Class of astringent, bitter plant polyphenolic chemical compounds
For the mythical creature, see Tannin (monster).
Not to be confused with Tanin (disambiguation).
Representative chemical structure of a tannic acid, a type of tanninTannin powder (mixture of compounds)A bottle of tannic acid solution in water
Tannins (or tannoids) are a class of astringent, polyphenolic biomolecules that bind to and precipitate proteins and various other organic compounds including amino acids and alkaloids.
The term tannin (from Anglo-Norman tanner, from Medieval Latin tannāre, from tannum, oak bark) refers to the use of oak and other bark in tanning animal hides into leather. By extension, the term tannin is widely applied to any large polyphenolic compound containing sufficient hydroxyls and other suitable groups (such as carboxyls) to form strong complexes with various macromolecules.
The tannin compounds are widely distributed in many species of plants, where they play a role in protection from predation (acting as pesticides) and might help in regulating plant growth.[1] The astringency from the tannins is what causes the dry and puckery feeling in the mouth following the consumption of unripened fruit, red wine or tea.[2] Likewise, the destruction or modification of tannins with time plays an important role when determining harvesting times.
Tannins have molecular weights ranging from 500 to over 3,000[3] (gallic acid esters) and up to 20,000 daltons (proanthocyanidins).
^Ferrell, Katie E.; Thorington, Richard W. (2006). Squirrels: the animal answer guide. Baltimore: Johns Hopkins University Press. p. 91. ISBN 978-0-8018-8402-3.
^McGee, Harold (2004). On food and cooking: the science and lore of the kitchen. New York: Scribner. p. 714. ISBN 978-0-684-80001-1.
^Bate-Smith and Swain (1962). "Flavonoid compounds". In Florkin M.; Mason H. S (eds.). Comparative biochemistry. Vol. III. New York: Academic Press. pp. 75–809.
Tannins (or tannoids) are a class of astringent, polyphenolic biomolecules that bind to and precipitate proteins and various other organic compounds including...
A hydrolysable tannin or pyrogallol-type tannin is a type of tannin that, on heating with hydrochloric or sulfuric acids, yields gallic or ellagic acids...
from the Great Sandy National Park to Tin Can Bay stained with tea-tree tannin. Other rivers in Australia may experience infrequent 'blackwater events'...
condensed tannins. Quebracho tannin is also sold as an enological tannin. The quebracho tannins structure is very similar to that of grape tannins, making...
Tannic acid is a specific form of tannin, a type of polyphenol. Its weak acidity (pKa around 6) is due to the numerous phenol groups in the structure....
flavonoids and non-flavonoids. Flavonoids include the anthocyanins and tannins which contribute to the color and mouthfeel of the wine. The non-flavonoids...
Procyanidins are members of the proanthocyanidin (or condensed tannins) class of flavonoids. They are oligomeric compounds, formed from catechin and epicatechin...
many different species of plants. Tannins are separated into two classes: hydrolysable tannins and condensed tannins. Depending on their concentration...
and mouthfeel of tea. Polyphenols in tea include catechins, theaflavins, tannins, and flavonoids. Polyphenols found in green tea include, but are not limited...
types of hydrolysable tannins. Specifically, tannase catalyzes the hydrolysis of ester and depside bonds of hydrolysable tannins to release glucose and...
widely grown. The fruit has a high tannin content, which makes the unripe fruit astringent and bitter. The tannin levels are reduced as the fruit matures...
phloroglucinol connected by esters (hydrolyzable tannins) or more stable C-C bonds (nonhydrolyzable condensed tannins). Proanthocyanidins are mostly polymeric...
or thorny shrub native to Peru. T. spinosa is cultivated as a source of tannins based on a galloylated quinic acid structure. This chemical structure has...
solubility of their tannin and the presence of seeds. Soluble tannin means that the fruit will have an acrid taste. Insoluble tannin means that there is...
profile of Cabernet Sauvignon tends to be full-bodied wines with high tannins and noticeable acidity that contributes to the wine's aging potential....
with other nuts. Acorns also contain bitter tannins, the amount varying with the species. Since tannins, which are plant polyphenols, interfere with...
liquor. Some common types include: Vegetable-tanned leather is tanned using tannins extracted from vegetable matter, such as tree bark prepared in bark mills...
cider apples in 1903 into four main types according to the proportion of tannins and malic acid in the fruit. For cider production, it is important that...
wine with white wine. White and rosé wines extract little of the grape tannins contained in the skins. To start primary fermentation, yeast may be added...
Daniel Tammet FRSA (born Daniel Paul Corney; 31 January 1979) is an English writer and savant. His memoir, Born on a Blue Day (2006), is about his early...
large number of pests and diseases. Oak leaves and acorns contain enough tannin to be toxic to cattle, but pigs are able to digest them safely. Oak timber...
from Quercus infectoria contain the highest naturally occurring level of tannin, approximately 50–70%, as well as syringic acid, β-sitosterol, amentoflavone...
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