Agar: Difference between revisions

Latest revision as of 23:16, 25 May 2026

Green tea-flavored yōkan, a popular Japanese red bean jelly made from agar

A blood agar plate used to culture bacteria and diagnose infection

Agar (/ˈeɪɡɑːr/ or /ˈɑːɡər/), or agar-agar, is a jelly-like substance consisting of polysaccharides obtained from the cell walls of some species of red algae (phylum Rhodophyta) primarily from the Gracilaria genus (Irish moss, ogonori) and the Gelidiaceae family (tengusa).^[1]^[2] These algae are known as agarophytes.^[3]^[4]

As found in nature, agar is a mixture of two components, the linear polysaccharide agarose and a heterogeneous mixture of smaller molecules called agaropectin.^[5] It forms the supporting structure in the cell walls of certain species of algae, and is released on boiling. The processing of food-grade agar removes the agaropectin, and the commercial product is essentially pure agarose.

Agar has been used as an ingredient in desserts throughout Asia and also as a solid substrate to contain culture media for microbiological work. Agar can be used as a laxative; an appetite suppressant; a vegan substitute for gelatin; a thickener for soups; in fruit preserves, ice cream, and other desserts; as a clarifying agent in brewing; and for sizing paper and fabrics.^[6]^[7]

Etymology

The word agar comes from agar-agar, the Malay name for red algae (Gigartina, Eucheuma,^[8] Gracilaria) from which the jelly is produced.^[9]^[10] It is also known as kanten (Script error: The function "langx" does not exist.) (from the phrase kan-zarashi tokoroten (寒晒し心太) or "cold-exposed agar"), Japanese isinglass, China grass, Ceylon moss, and Jaffna moss.^[11] Gracilaria edulis or its synonym G. lichenoides is specifically referred to as agal-agal or Ceylon agar.^[12]

History

File:Ogo.jpg

Ogonori, the most common red algae used to make agar

Macroalgae have been used widely as food by coastal cultures, especially in Southeast Asia.^[13]^[14] In the Philippines, Gracilaria, known as gulaman (also guraman, gar-garao, or gulaman dagat, among other names) in Tagalog, have been harvested and used as food for centuries, eaten both fresh or sun-dried and turned into jellies. The earliest historical attestation is from the Vocabulario de la lengua tagala (1754) by the Jesuit priests Juan de Noceda and Pedro de Sanlucar, where golaman or gulaman was defined as "una yerva, de que se haze conserva a modo de Halea, naze en la mar" ("a herb, from which a jam-like preserve is made, grows in the sea"), with an additional entry for guinolaman to refer to food made with the jelly.^[15]^[16]^[14]

Carrageenan, derived from gusô (Eucheuma spp.), which also congeals into a gel-like texture is also used similarly among the Visayan peoples and have been recorded in the even earlier Diccionario De La Lengua Bisaya, Hiligueina y Haraia de la isla de Panay y Sugbu y para las demas islas (c. 1637) of the Augustinian missionary Alonso de Méntrida (in Spanish). In the book, Méntrida describes gusô as being cooked until it melts, and then allowed to congeal into a sour dish.^[17]

In Ambon Island in the Maluku Islands of Indonesia, agar is extracted from Graciliaria and eaten as a type of pickle or a sauce.^[14] Jelly seaweeds were also favoured and foraged by Malay communities living on the coasts of the Riau Archipelago and Singapore in Southeast Asia for centuries. 19th century records indicate that dried Graciliaria were one of the bulk exports of British Malaya to China. Poultices made from agar were also used for swollen knee joints and sores in Johore and Singapore.^[14]^[18]

The application of agar as a food additive in Japan is alleged to have been discovered in 1658 by Mino Tarōzaemon (美濃太郎左衞門), an innkeeper in current Fushimi-ku, Kyoto, who, according to legend, was said to have discarded surplus seaweed soup (Tokoroten) and noticed that it gelled later after a winter night's freezing.^[19] Agar normally solidifies at room temperature without the need to freeze.^[20]

Agar was first subjected to chemical analysis in 1859 by the French chemist Anselme Payen, who had obtained agar from the marine algae Gelidium corneum.^[21]

Beginning in the late 19th century, agar began to be used as a solid medium for growing various microbes. Agar was first described for use in microbiology in 1882 by the German microbiologist Walther Hesse, an assistant working in Robert Koch's laboratory, on the suggestion of his wife Fanny Hesse.^[22]^[23] Agar quickly supplanted gelatin as the base of microbiological media, due to its higher melting temperature, allowing microbes to be grown at higher temperatures without the media liquefying.^[24]

With its newfound use in microbiology, agar production quickly increased. This production centered on Japan, which produced most of the world's agar until World War II.^[25] However, with the outbreak of World War II, many nations were forced to establish domestic agar industries in order to continue microbiological research.^[25] Around the time of World War II, approximately 2,500 tons of agar were produced annually.^[25] By the mid-1970s, production worldwide had increased dramatically to approximately 10,000 tons each year.^[25] Since then, production of agar has fluctuated due to unstable and sometimes over-utilized seaweed populations.^[26]

Chemical composition

File:Agarose polymere.svg

The structure of an agarose polymer

Agar consists of a mixture of two polysaccharides: agarose and agaropectin. Agarose constitutes about 70% of the mixture, while agaropectin constitutes about 30% of it.^[27] Agarose is a linear polymer made up of repeating units of agarobiose, a disaccharide made up of D-galactose and 3,6-anhydro-L-galactopyranose.^[28] Agaropectin is a heterogeneous mixture of smaller molecules that occur in lesser amounts, and is made up of alternating units of D-galactose and L-galactose heavily modified with acidic side-groups, such as sulfate, glucuronate, and pyruvate.^[29]^[27]^[28]

Physical properties

Agar exhibits a phenomenon known as hysteresis whereby, when mixed with water, it solidifies and forms a gel below about 32–42 °C (305–315 K; 90–108 °F), which is called the gel point, and melts above 85 °C (358 K; 185 °F), which is the melting point.^[30] Hysteresis is the property of having a difference between the gel point and melting point temperatures.^[31] This property lends a suitable balance between easy melting and good gel stability at relatively high temperatures.^[32] Since many scientific applications require incubation at temperatures close to human body temperature (37 °C), agar is more appropriate than other solidifying agents that melt at this temperature, such as gelatin.^[33]

Uses

Culinary

File:Sago Gulaman.jpg

Sago at gulaman in Filipino cuisine is made from agar (gulaman), pearl sago, and sugar syrup flavored with pandan.

Agar-agar is a natural vegetable gelatin counterpart.^[34]^[35] It is white and semi-translucent when sold in packages as washed and dried strips or in powdered form.^[34]^[36] It can be used to make jellies,^[37] puddings, and custards.^[38] When making jelly, it is boiled in water until the solids dissolve. Sweetener, flavoring, coloring, fruits and or vegetables are then added, and the liquid is poured into molds to be served as desserts and vegetable aspics or incorporated with other desserts such as a layer of jelly in a cake.^[36]

Agar-agar is approximately 80% dietary fiber, so it can serve as an intestinal regulator.^[39] Its bulking quality has been behind fad diets in Asia, for example the kanten (the Japanese word for agar-agar^[4]) diet. Once ingested, kanten triples in size and absorbs water. This results in the consumers feeling fuller.

Asian culinary

One use of agar in Japanese cuisine is in anmitsu, a dessert made of small cubes of agar jelly and served in a bowl with various fruits or other ingredients.^{[citation needed]} It is also the main ingredient in mizu yōkan, another popular Japanese food.^{[citation needed]} In Philippine cuisine, it is used to make the jelly bars in the various gulaman refreshments like sago't gulaman, samalamig, or desserts such as buko pandan, agar flan, halo-halo, fruit cocktail jelly, and the black and red gulaman used in various fruit salads.^{[citation needed]} In Vietnamese cuisine, jellies made of flavored layers of agar-agar, called thạch, are a popular dessert, and are often made in ornate molds for special occasions.^{[citation needed]} In Indian cuisine, agar is used for making desserts.^{[citation needed]} In Burmese cuisine, a sweet jelly known as kyauk kyaw is made from agar.^{[citation needed]} Agar jelly is widely used in Taiwanese bubble tea.^{[citation needed]}

Other culinary

File:00114jfCuisine of Bulacan Food Cakes Delicaciesfvf 30.jpg

Crema de fruta, a traditional Filipino fruitcake, is made with an agar layer on top to keep the fruit components in place.

It can be used as addition to (or as a replacement for) pectin in jelly, jam, or marmalade, as a substitute to gelatin for its superior gelling properties, and as a strengthening ingredient in souffles and custards. Another use of agar-agar is in a Russian dish ptich'ye moloko (bird's milk), a rich jellified custard (or soft meringue) used as a cake filling or chocolate-glazed as individual sweets.

Agar-agar may also be used as the gelling agent in gel clarification, a culinary technique used to clarify stocks, sauces, and other liquids. Mexico has traditional candies made out of Agar gelatin, most of them in colorful, half-circle shapes that resemble a melon or watermelon fruit slice, and commonly covered with sugar. They are known in Spanish as Dulce de Agar (Agar sweets)

Agar-agar is an allowed nonorganic/nonsynthetic additive used as a thickener, gelling agent, texturizer, moisturizer, emulsifier, flavor enhancer, and absorbent in certified organic foods.^[40]

Microbiology

Agar plate

File:Agar Plate.jpg

100 mm (3.9 in) diameter Petri dishes containing agar gel for bacterial culture

An agar plate or Petri dish is used to provide a growth medium using a mix of agar and other nutrients in which microorganisms, including bacteria and fungi, can be cultured and observed under the microscope. Agar is indigestible for many organisms so that microbial growth does not affect the gel used and it remains stable. Agar is typically sold commercially as a powder that can be mixed with water and prepared similarly to gelatin before use as a growth medium. Nutrients are typically added to meet the nutritional needs of the microbes organism, the formulations of which may be "undefined" where the precise composition is unknown, or "defined" where the exact chemical composition is known. Agar is often dispensed using a sterile media dispenser.

Different algae produce various types of agar. Each agar has unique properties that suit different purposes. Because of the agarose component, the agar solidifies. When heated, agarose has the potential to melt and then solidify. Because of this property, they are referred to as "physical gels". In contrast, polyacrylamide polymerization is an irreversible process, and the resulting products are known as chemical gels.

There are a variety of different types of agar that support the growth of different microorganisms. A nutrient agar may be permissive, allowing for the cultivation of any non-fastidious microorganisms; a commonly used nutrient agar for bacteria is the Luria Bertani (LB) agar which contains lysogeny broth, a nutrient-rich medium used for bacterial growth.^[41] Additionally, 2216 Marine Broth (MB) agar, with high salt content, is optimized for growing heterotrophic marine bacteria like those of the Vibrio genus, while Terrific Broth (TB) agar is used to non-selectively culture high yields of the bacterium E. coli. More generally, enriched media is an agar variety that is infused with the necessary nutrients required by fastidious organisms to grow. Despite the large diversity of agar mediums, yeast extract is a common ingredient across all varieties as it is a macronutrient that provides a nitrogen source for all bacterial cell types.

File:Lactose fementing (LF), and non-lactose fermenting (NLF) colonies on MacConkey agar.jpg

Other fastidious organisms may require the addition of different biological fluids such as horse or sheep blood, serum, egg yolk, and so on.^[42] Agar plates can also be selective, and can be used to promote the growth of bacteria of interest while inhibiting others. A variety of chemicals may be added to create an environment favourable for specific types of bacteria or bacteria with certain properties, but not conducive for growth of others. For example, antibiotics may be added in cloning experiments whereby bacteria with antibiotic-resistant plasmid are selected.^[43] In addition to antibiotic treated agar, other selective and indicator agar plates include TCBS agar and MacConkey agar. Thiosulfate citrate bile salts sucrose (TCBS) agar is used to differentiate Vibrio species based on their sucrose metabolism, since only some will metabolize the sucrose in the plate and change its pH. Indicator dyes included in the gel will display a visual change of the pH by changing the gel color from green to yellow. MacConkey agar contains bile salts and crystal violet to selectively grow gram-negative bacteria and differentiate between species using pH-indicator dyes that demonstrate lactose metabolism properties.

File:Microorganisms-11-01566-g008.webp

Motility assays

As a gel, an agar or agarose medium is porous and therefore can be used to measure microorganism motility and mobility. The gel's porosity is directly related to the concentration of agarose in the medium, so various levels of effective viscosity (from the cell's "point of view") can be selected, depending on the experimental objectives.

A common identification assay involves culturing a sample of the organism deep within a block of nutrient agar. Cells will attempt to grow within the gel structure. Motile species will be able to migrate, albeit slowly, throughout the gel, and infiltration rates can then be visualized, whereas non-motile species will show growth only along the now-empty path introduced by the invasive initial sample deposition.

Another setup commonly used for measuring chemotaxis and chemokinesis utilizes the under-agarose cell migration assay, whereby a layer of agarose gel is placed between a cell population and a chemoattractant. As a concentration gradient develops from the diffusion of the chemoattractant into the gel, various cell populations requiring different stimulation levels to migrate can then be visualized over time using microphotography as they tunnel upward through the gel against gravity along the gradient.

Plant biology

File:Physcomitrella growing on agar plates.jpg

Physcomitrella patens plants growing axenically in vitro on agar plates. Petri dish is 9 cm (3.5 in) in diameter.

Research grade agar is used extensively in plant biology as it is optionally supplemented with a nutrient and/or vitamin mixture that allows for seedling germination in Petri dishes under sterile conditions (given that the seeds are sterilized as well). Nutrient and/or vitamin supplementation for Arabidopsis thaliana is standard across most experimental conditions. Murashige & Skoog (MS) nutrient mix and Gamborg's B₅ vitamin mix in general are used. A 1.0% agar/0.44% MS+vitamin dH₂O solution is suitable for growth media between normal growth temps.

When using agar, within any growth medium, it is important to know that the solidification of the agar is pH-dependent. The optimal range for solidification is between 5.4 and 5.7.^[44] Usually, the application of potassium hydroxide is needed to increase the pH to this range. A general guideline is about 600 μl 0.1M KOH per 250 ml GM. This entire mixture can be sterilized using the liquid cycle of an autoclave.

This medium nicely lends itself to the application of specific concentrations of phytohormones etc. to induce specific growth patterns in that one can easily prepare a solution containing the desired amount of hormone, add it to the known volume of GM, and autoclave to both sterilize and evaporate off any solvent that may have been used to dissolve the often-polar hormones. This hormone/GM solution can be spread across the surface of Petri dishes sown with germinated and/or etiolated seedlings.

Experiments with the moss Physcomitrella patens, however, have shown that choice of the gelling agent – agar or Gelrite – does influence phytohormone sensitivity of the plant cell culture.^[45]

Other uses

Agar is used:

As an impression material in dentistry.
As a medium to precisely orient the tissue specimen and secure it by agar pre-embedding (especially useful for small endoscopy biopsy specimens) for histopathology processing^[46]
To make salt bridges and gel plugs for use in electrochemistry.
In formicariums as a transparent substitute for sand and a source of nutrition.
As a natural ingredient in forming modeling clay for young children to play with.
As an allowed biofertilizer component in organic farming.^[47]
As a substrate for precipitin reactions in immunology.
At different times as a substitute for gelatin in photographic emulsions, arrowroot in preparing silver paper and as a substitute for fish glue in resist etching.^[48]
As an MRI elastic gel phantom to mimic tissue mechanical properties in Magnetic Resonance Elastography^[49]
In the Arts, for example in "microbial art" in which agar acts as canvas, and microbes as a form of paint

Gelidium agar is used primarily for bacteriological plates. Gracilaria agar is used mainly in food applications.

In 2016, AMAM, a Japanese company, developed a prototype for agar-based commercial packaging system called Agar Plasticity, intended as a replacement for oil-based plastic packaging.^[50]^[51]

References

↑ Shimamura, Natsu (August 4, 2010). "Agar". The Tokyo Foundation. Retrieved 19 December 2016.
↑ Oxford Dictionary of English (2nd ed.). 2005.
↑ Balfour, Edward Green (1871). "agar". Cyclopædia of India and of eastern and southern Asia, commercial, industrial and scientific: products of the mineral, vegetable and animal kingdoms, useful arts and manufactures. Scottish and Adelphi Presses. p. 50.
↑ ^4.0 ^4.1 Davidson, Alan (2006). The Oxford Companion to Food. Oxford University Press. ISBN 978-0-19-280681-9.
↑ Williams, Peter W.; Phillips, Glyn O. (2000). "2: Agar". Handbook of hydrocolloids. Cambridge, England: Woodhead. p. 91. ISBN 1-85573-501-6. Agar is made from seaweed and it is attracted to bacteria.
↑ "Showing Food Agar". The Metabolomics Innovation Centre (TMIC). Archived from the original on 2021-05-09.
↑ Balfour, Edward Green (1857). Cyclopaedia of India and of Eastern and Southern Asia, commercial, industrial and scientific... Scottish Press. p. 13.
↑ Chapman, V. J.; Chapman, D.J. (1980). Seaweeds and their Uses (third ed.). Dordrecht: Springer Netherlands. p. 148. ISBN 978-94-009-5808-1.
↑ Balfour, Edward (1885). The cyclopædia of India and of eastern and southern Asia: commercial, industrial and scientific, products of the mineral, vegetable, and animal kingdoms, useful arts and manufactures. B. Quaritch. p. 71.
↑ Wilkinson, Richard James (1932). "agar". A Malay-English dictionary (romanised). I. Mytilene, Greece: Salavopoulos & Kinderlis. p. 9 – via TROVE, National Library of Australia.
↑ Agar-Agar Archived 2011-09-03 at the Wayback Machine at Agar-Agar.org
↑ "Agar-Agar". Botanical.com. Retrieved 22 January 2017.
↑ Hopley, David (2010). Encyclopedia of Modern Coral Reefs: Structure, Form and Process. Springer Science & Business Media. p. 31. ISBN 978-90-481-2638-5.
↑ ^14.0 ^14.1 ^14.2 ^14.3 Zaneveld, Jacques S. (1959). "The Utilization of Marine Algae in Tropical South and East Asia". Economic Botany. 13 (2): 89–131. Bibcode:1959EcBot..13...89Z. doi:10.1007/BF02859244. JSTOR 4288011.
↑ Wells, Albert H. (1916). "Possibilities of Gulaman Dagat as a Substitute for Gelatin in Food". The Philippine Journal of Science. 11: 267–271.
↑ de Noceda, Juan; de Sanlucar, Pedro (1754). Vocabulario de la lengua Tagala. Imprenta de la compañia de Jesus. pp. 101, 215.
↑ de Mentrida, Alonso (1841). Diccionario De La Lengua Bisaya, Hiligueina Y Haraya de la isla de Panay. En La Imprenta De D. Manuel Y De D. Felis Dayot. p. 380.
↑ Johari, Khir (Oct–Dec 2021). "The Role of Foraging in Malay Cuisine". BiblioAsia. Vol. 17 no. 3. National Library Board, Singapore. pp. 20–23.
↑ Zimbro, Mary Jo; Power, David A.; Miller, Sharon M.; Wilson, George E.; Johnson, Julie A. (eds.). Difco & BBL Manual (PDF) (2nd ed.). Becton Dickinson and Company. p. 6. Archived from the original (PDF) on 2012-06-06. Retrieved 2013-07-17.
↑ "All About Agar". Science Buddies. Retrieved 8 July 2025.
↑ Payen, Anselme (1859) "Sur la gélose et le nids de salangane" (On agar and swiftlet nests), Comptes rendus ..., 49 : 521–530, appended remarks 530–532.
↑ Robert Koch (10 April 1882) "Die Aetiologie der Tuberculose" (The etiology of tuberculosis), Berliner Klinische Wochenschrift (Berlin Clinical Weekly), 19 : 221–230. From p. 225: "Die Tuberkelbacillen lassen sich auch noch auf anderen Nährsubstraten kultiviren, wenn letztere ähnliche Eigenschaften wie das erstarrte Blutserum besitzen. So wachsen sie beispielsweise auf einer mit Agar-Agar bereiteten, bei Blutwärme hart bleibenden Gallerte, welche einen Zusatz von Fleischinfus und Pepton erhalten hat." (The tubercule bacilli can also be cultivated on other media, if the latter have properties similar to those of congealed blood serum. Thus they grow, for example, on a gelatinous mass which was prepared with agar-agar, which remains solid at blood temperature, and which has received a supplement of meat broth and peptone.)
↑ Smith, A. (November 1, 2005). "History of the Agar Plate". Laboratory News. Archived from the original on October 14, 2012. Retrieved November 3, 2012.
↑ Hesse, W. (1992). Translated by Gröschel, D.H.M. "Walther and Angelina Hesse–Early Contributors to Bacteriology" (PDF). ASM News. 58 (8): 425–428. Archived from the original (PDF) on 30 June 2017. Retrieved 22 January 2017.
↑ ^25.0 ^25.1 ^25.2 ^25.3 Lobban, Christopher S.; Wynne, Michael James (1981). The Biology of Seaweeds. University of California Press. pp. 734–735. ISBN 978-0-520-04585-9.
↑ Callaway, Ewen (8 December 2015). "Lab staple agar hit by seaweed shortage". Nature. Nature News. 528 (7581): 171–172. Bibcode:2015Natur.528..171C. doi:10.1038/528171a. PMID 26659158.
↑ ^27.0 ^27.1 "III: Properties, Manufacture, and Application of Seaweed Polysaccharides – Agar, Carageenan, and Algin". Training manual on Gracilaria culture and seaweed processing in China. Food and Agriculture Organization, United Nations. August 1990. Retrieved 2011-04-27.
↑ ^28.0 ^28.1 Rafael Armisen; Fernando Galatas (1987). "Chapter 1 – Production, Properties and Uses of Agar". In McHugh DJ (ed.). Production and Utilization of Products from Commercial Seaweeds. Food and Agriculture Organization, United Nations. ISBN 92-5-102612-2.
↑ "Agar". London South Bank University. Archived from the original on 2022-09-26. Retrieved 2023-03-21.
↑ Liu, Shijun; Usinger, Laurie (2008). "Agar and Its Use in Chemistry and Science". Science Buddies. Archived from the original on 3 June 2011. Retrieved 21 March 2023.
↑ "Hispanagar | Hysteresis, what is this peculiar word?". www.hispanagar.com. Retrieved 2023-03-21.
↑ Das, N.; Tripathi, N.; Basu, S.; Bose, C.; Maitra, S.; Khurana, S. (2015-07-23). "Progress in the development of gelling agents for improved culturability of microorganisms". Frontiers in Microbiology. 6 (698): 698. doi:10.3389/fmicb.2015.00698. PMC 4511835. PMID 26257708.
↑ "Agar-Agar: Definition, Producing and Uses". microbiologie-clinique.com. Retrieved 2023-03-21.
↑ ^34.0 ^34.1 Wings of Success. The Advantages of Being a Vegetarian: Selected Tips. pp. 9–10.
↑ Livlaid, Nele (2018). Plant-Based Made Easy: The Complete Practical Guide to Transitioning to Healthy Whole Food Diet. Nutriplanet (Swing & Step OU). ISBN 978-9949-88-246-5.
↑ ^36.0 ^36.1 Stobart, Tom (2016). Cook's Encyclopaedia. Grub Street Publishing. ISBN 978-1-910690-83-3.
↑ Zhang, Louisa; Seng, Teo Kiok; Hixson, Sue; Kwone, Eileen (2022). Home Economics S2 Tb (nt). Singapore: Longman. p. 145. ISBN 978-981-4079-47-1.
↑ Ash, Michael (2007). Handbook fo Fillers, Extenders, and Diluents. Synapse Information Resources. p. 233. ISBN 978-1-890595-96-8.
↑ Marden, Orison Swett (1921). "Constipation is a Crime". The New Success: Marden's Magazine. Lowrey-Marden. 5: 113.
↑ Agar-agar Review Sheet Archived 2015-06-20 at the Wayback Machine, USDA Organic Materials Review, April 1995.
↑ Lua error in package.lua at line 80: module 'Module:Citation/CS1/Suggestions' not found.
↑ Clark, David P.; Pazdernik, Nanette J.; McGehee, Michelle R. (2019-01-01), Clark, David P.; Pazdernik, Nanette J.; McGehee, Michelle R. (eds.), "Chapter 7 – Cloning Genes for Synthetic Biology", Molecular Biology (Third Edition), Academic Cell, pp. 199–239, doi:10.1016/b978-0-12-813288-3.00007-0, ISBN 978-0-12-813288-3, S2CID 91889487, retrieved 2022-12-12
↑ "Why Differential & Selective Media Remain Invaluable Tools". American Society for Microbiology. September 25, 2020.
↑ Kim, Se-Kwon (2011). Handbook of marine macroalgae: biotechnology and applied phycology (1st imp. ed.). Hoboken, NJ: John Wiley & Sons Inc. ISBN 978-0-470-97918-1.
↑ Birgit Hadeler; Sirkka Scholz; Ralf Reski (1995). "Gelrite and agar differently influence cytokinin-sensitivity of a moss". Journal of Plant Physiology. 146 (3): 369–371. Bibcode:1995JPPhy.146..369H. doi:10.1016/s0176-1617(11)82071-7.
↑ Yadav, Lokenddra; Thomas, Sarega; Kini, Usha (February 2015). "Improvised double-embedding technique of minute biopsies: A mega boon to histopathology laboratory". Indian Journal of Pathology and Microbiology. 58 (1): 12–6. doi:10.4103/0377-4929.151156. PMID 25673584.
↑ Integrated Organic Farming Handbook, H. Panda, Asia Pacific Business Press Inc., Oct 4, 2013
↑ Walker, Ernie (June 1986). "Black-and-White Photographic Chemistry" (PDF). NASA Technical Reports Server. Archived (PDF) from the original on 2022-10-09.
↑ McIlvain, Grace; Ganji, Elahe; Cooper, Catherine; Killian, Megan L.; Ogunnaike, Babatunde A.; Johnson, Curtis L. (September 2019). "Reliable preparation of agarose phantoms for use in quantitative magnetic resonance elastography". Journal of the Mechanical Behavior of Biomedical Materials. 97: 65–73. doi:10.1016/j.jmbbm.2019.05.001. PMC 6699912. PMID 31100487.
↑ "New Seaweed-Based Material Could Replace Plastic Packaging". Good Magazine. 2016-03-09. Retrieved 2016-04-03.
↑ "Design Looks Ahead". Fast Company. 26 January 2016. Retrieved 2016-04-03.

External links

File:Wiktionary-logo-en-v2.svg The dictionary definition of agar at Wiktionary

Template:Vegetarianism

[1] Shimamura, Natsu (August 4, 2010). "Agar". The Tokyo Foundation. Retrieved 19 December 2016.

[2] Oxford Dictionary of English (2nd ed.). 2005.

[3] Balfour, Edward Green (1871). "agar". Cyclopædia of India and of eastern and southern Asia, commercial, industrial and scientific: products of the mineral, vegetable and animal kingdoms, useful arts and manufactures. Scottish and Adelphi Presses. p. 50.

[oxford-4] 4.0 ^4.1 Davidson, Alan (2006). The Oxford Companion to Food. Oxford University Press. ISBN 978-0-19-280681-9.

[Williams2000-5] Williams, Peter W.; Phillips, Glyn O. (2000). "2: Agar". Handbook of hydrocolloids. Cambridge, England: Woodhead. p. 91. ISBN 1-85573-501-6. Agar is made from seaweed and it is attracted to bacteria.

[6] "Showing Food Agar". The Metabolomics Innovation Centre (TMIC). Archived from the original on 2021-05-09.

[7] Balfour, Edward Green (1857). Cyclopaedia of India and of Eastern and Southern Asia, commercial, industrial and scientific... Scottish Press. p. 13.

[8] Chapman, V. J.; Chapman, D.J. (1980). Seaweeds and their Uses (third ed.). Dordrecht: Springer Netherlands. p. 148. ISBN 978-94-009-5808-1.

[9] Balfour, Edward (1885). The cyclopædia of India and of eastern and southern Asia: commercial, industrial and scientific, products of the mineral, vegetable, and animal kingdoms, useful arts and manufactures. B. Quaritch. p. 71.

[Wilkinson-10] Wilkinson, Richard James (1932). "agar". A Malay-English dictionary (romanised). I. Mytilene, Greece: Salavopoulos & Kinderlis. p. 9 – via TROVE, National Library of Australia.

[11] Agar-Agar Archived 2011-09-03 at the Wayback Machine at Agar-Agar.org

[12] "Agar-Agar". Botanical.com. Retrieved 22 January 2017.

[13] Hopley, David (2010). Encyclopedia of Modern Coral Reefs: Structure, Form and Process. Springer Science & Business Media. p. 31. ISBN 978-90-481-2638-5.

[Zaneveld-14] 14.0 ^14.1 ^14.2 ^14.3 Zaneveld, Jacques S. (1959). "The Utilization of Marine Algae in Tropical South and East Asia". Economic Botany. 13 (2): 89–131. Bibcode:1959EcBot..13...89Z. doi:10.1007/BF02859244. JSTOR 4288011.

[15] Wells, Albert H. (1916). "Possibilities of Gulaman Dagat as a Substitute for Gelatin in Food". The Philippine Journal of Science. 11: 267–271.

[16] Noceda, Juan; de Sanlucar, Pedro (1754). Vocabulario de la lengua Tagala. Imprenta de la compañia de Jesus. pp. 101, 215.

[17] Mentrida, Alonso (1841). Diccionario De La Lengua Bisaya, Hiligueina Y Haraya de la isla de Panay. En La Imprenta De D. Manuel Y De D. Felis Dayot. p. 380.

[18] Johari, Khir (Oct–Dec 2021). "The Role of Foraging in Malay Cuisine". BiblioAsia. Vol. 17 no. 3. National Library Board, Singapore. pp. 20–23.

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[22] Robert Koch (10 April 1882) "Die Aetiologie der Tuberculose" (The etiology of tuberculosis), Berliner Klinische Wochenschrift (Berlin Clinical Weekly), 19 : 221–230. From p. 225: "Die Tuberkelbacillen lassen sich auch noch auf anderen Nährsubstraten kultiviren, wenn letztere ähnliche Eigenschaften wie das erstarrte Blutserum besitzen. So wachsen sie beispielsweise auf einer mit Agar-Agar bereiteten, bei Blutwärme hart bleibenden Gallerte, welche einen Zusatz von Fleischinfus und Pepton erhalten hat." (The tubercule bacilli can also be cultivated on other media, if the latter have properties similar to those of congealed blood serum. Thus they grow, for example, on a gelatinous mass which was prepared with agar-agar, which remains solid at blood temperature, and which has received a supplement of meat broth and peptone.)

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[FAO3-27] 27.0 ^27.1 "III: Properties, Manufacture, and Application of Seaweed Polysaccharides – Agar, Carageenan, and Algin". Training manual on Gracilaria culture and seaweed processing in China. Food and Agriculture Organization, United Nations. August 1990. Retrieved 2011-04-27.

[FAO1-28] 28.0 ^28.1 Rafael Armisen; Fernando Galatas (1987). "Chapter 1 – Production, Properties and Uses of Agar". In McHugh DJ (ed.). Production and Utilization of Products from Commercial Seaweeds. Food and Agriculture Organization, United Nations. ISBN 92-5-102612-2.

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[33] "Agar-Agar: Definition, Producing and Uses". microbiologie-clinique.com. Retrieved 2023-03-21.

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@@ Line 4: / Line 4: @@
 [[File:Agarplate redbloodcells edit.jpg|thumb|A [[blood agar]] plate used to culture bacteria and diagnose infection]]
-'''Agar''' ({{IPAc-en|ˈ|eɪ|ɡ|ɑːr}} or {{IPAc-en|ˈ|ɑː|g|ər}}), or '''agar-agar''', is a [[Gelling agent|jelly-like substance]] consisting of  [[polysaccharides]] obtained from the [[cell wall]]s of some species of [[red algae]], primarily from the ''[[Gracilaria]]'' genus (Irish moss, ogonori) and the [[Gelidiaceae]] family (tengusa).<ref>{{cite web |last=Shimamura |first=Natsu |date=August 4, 2010 |title=Agar |website=The Tokyo Foundation |url=http://www.tokyofoundation.org/en/topics/japanese-traditional-foods/vol.-4-agar |access-date=19 December 2016}}</ref><ref>{{cite book |year=2005 |title=Oxford Dictionary of English |edition=2nd |title-link=Oxford Dictionary of English}}</ref> As found in nature, agar is a mixture of two components, the linear polysaccharide [[agarose]] and a heterogeneous mixture of smaller molecules called [[agaropectin]].<ref name=Williams2000>{{cite book |last1=Williams |first1=Peter W. |last2=Phillips |first2=Glyn O. |year=2000 |title=Handbook of hydrocolloids |chapter=2: Agar |chapter-url=https://books.google.com/books?id=dXS7qnh-ZOEC&pg=PA28 |publisher=Woodhead |location=Cambridge, England |isbn=1-85573-501-6 |page=91 |quote=Agar is made from seaweed and it is attracted to bacteria.}}</ref>  It forms the supporting structure in the cell walls of certain species of algae and is released on boiling. These algae are known as [[agarophyte]]s, belonging to the [[Rhodophyta]] (red algae) phylum.<ref>{{cite book |last=Balfour |first=Edward Green |author-link=Edward Balfour |year=1871 |title=Cyclopædia of India and of eastern and southern Asia, commercial, industrial and scientific: products of the mineral, vegetable and animal kingdoms, useful arts and manufactures |chapter=agar |chapter-url=https://archive.org/details/cyclopdiaindiaa00unkngoog/page/n63 | publisher=Scottish and Adelphi Presses |page=50}}</ref><ref name=oxford>{{cite book |last=Davidson |first=Alan |date=2006 |title=The Oxford Companion to Food |publisher=Oxford University Press |isbn=978-0-19-280681-9 |url=https://books.google.com/books?id=JTr-ouCbL2AC}}</ref>  The processing of food-grade agar removes the agaropectin, and the commercial product is essentially pure agarose.
+'''Agar''' ({{IPAc-en|ˈ|eɪ|ɡ|ɑːr}} or {{IPAc-en|ˈ|ɑː|g|ər}}), or '''agar-agar''', is a [[Gelling agent|jelly-like substance]] consisting of [[polysaccharides]] obtained from the [[cell wall]]s of some species of [[red algae]] (phylum [[Rhodophyta]]) primarily from the ''[[Gracilaria]]'' genus (Irish moss, ogonori) and the [[Gelidiaceae]] family (tengusa).<ref>{{cite web |last=Shimamura |first=Natsu |date=August 4, 2010 |title=Agar |website=The Tokyo Foundation |url=http://www.tokyofoundation.org/en/topics/japanese-traditional-foods/vol.-4-agar |access-date=19 December 2016}}</ref><ref>{{cite book |year=2005 |title=Oxford Dictionary of English |edition=2nd |title-link=Oxford Dictionary of English}}</ref> These algae are known as [[agarophyte]]s.<ref>{{cite book |last=Balfour |first=Edward Green |author-link=Edward Balfour |year=1871 |title=Cyclopædia of India and of eastern and southern Asia, commercial, industrial and scientific: products of the mineral, vegetable and animal kingdoms, useful arts and manufactures |chapter=agar |chapter-url=https://archive.org/details/cyclopdiaindiaa00unkngoog/page/n63 | publisher=Scottish and Adelphi Presses |page=50}}</ref><ref name="oxford">{{cite book |last=Davidson |first=Alan |date=2006 |title=The Oxford Companion to Food |publisher=Oxford University Press |isbn=978-0-19-280681-9 |url=https://books.google.com/books?id=JTr-ouCbL2AC}}</ref>
+As found in nature, agar is a mixture of two components, the linear polysaccharide [[agarose]] and a heterogeneous mixture of smaller molecules called [[agaropectin]].<ref name="Williams2000">{{cite book |last1=Williams |first1=Peter W. |last2=Phillips |first2=Glyn O. |year=2000 |title=Handbook of hydrocolloids |chapter=2: Agar |chapter-url=https://books.google.com/books?id=dXS7qnh-ZOEC&pg=PA28 |publisher=Woodhead |location=Cambridge, England |isbn=1-85573-501-6 |page=91 |quote=Agar is made from seaweed and it is attracted to bacteria.}}</ref> It forms the supporting structure in the cell walls of certain species of algae, and is released on boiling. The processing of food-grade agar removes the agaropectin, and the commercial product is essentially pure agarose.
 Agar has been used as an ingredient in [[dessert]]s throughout Asia and also as a solid [[Substrate (biology)|substrate]] to contain [[Growth medium|culture media]] for [[Microbiology|microbiological]] work. Agar can be used as a [[laxative]]; an [[appetite suppressant]]; a [[vegan]] substitute for [[gelatin]]; a thickener for [[soup]]s; in [[Fruit preserves#Jelly|fruit preserves]], ice cream, and other desserts; as a clarifying agent in [[brewing]]; and for [[sizing]] paper and fabrics.<ref>{{cite web |title=Showing Food Agar |website=The Metabolomics Innovation Centre (TMIC) |url=https://foodb.ca/foods/FOOD00284 |url-status=live |archive-url=https://web.archive.org/web/20210509052540/https://foodb.ca/foods/FOOD00284 |archive-date=2021-05-09}}</ref><ref>{{cite book |last=Balfour |first=Edward Green |year=1857 |title=Cyclopaedia of India and of Eastern and Southern Asia, commercial, industrial and scientific... |publisher=Scottish Press |page=13 |url=https://archive.org/details/b28708921_0002/page/13}}</ref>
 == Etymology ==
-The word ''agar'' comes from '''agar-agar''', the [[Malay language|Malay]] name for red algae (''[[Gigartina]]'', ''[[Eucheuma]]'',<ref>{{cite book |last1=Chapman |first1=V. J. |last2=Chapman |first2=D.J. |date=1980 |title=Seaweeds and their Uses |edition=third |publisher=Springer Netherlands |location=Dordrecht |isbn=978-94-009-5808-1 |page=148}}</ref> ''[[Gracilaria]]'') from which the jelly is produced.<ref>{{cite book |last=Balfour |first=Edward |year=1885 |title=The cyclopædia of India and of eastern and southern Asia: commercial, industrial and scientific, products of the mineral, vegetable, and animal kingdoms, useful arts and manufactures |publisher=B. Quaritch |page=71 |url=https://archive.org/details/in.ernet.dli.2015.283118/page/n76}}</ref><ref name=Wilkinson>{{cite encyclopedia |last=Wilkinson |first=Richard James |date=1932 |title=agar |dictionary=A Malay-English dictionary (romanised) |publisher=Salavopoulos & Kinderlis |location=Mytilene, Greece |volume=I |page=9 |via=[[Trove|TROVE]], [[National Library of Australia]] |url=https://nla.gov.au/nla.obj-60272771/view?partId=nla.obj-435838799#page/n18/}}</ref> It is also known as '''kanten''' ({{langx|ja|寒天}}) (from the phrase ''<nowiki />'''kan'''-zarashi [[Tokoroten|tokoro'''ten''']]'' ({{lang|ja|寒曬心太}}) or "cold-exposed agar"), '''Japanese isinglass''',  '''China grass''', '''Ceylon moss''', and '''Jaffna moss'''.<ref>[http://www.agar-agar.org/en/ Agar-Agar] {{Webarchive|url=https://web.archive.org/web/20110903170258/http://www.agar-agar.org/en/ |date=2011-09-03 }} at Agar-Agar.org</ref> ''[[Gracilaria edulis]]'' or its synonym ''G. lichenoides'' is specifically referred to as '''agal-agal''' or '''Ceylon agar'''.<ref>{{cite web |title=Agar-Agar |publisher=Botanical.com |url=http://www.botanical.com/botanical/mgmh/a/agara012.html |access-date=22 January 2017}}</ref>
+The word ''agar'' comes from '''agar-agar''', the [[Malay language|Malay]] name for red algae (''[[Gigartina]]'', ''[[Eucheuma]]'',<ref>{{cite book |last1=Chapman |first1=V. J. |last2=Chapman |first2=D.J. |date=1980 |title=Seaweeds and their Uses |edition=third |publisher=Springer Netherlands |location=Dordrecht |isbn=978-94-009-5808-1 |page=148}}</ref> ''[[Gracilaria]]'') from which the jelly is produced.<ref>{{cite book |last=Balfour |first=Edward |year=1885 |title=The cyclopædia of India and of eastern and southern Asia: commercial, industrial and scientific, products of the mineral, vegetable, and animal kingdoms, useful arts and manufactures |publisher=B. Quaritch |page=71 |url=https://archive.org/details/in.ernet.dli.2015.283118/page/n76}}</ref><ref name=Wilkinson>{{cite encyclopedia |last=Wilkinson |first=Richard James |date=1932 |title=agar |dictionary=A Malay-English dictionary (romanised) |publisher=Salavopoulos & Kinderlis |location=Mytilene, Greece |volume=I |page=9 |via=[[Trove|TROVE]], [[National Library of Australia]] |url=https://nla.gov.au/nla.obj-60272771/view?partId=nla.obj-435838799#page/n18/}}</ref> It is also known as '''kanten''' ({{langx|ja|寒天}}) (from the phrase '''''kan'''-zarashi [[Tokoroten|tokoro'''ten''']]'' ({{lang|ja|寒晒し心太}}) or "cold-exposed agar"), '''Japanese isinglass''', '''China grass''', '''Ceylon moss''', and '''Jaffna moss'''.<ref>[http://www.agar-agar.org/en/ Agar-Agar] {{Webarchive|url=https://web.archive.org/web/20110903170258/http://www.agar-agar.org/en/ |date=2011-09-03 }} at Agar-Agar.org</ref> ''[[Gracilaria edulis]]'' or its synonym ''G.&nbsp;lichenoides'' is specifically referred to as '''agal-agal''' or '''Ceylon agar'''.<ref>{{cite web |title=Agar-Agar |publisher=Botanical.com |url=http://www.botanical.com/botanical/mgmh/a/agara012.html |access-date=22 January 2017}}</ref>
 == History ==
 {{See also|Edible seaweed|Seaweed farming}}
 [[File:Ogo.jpg|thumb|upright|[[Ogonori]], the most common red algae used to make agar]]
-Macroalgae have been used widely as food by coastal cultures, especially in [[Southeast Asia]].<ref>{{cite book |last=Hopley |first=David |year=2010 |title=Encyclopedia of Modern Coral Reefs: Structure, Form and Process |publisher=Springer Science & Business Media |isbn=9789048126385 |page=31 |url=https://books.google.com/books?id=5umXDDmqxwIC&q=agar+gelling+southeast+asia+dessert&pg=PA31}}</ref><ref name="Zaneveld"/> In the [[Philippines]], ''[[Gracilaria]]'', known as ''[[gulaman]]'' (also ''guraman'', ''gar-garao'', or ''gulaman dagat'', among other names) in [[Tagalog language|Tagalog]], have been harvested and used as food for centuries, eaten both fresh or sun-dried and turned into jellies. The earliest historical attestation is from the ''[[Vocabulario de la lengua tagala]]'' (1754) by the [[Jesuit]] priests Juan de Noceda and Pedro de Sanlucar, where ''golaman'' or ''gulaman'' was defined as ''"una yerva, de que se haze conserva a modo de Halea, naze en la mar"'' ("a herb, from which a jam-like preserve is made, grows in the sea"), with an additional entry for ''guinolaman'' to refer to food made with the jelly.<ref>{{cite journal |last=Wells |first=Albert H. |date=1916 |title=Possibilities of Gulaman Dagat as a Substitute for Gelatin in Food |journal=The Philippine Journal of Science |volume=11 |pages=267–271}}</ref><ref>{{cite book |last1=de Noceda |first1=Juan |last2=de Sanlucar |first2=Pedro |date=1754 |title=Vocabulario de la lengua Tagala |publisher=Imprenta de la compañia de Jesus |pages=101,215}}</ref><ref name=Zaneveld/>
+Macroalgae have been used widely as food by coastal cultures, especially in [[Southeast Asia]].<ref>{{cite book |last=Hopley |first=David |year=2010 |title=Encyclopedia of Modern Coral Reefs: Structure, Form and Process |publisher=Springer Science & Business Media |isbn=978-90-481-2638-5 |page=31 |url=https://books.google.com/books?id=5umXDDmqxwIC&q=agar+gelling+southeast+asia+dessert&pg=PA31}}</ref><ref name="Zaneveld"/> In the [[Philippines]], ''[[Gracilaria]]'', known as ''[[gulaman]]'' (also ''guraman'', ''gar-garao'', or ''gulaman dagat'', among other names) in [[Tagalog language|Tagalog]], have been harvested and used as food for centuries, eaten both fresh or sun-dried and turned into jellies. The earliest historical attestation is from the ''[[Vocabulario de la lengua tagala]]'' (1754) by the [[Jesuit]] priests Juan de Noceda and Pedro de Sanlucar, where ''golaman'' or ''gulaman'' was defined as ''"una yerva, de que se haze conserva a modo de Halea, naze en la mar"'' ("a herb, from which a jam-like preserve is made, grows in the sea"), with an additional entry for ''guinolaman'' to refer to food made with the jelly.<ref>{{cite journal |last=Wells |first=Albert H. |date=1916 |title=Possibilities of Gulaman Dagat as a Substitute for Gelatin in Food |journal=The Philippine Journal of Science |volume=11 |pages=267–271}}</ref><ref>{{cite book |last1=de Noceda |first1=Juan |last2=de Sanlucar |first2=Pedro |date=1754 |title=Vocabulario de la lengua Tagala |publisher=Imprenta de la compañia de Jesus |pages=101, 215}}</ref><ref name=Zaneveld/>
-[[Carrageenan]], derived from gusô (''[[Eucheuma]]'' spp.), which also congeals into a gel-like texture is also used similarly among the [[Visayan peoples]] and have been recorded in the even earlier ''Diccionario De La Lengua Bisaya, Hiligueina y Haraia de la isla de Panay y Sugbu y para las demas islas'' (c.1637) of the [[Augustinians|Augustinian]] missionary [[:es:Alonso de Méntrida|Alonso de Méntrida]] {{In lang|es}}. In the book, Méntrida describes gusô as being cooked until it melts, and then allowed to congeal into a sour dish.<ref>{{cite book |last1=de Mentrida |first1=Alonso |date=1841 |title=Diccionario De La Lengua Bisaya, Hiligueina Y Haraya de la isla de Panay |publisher=En La Imprenta De D. Manuel Y De D. Felis Dayot |page=380}}</ref>
+[[Carrageenan]], derived from gusô (''[[Eucheuma]]'' spp.), which also congeals into a gel-like texture is also used similarly among the [[Visayan peoples]] and have been recorded in the even earlier ''Diccionario De La Lengua Bisaya, Hiligueina y Haraia de la isla de Panay y Sugbu y para las demas islas'' ({{Circa|1637}}) of the [[Augustinians|Augustinian]] missionary [[:es:Alonso de Méntrida|Alonso de Méntrida]] {{In lang|es}}. In the book, Méntrida describes gusô as being cooked until it melts, and then allowed to congeal into a sour dish.<ref>{{cite book |last1=de Mentrida |first1=Alonso |date=1841 |title=Diccionario De La Lengua Bisaya, Hiligueina Y Haraya de la isla de Panay |publisher=En La Imprenta De D. Manuel Y De D. Felis Dayot |page=380}}</ref>
-In [[Ambon Island]] in the [[Maluku Islands]] of [[Indonesia]], agar is extracted from ''Graciliaria'' and eaten as a type of pickle or a sauce.<ref name="Zaneveld"/> Jelly seaweeds were also favoured and foraged by [[Malays (ethnic group)|Malay]] communities living on the coasts of the [[Riau Archipelago]] and [[Singapore]] in Southeast Asia for centuries. 19th century records indicate that dried ''Graciliaria'' were one of the bulk exports of [[British Malaya]] to China. Poultices made from agar were also used for swollen knee joints and sores in [[Johore]] and Singapore.<ref name=Zaneveld>{{cite journal |last=Zaneveld |first=Jacques S. |date=1959 |title=The Utilization of Marine Algae in Tropical South and East Asia |journal=Economic Botany |doi=10.1007/BF02859244 |jstor=4288011 |bibcode=1959EcBot..13...89Z |volume=13 |issue=2 |pages=89–131 |url=https://www.jstor.org/stable/4288011|url-access=subscription }}</ref><ref>{{cite magazine |last=Johari |first=Khir |date=Oct–Dec 2021 |title=The Role of Foraging in Malay Cuisine |magazine=BiblioAsia |publisher=[[National Library Board]], Singapore |volume=17 |issue=3 |pages=20–23 |url=https://biblioasia.nlb.gov.sg/vol-17/issue-3/oct-dec-2021/}}</ref>
+In [[Ambon Island]] in the [[Maluku Islands]] of [[Indonesia]], agar is extracted from ''Graciliaria'' and eaten as a type of pickle or a sauce.<ref name="Zaneveld"/> Jelly seaweeds were also favoured and foraged by [[Malays (ethnic group)|Malay]] communities living on the coasts of the [[Riau Archipelago]] and [[Singapore]] in Southeast Asia for centuries. 19th century records indicate that dried ''Graciliaria'' were one of the bulk exports of [[British Malaya]] to China. Poultices made from agar were also used for swollen knee joints and sores in [[Johore]] and Singapore.<ref name=Zaneveld>{{cite journal |last=Zaneveld |first=Jacques S. |date=1959 |title=The Utilization of Marine Algae in Tropical South and East Asia |journal=Economic Botany |doi=10.1007/BF02859244 |jstor=4288011 |bibcode=1959EcBot..13...89Z |volume=13 |issue=2 |pages=89–131 }}</ref><ref>{{cite magazine |last=Johari |first=Khir |date=Oct–Dec 2021 |title=The Role of Foraging in Malay Cuisine |magazine=BiblioAsia |publisher=[[National Library Board]], Singapore |volume=17 |issue=3 |pages=20–23 |url=https://biblioasia.nlb.gov.sg/vol-17/issue-3/oct-dec-2021/}}</ref>
-The application of agar as a food additive in Japan is alleged to have been discovered in 1658 by Mino Tarōzaemon ({{lang|ja|{{linktext|美濃}} {{linktext|太郎}}{{linktext|左|衞|門}}}}), an innkeeper in current [[Fushimi-ku, Kyoto]] who, according to legend, was said to have discarded surplus seaweed soup ([[Tokoroten]]) and noticed that it gelled later after a winter night's freezing.<ref name=DifcoMan>{{cite book |editor1-last=Zimbro |editor1-first=Mary Jo |editor2-last=Power |editor2-first=David A. |editor3-last=Miller |editor3-first=Sharon M. |editor4-last=Wilson |editor4-first=George E. |editor5-last=Johnson |editor5-first=Julie A. |title=Difco & BBL Manual |edition=2nd |publisher=Becton Dickinson and Company |page=6 |url=http://www.bd.com/ds/technicalCenter/misc/difcobblmanual_2nded_lowres.pdf |access-date=2013-07-17 |url-status=dead |archive-url=https://web.archive.org/web/20120606174455/http://www.bd.com/ds/technicalCenter/misc/difcobblmanual_2nded_lowres.pdf |archive-date=2012-06-06}}</ref> It should be noted, however, that agar solidifies at room temperature and does not need to be frozen.<ref>{{cite web |title=All About Agar |url=https://www.sciencebuddies.org/science-fair-projects/references/grow-microbes-agar |website=Science Buddies |access-date=8 July 2025}}</ref>
+The application of agar as a food additive in Japan is alleged to have been discovered in 1658 by Mino Tarōzaemon ({{lang|ja|{{linktext|美濃}} {{linktext|太郎}}{{linktext|左|衞|門}}}}), an innkeeper in current [[Fushimi-ku, Kyoto]], who, according to legend, was said to have discarded surplus seaweed soup ([[Tokoroten]]) and noticed that it gelled later after a winter night's freezing.<ref name=DifcoMan>{{cite book |editor1-last=Zimbro |editor1-first=Mary Jo |editor2-last=Power |editor2-first=David A. |editor3-last=Miller |editor3-first=Sharon M. |editor4-last=Wilson |editor4-first=George E. |editor5-last=Johnson |editor5-first=Julie A. |title=Difco & BBL Manual |edition=2nd |publisher=Becton Dickinson and Company |page=6 |url=http://www.bd.com/ds/technicalCenter/misc/difcobblmanual_2nded_lowres.pdf |access-date=2013-07-17 |archive-url=https://web.archive.org/web/20120606174455/http://www.bd.com/ds/technicalCenter/misc/difcobblmanual_2nded_lowres.pdf |archive-date=2012-06-06}}</ref> Agar normally solidifies at room temperature without the need to freeze.<ref>{{cite web |title=All About Agar |url=https://www.sciencebuddies.org/science-fair-projects/references/grow-microbes-agar |website=Science Buddies |access-date=8 July 2025}}</ref>
 Agar was first subjected to chemical analysis in 1859 by the French chemist [[Anselme Payen]], who had obtained agar from the marine algae ''Gelidium corneum''.<ref>Payen, Anselme (1859) [http://gallica.bnf.fr/ark:/12148/bpt6k3006f/f523.image.langEN "Sur la gélose et le nids de salangane"] (On agar and swiftlet nests), ''Comptes rendus'' ..., '''49''' : 521–530, appended remarks 530–532.</ref>
-Beginning in the late 19th century, agar began to be used as a solid medium for growing various microbes. Agar was first described for use in microbiology in 1882 by the German microbiologist [[Walther Hesse]], an assistant working in [[Robert Koch|Robert Koch's]] laboratory, on the suggestion of his wife [[Fanny Hesse]].<ref>Robert Koch (10 April 1882) [http://babel.hathitrust.org/cgi/pt?id=mdp.39015020075001;view=1up;seq=235 "Die Aetiologie der Tuberculose"] (The etiology of tuberculosis), ''Berliner Klinische Wochenschrift'' (Berlin Clinical Weekly), '''19''' :  221–230.  From p. 225:  ''"Die Tuberkelbacillen lassen sich auch noch auf anderen Nährsubstraten kultiviren, wenn letztere ähnliche Eigenschaften wie das erstarrte Blutserum besitzen.  So wachsen sie beispielsweise auf einer mit Agar-Agar bereiteten, bei Blutwärme hart bleibenden Gallerte, welche einen Zusatz von Fleischinfus und Pepton erhalten hat."'' (The tubercule bacilli can also be cultivated on other media, if the latter have properties similar to those of congealed blood serum.  Thus they grow, for example, on a gelatinous mass which was prepared with agar-agar, which remains solid at blood temperature, and which has received a supplement of meat broth and peptone.)</ref><ref name=ln>{{cite magazine |last=Smith |first=A. |date=November 1, 2005 |title=History of the Agar Plate |magazine=Laboratory News |url=http://www.labnews.co.uk/features/history-of-the-agar-plate/ |access-date=November 3, 2012 |url-status=dead |archive-url=https://web.archive.org/web/20121014060019/http://www.labnews.co.uk/features/history-of-the-agar-plate/ |archive-date=October 14, 2012}}</ref> Agar quickly supplanted gelatin as the base of microbiological media, due to its higher melting temperature, allowing microbes to be grown at higher temperatures without the media liquefying.<ref name=hesse>{{cite journal |last=Hesse |first=W. |translator=Gröschel, D.H.M. |year=1992 |title=Walther and Angelina Hesse–Early Contributors to Bacteriology |journal=ASM News |volume=58 |issue=8 |pages=425–428 |url=http://www.asm.org/ccLibraryFiles/FILENAME/0000000227/580892p425.pdf |access-date=22 January 2017 |url-status=dead |archive-url=https://web.archive.org/web/20170630173511/https://www.asm.org/ccLibraryFiles/FILENAME/0000000227/580892p425.pdf |archive-date=30 June 2017}}</ref>
+Beginning in the late 19th century, agar began to be used as a solid medium for growing various microbes. Agar was first described for use in microbiology in 1882 by the German microbiologist [[Walther Hesse]], an assistant working in [[Robert Koch|Robert Koch's]] laboratory, on the suggestion of his wife [[Fanny Hesse]].<ref>Robert Koch (10 April 1882) [http://babel.hathitrust.org/cgi/pt?id=mdp.39015020075001;view=1up;seq=235 "Die Aetiologie der Tuberculose"] (The etiology of tuberculosis), ''Berliner Klinische Wochenschrift'' (Berlin Clinical Weekly), '''19''' :  221–230.  From p. 225:  ''"Die Tuberkelbacillen lassen sich auch noch auf anderen Nährsubstraten kultiviren, wenn letztere ähnliche Eigenschaften wie das erstarrte Blutserum besitzen.  So wachsen sie beispielsweise auf einer mit Agar-Agar bereiteten, bei Blutwärme hart bleibenden Gallerte, welche einen Zusatz von Fleischinfus und Pepton erhalten hat."'' (The tubercule bacilli can also be cultivated on other media, if the latter have properties similar to those of congealed blood serum.  Thus they grow, for example, on a gelatinous mass which was prepared with agar-agar, which remains solid at blood temperature, and which has received a supplement of meat broth and peptone.)</ref><ref name=ln>{{cite magazine |last=Smith |first=A. |date=November 1, 2005 |title=History of the Agar Plate |magazine=Laboratory News |url=http://www.labnews.co.uk/features/history-of-the-agar-plate/ |access-date=November 3, 2012 |archive-url=https://web.archive.org/web/20121014060019/http://www.labnews.co.uk/features/history-of-the-agar-plate/ |archive-date=October 14, 2012}}</ref> Agar quickly supplanted gelatin as the base of microbiological media, due to its higher melting temperature, allowing microbes to be grown at higher temperatures without the media liquefying.<ref name=hesse>{{cite journal |last=Hesse |first=W. |translator=Gröschel, D.H.M. |year=1992 |title=Walther and Angelina Hesse–Early Contributors to Bacteriology |journal=ASM News |volume=58 |issue=8 |pages=425–428 |url=http://www.asm.org/ccLibraryFiles/FILENAME/0000000227/580892p425.pdf |access-date=22 January 2017 |archive-url=https://web.archive.org/web/20170630173511/https://www.asm.org/ccLibraryFiles/FILENAME/0000000227/580892p425.pdf |archive-date=30 June 2017}}</ref>
-With its newfound use in microbiology, agar production quickly increased. This production centered on Japan, which produced most of the world's agar until World War II.<ref name=Loban>{{cite book |last1=Lobban |first1=Christopher S. |last2=Wynne |first2=Michael James |year=1981 |title=The Biology of Seaweeds |publisher=University of California Press |isbn=9780520045859 |url=https://books.google.com/books?id=QG4tqjFPWJ0C&q=agar+gelling+malay+japan&pg=PA734 |pages=734–735}}</ref> However, with the outbreak of World War II, many nations were forced to establish domestic agar industries in order to continue microbiological research.<ref name=Loban/> Around the time of World War II, approximately 2,500 tons of agar were produced annually.<ref name=Loban/> By the mid-1970s, production worldwide had increased dramatically to approximately 10,000 tons each year.<ref name=Loban/> Since then, production of agar has fluctuated due to unstable and sometimes over-utilized seaweed populations.<ref>{{cite journal |last=Callaway |first=Ewen |date=8 December 2015 |title=Lab staple agar hit by seaweed shortage |journal=Nature |publisher=Nature News |doi=10.1038/528171a |doi-access=free |pmid=26659158 |bibcode=2015Natur.528..171C |volume=528 |issue=7581 |pages=171–172}}</ref>
+With its newfound use in microbiology, agar production quickly increased. This production centered on Japan, which produced most of the world's agar until World War II.<ref name=Loban>{{cite book |last1=Lobban |first1=Christopher S. |last2=Wynne |first2=Michael James |year=1981 |title=The Biology of Seaweeds |publisher=University of California Press |isbn=978-0-520-04585-9 |url=https://books.google.com/books?id=QG4tqjFPWJ0C&q=agar+gelling+malay+japan&pg=PA734 |pages=734–735}}</ref> However, with the outbreak of World War II, many nations were forced to establish domestic agar industries in order to continue microbiological research.<ref name=Loban/> Around the time of World War II, approximately 2,500 tons of agar were produced annually.<ref name=Loban/> By the mid-1970s, production worldwide had increased dramatically to approximately 10,000 tons each year.<ref name=Loban/> Since then, production of agar has fluctuated due to unstable and sometimes over-utilized seaweed populations.<ref>{{cite journal |last=Callaway |first=Ewen |date=8 December 2015 |title=Lab staple agar hit by seaweed shortage |journal=Nature |publisher=Nature News |doi=10.1038/528171a |doi-access=free |pmid=26659158 |bibcode=2015Natur.528..171C |volume=528 |issue=7581 |pages=171–172}}</ref>
 == Chemical composition ==
 [[File:Agarose polymere.svg|right|thumb|The structure of an [[agarose]] polymer]]
-Agar consists of a mixture of two [[polysaccharide]]s: agarose and agaropectin, with agarose making up about 70% of the mixture, while agaropectin makes about 30% of it.<ref name=FAO3/> Agarose is a linear polymer, made up of repeating units of [[Agarose#Structure|agarobiose]], a disaccharide made up of [[D-galactose]] and 3,6-anhydro-L-galactopyranose.<ref name=FAO1/> Agaropectin is a heterogeneous mixture of smaller molecules that occur in lesser amounts, and is made up of alternating units of D-galactose and L-galactose heavily modified with acidic side-groups, such as [[sulfate]], [[glucuronate]], and [[pyruvate]].<ref>{{cite web |access-date=2023-03-21 |url=https://water.lsbu.ac.uk/water/agar.html |title=Agar |archive-url=https://web.archive.org/web/20220926200632/https://water.lsbu.ac.uk/water/agar.html |archive-date=2022-09-26 |website=London South Bank University}}</ref><ref name=FAO3>{{cite book|chapter-url=http://www.fao.org/docrep/field/003/AB730E/AB730E03.htm |title=Training manual on Gracilaria culture and seaweed processing in China |chapter=III: Properties, Manufacture, and Application of Seaweed Polysaccharides – Agar, Carageenan, and Algin |publisher=Food and Agriculture Organization, United Nations|date=August 1990 |access-date=2011-04-27}}</ref><ref name=FAO1>{{cite book|chapter-url=http://www.fao.org/docrep/x5822e/x5822e03.htm |title=Production and Utilization of Products from Commercial Seaweeds|chapter=Chapter 1 – Production, Properties and Uses of Agar |author1=Rafael Armisen |author2=Fernando Galatas |publisher=Food and Agriculture Organization, United Nations |date=1987 |editor=McHugh DJ |isbn=92-5-102612-2}}</ref>
+Agar consists of a mixture of two [[polysaccharide]]s: agarose and agaropectin. Agarose constitutes about 70% of the mixture, while agaropectin constitutes about 30% of it.<ref name=FAO3/> Agarose is a linear polymer made up of repeating units of [[Agarose#Structure|agarobiose]], a disaccharide made up of [[D-galactose]] and 3,6-anhydro-L-galactopyranose.<ref name=FAO1/> Agaropectin is a heterogeneous mixture of smaller molecules that occur in lesser amounts, and is made up of alternating units of D-galactose and L-galactose heavily modified with acidic side-groups, such as [[sulfate]], [[glucuronate]], and [[pyruvate]].<ref>{{cite web |access-date=2023-03-21 |url=https://water.lsbu.ac.uk/water/agar.html |title=Agar |archive-url=https://web.archive.org/web/20220926200632/https://water.lsbu.ac.uk/water/agar.html |archive-date=2022-09-26 |website=London South Bank University}}</ref><ref name=FAO3>{{cite book|chapter-url=http://www.fao.org/docrep/field/003/AB730E/AB730E03.htm |title=Training manual on Gracilaria culture and seaweed processing in China |chapter=III: Properties, Manufacture, and Application of Seaweed Polysaccharides – Agar, Carageenan, and Algin |publisher=Food and Agriculture Organization, United Nations|date=August 1990 |access-date=2011-04-27}}</ref><ref name=FAO1>{{cite book|chapter-url=http://www.fao.org/docrep/x5822e/x5822e03.htm |title=Production and Utilization of Products from Commercial Seaweeds|chapter=Chapter 1 – Production, Properties and Uses of Agar |author1=Rafael Armisen |author2=Fernando Galatas |publisher=Food and Agriculture Organization, United Nations |date=1987 |editor=McHugh DJ |isbn=92-5-102612-2}}</ref>
 == Physical properties ==
-Agar exhibits a phenomenon known as [[hysteresis#Liquid–solid-phase transitions|hysteresis]] whereby, when mixed with water, it solidifies and forms a [[gel]] below about {{convert|32–42|C|K F}}, which is called the [[gel point]], and melts above {{convert|85|C|K F}}, which is the [[melting point]].<ref>{{cite web|url=https://www.sciencebuddies.org/science-fair-projects/references/grow-microbes-agar |title=Agar and Its Use in Chemistry and Science |last1=Liu |first1=Shijun |last2=Usinger |first2=Laurie |date=2008<!-- latest source access date --> |website=Science Buddies |access-date=21 March 2023 |archive-url= https://web.archive.org/web/20110603081846/http://www.sciencebuddies.org/science-fair-projects/project_ideas/MicroBio_Agar.shtml| archive-date= 3 June 2011 | url-status= live}}</ref> [[Hysteresis]] is the property of having a difference between the gel point and melting point temperatures.<ref>{{Cite web |title=Hispanagar {{!}} Hysteresis, what is this peculiar word? |url=https://www.hispanagar.com/en/hysteresis-what-peculiar-word#:~:text=Hysteresis%20is,before. |access-date=2023-03-21 |website=www.hispanagar.com}}</ref> This property lends a suitable balance between easy melting and good gel stability at relatively high temperatures.<ref>{{Cite journal |last1=Das |first1=N. |last2=Tripathi |first2=N. |last3=Basu |first3=S. |last4=Bose |first4=C. |last5=Maitra |first5=S. |last6=Khurana |first6=S. |date=2015-07-23 |title=Progress in the development of gelling agents for improved culturability of microorganisms |journal=[[Frontiers in Microbiology]] |volume=6 |issue=698 |page=698 |doi=10.3389/fmicb.2015.00698 |pmid=26257708 |pmc=4511835 |doi-access=free }}</ref> Since many scientific applications require incubation at temperatures close to human body temperature (37&nbsp;°C), agar is more appropriate than other solidifying agents that melt at this temperature, such as gelatin.<ref>{{Cite web |title=Agar-Agar : Definition, Producing and Uses |url=https://microbiologie-clinique.com/laboratory-agar.html#:~:text=Agar-Agar%20quickly%20supplanted,liquefied. |access-date=2023-03-21 |website=microbiologie-clinique.com}}</ref>
+Agar exhibits a phenomenon known as [[hysteresis#Liquid–solid-phase transitions|hysteresis]] whereby, when mixed with water, it solidifies and forms a [[gel]] below about {{convert|32–42|C|K F}}, which is called the [[gel point]], and melts above {{convert|85|C|K F}}, which is the [[melting point]].<ref>{{cite web|url=https://www.sciencebuddies.org/science-fair-projects/references/grow-microbes-agar |title=Agar and Its Use in Chemistry and Science |last1=Liu |first1=Shijun |last2=Usinger |first2=Laurie |date=2008<!-- latest source access date --> |website=Science Buddies |access-date=21 March 2023 |archive-url= https://web.archive.org/web/20110603081846/http://www.sciencebuddies.org/science-fair-projects/project_ideas/MicroBio_Agar.shtml| archive-date= 3 June 2011 | url-status= live}}</ref> [[Hysteresis]] is the property of having a difference between the gel point and melting point temperatures.<ref>{{Cite web |title=Hispanagar {{!}} Hysteresis, what is this peculiar word? |url=https://www.hispanagar.com/en/hysteresis-what-peculiar-word#:~:text=Hysteresis%20is,before. |access-date=2023-03-21 |website=www.hispanagar.com}}</ref> This property lends a suitable balance between easy melting and good gel stability at relatively high temperatures.<ref>{{Cite journal |last1=Das |first1=N. |last2=Tripathi |first2=N. |last3=Basu |first3=S. |last4=Bose |first4=C. |last5=Maitra |first5=S. |last6=Khurana |first6=S. |date=2015-07-23 |title=Progress in the development of gelling agents for improved culturability of microorganisms |journal=[[Frontiers in Microbiology]] |volume=6 |issue=698 |page=698 |doi=10.3389/fmicb.2015.00698 |pmid=26257708 |pmc=4511835 |doi-access=free }}</ref> Since many scientific applications require incubation at temperatures close to human body temperature (37&nbsp;°C), agar is more appropriate than other solidifying agents that melt at this temperature, such as gelatin.<ref>{{Cite web |title=Agar-Agar: Definition, Producing and Uses |url=https://microbiologie-clinique.com/laboratory-agar.html#:~:text=Agar-Agar%20quickly%20supplanted,liquefied. |access-date=2023-03-21 |website=microbiologie-clinique.com}}</ref>
 ==Uses==
@@ Line 39: / Line 41: @@
 === Culinary ===
 [[File:Sago Gulaman.jpg|thumb|''[[Sago]] at [[gulaman]]'' in [[Filipino cuisine]] is made from agar (''[[gulaman]]''), pearl [[sago]], and sugar syrup flavored with [[Pandanus amaryllifolius|pandan]].|210x210px]]
-Agar-agar is a natural vegetable [[gelatin]] counterpart.<ref name=":0">{{Cite book |last=Wings of Success |title=The Advantages of Being a Vegetarian: Selected Tips |pages=9–10}}</ref><ref>{{Cite book |last=Livlaid |first=Nele |title=Plant-Based Made Easy: The Complete Practical Guide to Transitioning to Healthy Whole Food Diet |publisher=Nutriplanet (Swing & Step OU) |year=2018 |isbn=9789949882465}}</ref> It is white and semi-[[translucent]] when sold in packages as washed and dried strips or in powdered form.<ref name=":0" /><ref name=":1">{{Cite book |last=Stobart |first=Tom |title=Cook's Encyclopaedia |publisher=Grub Street Publishing |year=2016 |isbn=9781910690833}}</ref> It can be used to make jellies,<ref>{{Cite book |last1=Zhang |first1=Louisa |title=Home Economics S2 Tb (nt) |last2=Seng |first2=Teo Kiok |last3=Hixson |first3=Sue |last4=Kwone |first4=Eileen |publisher=Longman |year=2022 |isbn=9789814079471 |location=Singapore |pages=145}}</ref> [[puddings]], and [[custard]]s.<ref>{{Cite book |last=Ash |first=Michael |title=Handbook fo Fillers, Extenders, and Diluents |publisher=Synapse Information Resources |year=2007 |isbn=9781890595968 |pages=233}}</ref> When making jelly, it is boiled in water until the solids dissolve. Sweetener, flavoring, coloring, fruits and or vegetables are then added, and the liquid is poured into [[molding (process)|molds]] to be served as desserts and vegetable [[aspic]]s or incorporated with other desserts such as a layer of jelly in a [[cake]].<ref name=":1" />
+Agar-agar is a natural vegetable [[gelatin]] counterpart.<ref name=":0">{{Cite book |last=Wings of Success |title=The Advantages of Being a Vegetarian: Selected Tips |pages=9–10}}</ref><ref>{{Cite book |last=Livlaid |first=Nele |title=Plant-Based Made Easy: The Complete Practical Guide to Transitioning to Healthy Whole Food Diet |publisher=Nutriplanet (Swing & Step OU) |year=2018 |isbn=978-9949-88-246-5}}</ref> It is white and semi-[[translucent]] when sold in packages as washed and dried strips or in powdered form.<ref name=":0" /><ref name=":1">{{Cite book |last=Stobart |first=Tom |title=Cook's Encyclopaedia |publisher=Grub Street Publishing |year=2016 |isbn=978-1-910690-83-3}}</ref> It can be used to make jellies,<ref>{{Cite book |last1=Zhang |first1=Louisa |title=Home Economics S2 Tb (nt) |last2=Seng |first2=Teo Kiok |last3=Hixson |first3=Sue |last4=Kwone |first4=Eileen |publisher=Longman |year=2022 |isbn=978-981-4079-47-1 |location=Singapore |pages=145}}</ref> [[puddings]], and [[custard]]s.<ref>{{Cite book |last=Ash |first=Michael |title=Handbook fo Fillers, Extenders, and Diluents |publisher=Synapse Information Resources |year=2007 |isbn=978-1-890595-96-8 |pages=233}}</ref> When making jelly, it is boiled in water until the solids dissolve. Sweetener, flavoring, coloring, fruits and or vegetables are then added, and the liquid is poured into [[molding (process)|molds]] to be served as desserts and vegetable [[aspic]]s or incorporated with other desserts such as a layer of jelly in a [[cake]].<ref name=":1" />
-Agar-agar is approximately 80% [[dietary fiber]], so it can serve as an intestinal regulator.<ref>{{Cite journal |last=Marden |first=Orison Swett |date=1921 |title=Constipation is a Crime |journal=The New Success: Marden's Magazine |publisher=Lowrey-Marden |volume=5 |pages=113}}</ref> Its bulking quality has been behind [[fad diet]]s in Asia, for example the ''kanten'' (the Japanese word for agar-agar<ref name="oxford" />) diet. Once ingested, ''kanten'' triples in size and absorbs water. This results in the consumers feeling fuller.
+Agar-agar is approximately 80% [[dietary fiber]], so it can serve as an intestinal regulator.<ref>{{Cite journal |last=Marden |first=Orison Swett |date=1921 |title=Constipation is a Crime |journal=The New Success: Marden's Magazine |publisher=Lowrey-Marden |volume=5 |page=113}}</ref> Its bulking quality has been behind [[fad diet]]s in Asia, for example the ''kanten'' (the Japanese word for agar-agar<ref name="oxford" />) diet. Once ingested, ''kanten'' triples in size and absorbs water. This results in the consumers feeling fuller.
 ==== Asian culinary ====
-One use of agar in [[Japanese cuisine]] is in ''[[anmitsu]]'', a dessert made of small cubes of agar jelly and served in a bowl with various fruits or other ingredients.{{citation needed|date=April 2024}} It is also the main ingredient in ''mizu yōkan'', another popular Japanese food.{{citation needed|date=April 2024}} In [[Philippine cuisine]], it is used to make the jelly bars in the various [[gulaman]] refreshments like ''[[sago't gulaman]]'', ''[[samalamig]]'', or desserts such as ''[[buko pandan]]'', ''agar flan'', ''[[halo-halo]]'', ''fruit cocktail jelly'', and the black and red ''gulaman'' used in various fruit salads.{{citation needed|date=April 2024}} In [[Vietnamese cuisine]], jellies made of flavored layers of agar-agar, called ''thạch'', are a popular dessert, and are often made in ornate molds for special occasions.{{citation needed|date=April 2024}} In [[Indian cuisine]], agar is used for making desserts.{{citation needed|date=April 2024}} In [[Burmese cuisine]], a sweet jelly known as ''kyauk kyaw'' is made from agar.{{citation needed|date=April 2024}} Agar jelly is widely used in Taiwanese [[bubble tea]].{{citation needed|date=April 2024}}
+One use of agar in [[Japanese cuisine]] is in ''[[anmitsu]]'', a dessert made of small cubes of agar jelly and served in a bowl with various fruits or other ingredients.{{citation needed|date=April 2024}} It is also the main ingredient in {{Lang|ja-Latn|mizu yōkan}}, another popular Japanese food.{{citation needed|date=April 2024}} In [[Philippine cuisine]], it is used to make the jelly bars in the various [[gulaman]] refreshments like ''[[sago't gulaman]]'', ''[[samalamig]]'', or desserts such as ''[[buko pandan]]'', ''agar flan'', ''[[halo-halo]]'', ''fruit cocktail jelly'', and the black and red ''gulaman'' used in various fruit salads.{{citation needed|date=April 2024}} In [[Vietnamese cuisine]], jellies made of flavored layers of agar-agar, called ''thạch'', are a popular dessert, and are often made in ornate molds for special occasions.{{citation needed|date=April 2024}} In [[Indian cuisine]], agar is used for making desserts.{{citation needed|date=April 2024}} In [[Burmese cuisine]], a sweet jelly known as ''kyauk kyaw'' is made from agar.{{citation needed|date=April 2024}} Agar jelly is widely used in Taiwanese [[bubble tea]].{{citation needed|date=April 2024}}
 ==== Other culinary ====
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 Different algae produce various types of agar. Each agar has unique properties that suit different purposes. Because of the agarose component, the agar solidifies. When heated, agarose has the potential to melt and then solidify. Because of this property, they are referred to as "physical gels". In contrast, [[polyacrylamide]] polymerization is an irreversible process, and the resulting products are known as chemical gels.
-There are a variety of different types of agar that support the growth of different microorganisms. A nutrient agar may be permissive, allowing for the cultivation of any non-fastidious microorganisms; a commonly used nutrient agar for bacteria is the Luria Bertani (LB) agar which contains [[lysogeny broth]], a nutrient-rich medium used for bacterial growth.<ref>{{Cite journal |date=2009-03-01 |title=LB agar |url=http://cshprotocols.cshlp.org/content/2009/3/pdb.rec11683 |journal=Cold Spring Harbor Protocols |language=en |volume=2009 |issue=3 |pages=pdb.rec11683 |doi=10.1101/pdb.rec11683 |issn=1940-3402|url-access=subscription }}</ref> Additionally, 2216 Marine Broth (MB) agar, with high salt content, is optimized for growing heterotrophic marine bacteria like those of the Vibrio genus, while Terrific Broth (TB) agar is used to non-selectively culture high yields of the bacterium ''E. coli''. More generally, enriched media is an agar variety that is infused with the necessary nutrients required by fastidious organisms to grow. Despite the large diversity of agar mediums, yeast extract is a common ingredient across all varieties as it is a macronutrient that provides a nitrogen source for all bacterial cell types.
+There are a variety of different types of agar that support the growth of different microorganisms. A nutrient agar may be permissive, allowing for the cultivation of any non-fastidious microorganisms; a commonly used nutrient agar for bacteria is the Luria Bertani (LB) agar which contains [[lysogeny broth]], a nutrient-rich medium used for bacterial growth.<ref>{{Cite journal |date=2009-03-01 |title=LB agar |url=http://cshprotocols.cshlp.org/content/2009/3/pdb.rec11683 |journal=Cold Spring Harbor Protocols |language=en |volume=2009 |issue=3 |article-number=pdb.rec11683 |doi=10.1101/pdb.rec11683 |issn=1940-3402|url-access=subscription }}</ref> Additionally, 2216 Marine Broth (MB) agar, with high salt content, is optimized for growing heterotrophic marine bacteria like those of the ''Vibrio'' genus, while Terrific Broth (TB) agar is used to non-selectively culture high yields of the bacterium ''E.&nbsp;coli''. More generally, enriched media is an agar variety that is infused with the necessary nutrients required by fastidious organisms to grow. Despite the large diversity of agar mediums, yeast extract is a common ingredient across all varieties as it is a macronutrient that provides a nitrogen source for all bacterial cell types.
 [[File:Lactose fementing (LF), and non-lactose fermenting (NLF) colonies on MacConkey agar.jpg|thumb]]
 Other fastidious organisms may require the addition of different biological fluids such as horse or sheep blood, serum, egg yolk, and so on.<ref>{{Citation |last1=Clark |first1=David P. |title=Chapter 7 – Cloning Genes for Synthetic Biology |date=2019-01-01 |url=https://www.sciencedirect.com/science/article/pii/B9780128132883000070 |work=Molecular Biology (Third Edition) |pages=199–239 |editor-last=Clark |editor-first=David P. |publisher=Academic Cell |language=en |doi=10.1016/b978-0-12-813288-3.00007-0 |isbn=978-0-12-813288-3 |access-date=2022-12-12 |last2=Pazdernik |first2=Nanette J. |last3=McGehee |first3=Michelle R. |s2cid=91889487 |editor2-last=Pazdernik |editor2-first=Nanette J. |editor3-last=McGehee |editor3-first=Michelle R.|url-access=subscription }}</ref> Agar plates can also be selective, and can be used to promote the growth of bacteria of interest while inhibiting others. A variety of chemicals may be added to create an environment favourable for specific types of bacteria or bacteria with certain properties, but not conducive for growth of others. For example, antibiotics may be added in cloning experiments whereby bacteria with antibiotic-resistant plasmid are selected.<ref>{{cite web |url=https://asm.org/Articles/2020/September/Why-Differential-Selective-Media-Are-Invaluable-To  |title=Why Differential & Selective Media Remain Invaluable Tools|date=September 25, 2020 |work=American Society for Microbiology}}</ref> In addition to antibiotic treated agar, other selective and indicator agar plates include TCBS agar and MacConkey agar. Thiosulfate citrate bile salts sucrose (TCBS) agar is used to differentiate Vibrio species based on their sucrose metabolism, since only some will metabolize the sucrose in the plate and change its pH. Indicator dyes included in the gel will display a visual change of the pH by changing the gel color from green to yellow. MacConkey agar contains bile salts and crystal violet to selectively grow gram-negative bacteria and differentiate between species using pH-indicator dyes that demonstrate lactose metabolism properties.
@@ Line 76: / Line 78: @@
 === Plant biology ===
-[[Image:Physcomitrella growing on agar plates.jpg|thumb|''[[Physcomitrella patens]]'' plants growing [[axenic]]ally [[in vitro]] on [[agar plate]]s. [[Petri dish]] has {{cvt|9|cm|adj=on}} diameter.]]
+[[Image:Physcomitrella growing on agar plates.jpg|thumb|''[[Physcomitrella patens]]'' plants growing [[axenic]]ally [[in vitro]] on [[agar plate]]s. [[Petri dish]] is {{cvt|9|cm|adj=on}} in diameter.]]
-Research grade agar is used extensively in [[plant]] biology as it is optionally supplemented with a nutrient and/or vitamin mixture that allows for seedling germination in Petri dishes under sterile conditions (given that the seeds are sterilized as well). Nutrient and/or vitamin supplementation for ''[[Arabidopsis thaliana]]'' is standard across most experimental conditions. [[Murashige and Skoog medium|Murashige & Skoog]] (MS) nutrient mix and [[Oluf L. Gamborg|Gamborg]]'s B5 vitamin mix in general are used. A 1.0% agar/0.44% MS+vitamin dH<sub>2</sub>O solution is suitable for growth media between normal growth temps.
+Research grade agar is used extensively in [[plant]] biology as it is optionally supplemented with a nutrient and/or vitamin mixture that allows for seedling germination in Petri dishes under sterile conditions (given that the seeds are sterilized as well). Nutrient and/or vitamin supplementation for ''[[Arabidopsis thaliana]]'' is standard across most experimental conditions. [[Murashige and Skoog medium|Murashige & Skoog]] (MS) nutrient mix and [[Oluf L. Gamborg|Gamborg]]'s B<sub>5</sub> vitamin mix in general are used. A 1.0% agar/0.44% MS+vitamin dH<sub>2</sub>O solution is suitable for growth media between normal growth temps.
-When using agar, within any growth medium, it is important to know that the solidification of the agar is pH-dependent. The optimal range for solidification is between 5.4 and 5.7.<ref>{{cite book|last1=Kim|first1=Se-Kwon|title=Handbook of marine macroalgae : biotechnology and applied phycology|date=2011|publisher=John Wiley & Sons Inc.|location=Hoboken, NJ|isbn=9780470979181|edition=1st imp.}}</ref> Usually, the application of potassium hydroxide is needed to increase the pH to this range. A general guideline is about 600 μl 0.1M KOH per 250 ml GM. This entire mixture can be sterilized using the liquid cycle of an [[autoclave]].
+When using agar, within any growth medium, it is important to know that the solidification of the agar is pH-dependent. The optimal range for solidification is between 5.4 and 5.7.<ref>{{cite book|last1=Kim|first1=Se-Kwon|title=Handbook of marine macroalgae: biotechnology and applied phycology|date=2011|publisher=John Wiley & Sons Inc.|location=Hoboken, NJ|isbn=978-0-470-97918-1|edition=1st imp.}}</ref> Usually, the application of potassium hydroxide is needed to increase the pH to this range. A general guideline is about 600 μl 0.1M KOH per 250 ml GM. This entire mixture can be sterilized using the liquid cycle of an [[autoclave]].
 This medium nicely lends itself to the application of specific concentrations of phytohormones etc. to induce specific growth patterns in that one can easily prepare a solution containing the desired amount of hormone, add it to the known volume of GM, and autoclave to both sterilize and evaporate off any solvent that may have been used to dissolve the often-polar hormones. This hormone/GM solution can be spread across the surface of Petri dishes sown with germinated and/or etiolated seedlings.
@@ Line 101: / Line 103: @@
 Gelidium agar is used primarily for bacteriological plates. Gracilaria agar is used mainly in food applications.
-In 2016, AMAM, a Japanese company, developed a prototype for Agar-based commercial [[Packaging and labeling|packaging]] system called Agar Plasticity, intended as a replacement for oil-based plastic packaging.<ref>{{Cite web|url=https://www.good.is/articles/agar-plasticity-amam-araki-maetani-muraoka-packaging|title=New Seaweed-Based Material Could Replace Plastic Packaging|website=Good Magazine|access-date=2016-04-03|date=2016-03-09}}</ref><ref>{{Cite web|url=http://www.fastcompany.com/3055784/design-award/design-looks-ahead|title=Design Looks Ahead|website=Fast Company|date=26 January 2016|language=en-US|access-date=2016-04-03}}</ref>
+In 2016, AMAM, a Japanese company, developed a prototype for agar-based commercial [[Packaging and labeling|packaging]] system called Agar Plasticity, intended as a replacement for oil-based plastic packaging.<ref>{{Cite web|url=https://www.good.is/articles/agar-plasticity-amam-araki-maetani-muraoka-packaging|title=New Seaweed-Based Material Could Replace Plastic Packaging|website=Good Magazine|access-date=2016-04-03|date=2016-03-09}}</ref><ref>{{Cite web|url=http://www.fastcompany.com/3055784/design-award/design-looks-ahead|title=Design Looks Ahead|website=Fast Company|date=26 January 2016|language=en-US|access-date=2016-04-03}}</ref>
 == See also ==
@@ Line 132: / Line 134: @@
 {{Authority control}}
+[[Category:Dietary fiber]]
 [[Category:Edible thickening agents]]
 [[Category:Microbiological gelling agent]]

Agar: Difference between revisions

Latest revision as of 23:16, 25 May 2026

Contents

Etymology

History

Chemical composition

Physical properties

Uses

Culinary

Asian culinary

Other culinary

Microbiology

Agar plate

Motility assays

Plant biology

Other uses

See also

References

External links

Navigation menu

Agar: Difference between revisions

Latest revision as of 23:16, 25 May 2026

Etymology

History

Chemical composition

Physical properties

Uses

Culinary

Asian culinary

Other culinary

Microbiology

Agar plate

Motility assays

Plant biology

Other uses

See also

References

External links

Navigation menu

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