View source for Catechu

{{Short description|Extract of acacia trees}}
{{For|the region in India|Kutch District}}

[[File:Catechu.jpg|thumb|Catechu]]
[[File:Catechu nigrum2.JPG|thumb|right|150 px|Bottle of catechu]]
[[File:Catechu nigrum1.JPG|thumb|left|200 px|Catechu]]

'''<span lang="En" dir="rtl">Catechu</span>''' ({{IPAc-en|ˈ|k|æ|t|ᵻ|ʃ|uː}} or {{IPAc-en|ˈ|k|æ|t|ᵻ|tʃ|uː}})<ref>{{OED|catechu}}</ref> is an extract of acacia trees used variously as a [[food additive]], [[astringent]], [[tannin]], and [[dye]].  It is extracted from several species of [[Acacia sensu lato|Acacia]], but especially ''[[Senegalia catechu]]'' (previously called ''Acacia catechu''), by boiling the wood in water and evaporating the resulting brew.<ref>[http://www.fao.org/docrep/V8879E/v8879e05.htm Cutch and catechu plant origin] {{Webarchive|url=https://web.archive.org/web/20190210133448/http://www.fao.org/docrep/V8879e/V8879e05.htm |date=2019-02-10 }} from the Food and Agriculture Department of the United Nations. Document repository accessed November 5, 2011</ref> The Malay name {{Transliteration|ms|italic=no|'''kachu'''}} is the basis of the Latinized<ref>[http://www.yourdictionary.com/catechu Derivation of word from Malay]</ref> ''catechu'' chosen as the [[Linnaean taxonomy]] name of the plant species which provides the extract.

==Uses==
As an [[astringent]] it has been used since ancient times in [[Ayurvedic medicine]] as well as in breath-freshening spice mixtures—for example in France and Italy it is used in some [[licorice]] [[pastilles]]. It is also an important ingredient in South Asian cooking [[paan]] mixtures, such as ready-made [[paan masala]] and [[gutka]].

The catechu mixture is high in natural vegetable [[tannin]]s (which accounts for its astringent effect), and may be used for the [[Tanning (leather)|tanning]] of animal hides. Early research by [[Humphry Davy]] in the early 19th century first demonstrated the use of catechu in tanning over more expensive and traditional oak extracts.

Under the name ''cutch'', it is a brown dye used for [[Tanning (leather)|tanning]] and dyeing and for preserving [[fishing net]]s and [[sail]]s. Cutch will dye [[wool]], [[silk]], and [[cotton]] a yellowish-brown. Cutch gives gray-browns with an [[iron]] [[mordant]] and olive-browns with a [[copper]] mordant.<ref name="Goodwin (1982)">{{cite book|last=Goodwin|first=Jill|title=A Dyer's Manual|publisher=Pelham Books Ltd.|location=London|year=1982|page=60|isbn=978-0-7207-1327-5}}</ref>

Black catechu has recently also been used by Blavod Drinks Ltd. to dye their [[vodka]] black.<ref>{{cite web|url=https://www.latimes.com/archives/la-xpm-2003-oct-29-fo-black29-story.html|title=They drink this stuff?|date=29 October 2003|work=LA Times|author=Valli Herman|access-date=11 March 2019}} See this reference for the use of the dye in vodka</ref>

[[White cutch]], also known as gambier, gambeer, or gambir, which is extracted from ''[[Uncaria gambir]]''<ref>[http://www.faculty.ucr.edu/~legneref/botany/tandye.htm Tanning, Dye & Processing Materials]</ref> has the same uses. Palm-catechu is extracted from the seeds of ''[[Areca catechu]]''.<ref>Buchheister G.A.: ''Handbuch der Drogisten-Praxis.'' Zweite Auflage, Springer, 1891, p. 322, {{IA|handbuchderdrog02buchgoog|page=337}}.</ref>

== Derivative chemicals ==

The catechu extract gave its name to the [[catechin]] and [[catechol]] chemical families first derived from it. Its historic name is "Japanese Earth" or "Japanese Dirt", which is responsible for naming "[[Japanic acid]]".

==See also==
* [[Arid Forest Research Institute]]

==References==
{{reflist}}

==External links==
{{EB1911 poster|Catechu}}
*[http://www.henriettesherbal.com/eclectic/usdisp/uncaria-gamb.html An OCR'd version of the US Dispensatory by Remington and Wood, 1918.]

{{dyeing}}

[[Category:Plant dyes]]
[[Category:Spices]]
[[Category:Tannins]]