pectin

pectin
pectinaceous /pek'teuh nay"sheuhs/, pectinous, adj.
/pek"tin/, n. Biochem.
a white, amorphous, colloidal carbohydrate of high molecular weight occurring in ripe fruits, esp. in apples, currants, etc., and used in fruit jellies, pharmaceuticals, and cosmetics for its thickening and emulsifying properties and its ability to solidify to a gel.
[1830-40; < Gk pekt(ós) fixed, congealed (see PECTIC) + -IN2]

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Any of a class of carbohydrates found in certain plant cell walls and tissues.

They are principally composed of a galactose derivative, galacturonic acid. In fruits, pectin keeps the walls of adjacent cells joined together, helping them remain firm and hold their shape. As fruits become overripe, the pectin breaks down to simple sugars that dissolve more readily, so the fruits become soft and lose their shape. Because it forms a thick, gel-like solution when added in small amounts to fruit acids, sugar, and water, pectin is used to make jellies, jams, and marmalades. Its thickening properties also make it useful in the confectionery, pharmaceutical, and textile industries.

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      any of a group of water-soluble carbohydrate substances that are found in the cell walls and intercellular tissues of certain plants. In the fruits of plants, pectin helps keep the walls of adjacent cells joined together. Immature fruits contain the precursor substance protopectin, which is converted to pectin and becomes more water-soluble as ripening proceeds. At this stage the pectin helps ripening fruits to remain firm and retain their shape. As a fruit becomes overripe, the pectin in it is broken down to simple sugars that are completely water-soluble. As a result, the overripe fruit becomes soft and begins to lose its shape.

      Because of its ability to form a thick gel-like solution, pectin is used commercially in the preparation of jellies (jelly), jams, and marmalades. Its thickening properties also make it useful in the confectionery, pharmaceutical, and textile industries. Pectic substances consist of an associated group of polysaccharides (polysaccharide) that are extractable with hot water or with aqueous solutions of dilute acids. The chief sources of commercial pectin are the peels of citrus fruits, and to a lesser extent apple pomace (residue from cider presses). Very small amounts of pectin suffice in the presence of fruit acids and sugar to form a jelly.

      Pectin also has several health benefits in humans. Included among these are its ability to reduce low-density lipoprotein (LDL) levels, thereby lowering cholesterol levels, and its ability to slow the passage of food through the intestine, relieving diarrhea. Pectins can also activate cell death pathways in cancer cells, indicating that pectins may play an important role in preventing certain types of cancer.

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Universalium. 2010.

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  • Pectin — (from Greek πηκτικός pektikos , congealed, curdled [ [http://www.perseus.tufts.edu/cgi bin/ptext?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3D%2382916 Pektikos, Henry George Liddell, Robert Scott, A Greek English Lexicon , at Perseus] ] ), a white …   Wikipedia

  • Pectin — (Pflanzengallerte), C64H40O56 + 8HO, eine dem Pflanzenreich eigenthümliche, im Safte vieler Früchte u. Wurzeln sich findende Substanz (s. Pectinkörper). Nach Frémy enthalten nur reisende u. reife Früchte P.; dasselbe bildet sich aber, wenn… …   Pierer's Universal-Lexikon

  • Pectin — Pec tin, n. [Gr. ? curdled, congealed, from ? to make fast or stiff: cf. F. pectine.] (Chem.) One of a series of carbohydrates, commonly called {vegetable jelly}, found very widely distributed in the vegetable kingdom, especially in ripe fleshy… …   The Collaborative International Dictionary of English

  • pectin — pectin. См. пектин. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • Pectin — Pectin, von Brakanot als derjenige Stoff erkannt, welcher das Gelatiniren der mit Zucker aufgekochten Säfte von Aepfeln, Johannisbeeren, Kirschen etc. bedingt u. wird dargestellt, indem man den Saft fleischiger Früchte bis zum Sieden erhitzt,… …   Herders Conversations-Lexikon

  • pectin- — (var. «pectini ») Elemento prefijo del lat. «pecten, ínis», peine: ‘Pectiniforme’. * * * altpectin , pectini /alt ► Prefijos procedentes del l. pecten, peine …   Enciclopedia Universal

  • pectin — polysaccharide found in fruit and vegetables, crucial in forming jellies and jams, 1838, from Fr. pectine, coined early 1830s by French chemist Henri Braconnot (1781 1855) from acide pectique pectic acid, a constituent of fruit jellies, from Gk.… …   Etymology dictionary

  • pectin — ► NOUN ▪ a soluble jelly like substance present in ripe fruits, used as a setting agent in jams and jellies. ORIGIN from Greek pektos congealed …   English terms dictionary

  • pectin — [pek′tin] n. [< Gr pēktos (see PECTIC) + IN1] a water soluble carbohydrate, obtained from certain ripe fruits, which yields a gel that is the basis of jellies and jams pectinous adj …   English World dictionary

  • Pectin — Pektine (v. griech.: πηκτός pektós = fest, geronnen) sind pflanzliche Polysaccharide, genauer Polyuronide, die im Wesentlichen aus α 1,4 glycosidisch verknüpften D Galacturonsäure Einheiten bestehen. Ernährungsphysiologisch betrachtet sind… …   Deutsch Wikipedia

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