthernBrewer, HopsNugget, HopsOlympic, HopsPacificGem, HopsPacifica, HopsPerle, HopsPioneer, HopsPolaris, HopsPoncelet, HopsPrideofRingwood, HopsProgress, HopsSaaz, HopsSantiam, HopsSaphir, HopsSelect, HopsSimcoe, HopsSorachiAce, HopsStyrianGolding, HopsSummit, HopsTarget, HopsTeamaker, HopsTettnanger, HopsTradition, HopsTriplePearl, HopsUSDA21055, HopsUltra, HopsVanguard, HopsWaiiti, HopsWaimea, HopsWakatu, HopsWarrior, HopsWhitbreadGoldings, HopsWillamette, Rakau,
URI: https://rdf.ag/o/hops#AlphaAcids
None
Alpha acids are of great interest to beer brewers as they are agents that add bittering to the beer when they are isomerized (through the boiling process) to iso-humulons, or iso-alpha acids. Humulone, Cohumulone and adhumulone make up this class of acids. These acids are found in the resin, lupulin, of the hop cone. These chemicals are hexagonal molecules that when non-isomerized are insoluble in aqueous solutions. They are usually expressed in terms of a percentage of the hop's total weight. It remains unclear as to which of the humulones creates the cleanest bitterness in beers, however it is agreed upon that the higher the alpha acid content, the harsher the bitterness in the finished beer.
URI: https://rdf.ag/o/hops#BetaAcids
None
Beta acids, like alpha acids, are found in hop resin. Although only trace amounts survive the brewing process, the ratio of alpha to beta acids are very important to brewers as that ratio determines the decline of the bitterness of hops in storage. When beta acids oxidize, one of compounds that emerges is cohulupulone, which comes from colupulone, does provide some bittering to beer flavor. Once hulupulones are formed, they are relatively stable and can survive the brewing process. Therefore, as alpha acids degrade when they are oxidized during the storage process, bitterness can be recovered as hulupulones formed from oxidation, which is why the alpha to beta acid ratio is so important.
URI: https://rdf.ag/o/hops#Cannabaceae
Hemp Family
There are the only two genera of this family are Humulus and Canabus. Mainly grown in the temperate climates of the Northern Hemisphere, the members of this family can be characterize by having palmately lobed or compound leaves that are borne in spirals or oppositely. Individuals are doiecious (one is either male or female) and petalless, bearing a single seeded fruit that is dry, either achenes or samaras.
URI: https://rdf.ag/o/hops#H-japonicus
None
H. japanicus is native to Japan and China, however since this species does not have the lupulin glands it is not viable for brewing.
URI: https://rdf.ag/o/hops#H-yunnanensis
None
H. yunnanensis is found in Southern China and not much else is known about this species.
URI: https://rdf.ag/o/hops#HSI
HSI
HSI is the measurement of the degredation of alpha and beta acids during hop storage and handling. This is useful to brewers as a way to asses the freshness of hops. Through the use of spectrophotometric analysis of the hops the amount of oxidation compounds (absorb light near 275nm) is divided by acids (absorbes light at 325nm) the resulting ratio is the HSI. If the HSI is less than 0.30 it indicates good quality, 0.30 - 0.40 is acceptable quality, and an HSI greater than 0.40 indicates questionable quality. Harvest timing, oxygen, temperature and storage duration are all factors that impact HSI. When properly stored and handled, HSI can remain stable even after a year.
URI: https://rdf.ag/o/hops#Hops
None
H. lupulus has the most value of this genus as the flowers or 'hops' are a key ingredient in beer. This species is mostly grown in the Northern Hemisphere (between 35˚ and 55˚N) but it is also cultivated in Australia, New Zealand and South Africa.
URI: https://rdf.ag/o/hops#Humulus
None
The genus Humulus is a cousin of the genus Cannabis, both of the family Cannabaceae. The genus Humulus comprises of three species: H. lupulus, H. japonicus and H. yunnanensis.
URI: https://rdf.ag/o/hops#substitute
Substitute
A hop (or hops) that is similar in aromatic profile to be substituted for another in a beer brew.
URI: https://rdf.ag/o/hops#HopsBritishKentGoldings
British Kent Goldings
URI: https://rdf.ag/o/hops#HopsCascadeUS
Cascade (US)
Cascade is one of the most widely cultivated US hop variety, named after the Cascades mountain range, with an aroma profile of citrus, grapefruit, floral and spicy notes. Noteable characteristics are long, dark green cones and a low alpha acid content relative to other hops. Cascade was released for cultivation in 1972 by a USDA breeding program in Corvallis, Oregon. It has a predigree of [Fuggle x (Serebrianka-Fuggle Seedling)] x OP.
URI: https://rdf.ag/o/hops#HopsCashmere
Cashmere
Cashmere is a result of the cross between Cascade and Northern Brewer, released by Washington State UNiversity in 2013. It is said to be a good dual-purpose hop for bittering and aroma.
URI: https://rdf.ag/o/hops#HopsCentennial
Centennial
Sometimes referred to as 'Super Cascade', this hop is known as a dual-purpose hop for it's aroma and bittering affect in brews. Its popularity has been increasing among craft brewers. Formerly known as Hop W415-90, that was hybridized in 1974 at the Irrigated Agriculture Research and Extension Center. This hop was renamed 'Centennial' for the 100th anniversary of Washington's statehood in 1989. It was grown experimentally for a few years, which is why the USDA assigned its assession number 1987, when it got the name Centennial in 1989. PEDIGREE: OR6619-04 x 63015M; (Brewer's Gold2 x Fuggle-Fuggle Seedling) x (Brewer's Gold2 x East Kent Golding - Bavarian Seedling)Brew/Gold; 3/32 Fuggle; 1/16 East Kent Golding; 1/32 Bavarian; 1/16 unknown
URI: https://rdf.ag/o/hops#HopsChinook
Chinook
Chinook, formerly W415-90, is a hop that came about from the cross between Petham Golding x Brewer's Gold - Utah 526-4 68052 x 63012M through a USDA breeding program in Washington state in 1985. It has grown in popularity among craft brewers but is also highly respected among larger breweries for it's high alpha acid content and notes of citrus and pine.
URI: https://rdf.ag/o/hops#HopsElDorado
El Dorado
1- El Dorado is an American hops created by CLS Farms, LLC in 2008 and released to the public in 2010. This hop is good for bittering and for adding aroma due to its high alpha acid and oil content.
2- El Dorado est un houblon américain créé par CLS Farms, LLC en 2008 et rendu public en 2010. Ce houblon est bon pour l'amertume et pour l'ajout d'arôme en raison de sa forte teneur en acide alpha et en huile.
URI: https://rdf.ag/o/hops#HopsFalconersFlight
Falconer's Flight
URI: https://rdf.ag/o/hops#HopsGoldingUS
Golding (US)
Golding comes from the group of cultivars grown in East Kent, United Kingdom. US Golding are typically derived from Canterbury (villiage in East Kent) Golding hops. This hop was originally grown in British Columbia, Canada and it was then appearing in Washington and Oregon states in 1993. Golding is known for its delicate, sweet and floral notes.
URI: https://rdf.ag/o/hops#HopsMagnumUS
Magnum (US)
Magnum, or Hallertauer Magnum, is a German hops cultivar. While genetically identical, Magnum that is grown in the US will have different characteristics due to the terroir and environmental differences in the US. It was recieved by the USDA in 1992. It is well known as a bittering hop due to its high alpha and cohumulone content. PEDIGREE: Galena (USDA 21182) x German male hop Nr. 75/5/3.
URI: https://rdf.ag/o/hops#HopsMandarinaBavaria
Mandarina Bavaria
URI: https://rdf.ag/o/hops#HopsNewport
Newport
Newport is a bittering hop with high alpha and beta acid content, developed by the USDA-ARS and recieving its accession number in 2000. This hop is the result of the cross between Hallertauer 'Magnum' and USDA 58111M as a new multiple disease-resistant bittering hop.
URI: https://rdf.ag/o/hops#HopsNugget
Nugget
Nugget is a bittering hop known for its high alpha content while having a low beta and cohumolone content. Therefore, this hop is a suitable hop to add bitter base to ales. It was bred in 1970 in Corvallis, Oregon (then called 7005-194); its accession number was assigned in 1978. PEDIGREE: USDA 65009 x 63015M; 5/8 Brewer's Gold, 1/8 Early Green, 1/16 East Kent Golding, 1/32 Bavarian, 5/32 Unknown.
URI: https://rdf.ag/o/hops#HopsPrideofRingwood
Pride of Ringwood
URI: https://rdf.ag/o/hops#HopsSorachiAce
Sorachi Ace
Sorachi Ace was developed by Dr. Mori sor Sapporo Breweries Co. Ltd in Japan 1984; a cross between Brewer's Gold, Saaz and Beikei No. 2 male. An aromatic hop that is popular among craft brewers. PEDIGREE: (Brewer's Gold x Saazer -OP) x Beikei No. 2 male; Note: The female parent is the Japanese seedling 70K-SH6 (USDA 21233) which was develioped by Dr. Mori sor Sapporo Breweries Co. Ltd.
URI: https://rdf.ag/o/hops#HopsTriplePearl
TriplePearl
TriplePearl was developped by the USDA-ARS as a seedless, more virus-resistant variety of 'Perle'. The USDA-ARS Research Project #425226 succeeded in creating a triploid (sterile) hop in 2013.
URI: https://rdf.ag/o/hops#HopsWhitbreadGoldings
Whitbread Goldings
URI: https://rdf.ag/o/hops#HopsWillamette
Willamette
Willamette is one of the most popular hop cultivars grown in the US. It was named after Willamette River that runs though Oregon, where it was developped by the USDA breeding program and released in 1976. It is characterized by having a low alpha acid content. PEDIGREE: Tetraploid Fuggle (USDA 21003) x Fuggle seedling 2-4.
Version 1.2
Version 1.1
Deprecated Terms:
This bibliography is available as a Bibtex file here.
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