lactic acid


Definition of lactic acid

: a hygroscopic organic acid C3H6O3 present normally especially in muscle tissue as a by-product of anaerobic glycolysis, produced in carbohydrate matter usually by bacterial fermentation, and used especially in food and medicine and in industry

Examples of lactic acid in a Sentence

Recent Examples on the Web The buttery taste that’s found in many Chardonnays is usually a result of malolactic fermentation, a process in which a wine’s tart malic acid is converted into creamy lactic acid. Esther Mobley,, "Should JaM Cellars be allowed to monopolize buttery Chardonnay?," 24 Apr. 2020 The anode is a nanocomposite material that contains an enzyme that breaks down lactic acid. Wei Gao, The Conversation, "A smart second skin gets all the power it needs from sweat," 22 Apr. 2020 In addition to the volcanic sand used as the physical exfoliant, the formula also contains glycolic and lactic acids. Marci Robin, Allure, "Halle Berry Revealed Her Favorite Face Scrub, and It's Under $30," 21 Mar. 2020 The two most popular AHAs are glycolic and lactic acids. Amber Katz, SELF, "Chemical Exfoliation Is the Skin-Care Step Your Body Is Missing," 9 Aug. 2018 The starch in the flour thickens the soup, and the acids — acetic and lactic acids produced through fermentation— add a note of sourness. Nik Sharma,, "A Brown Kitchen: A recipe for bean soup that uses sourdough starter," 24 Apr. 2020 If your skin is congested, perhaps try exfoliating acids such as glycolic and lactic acid instead. Rhea Cartwright,, "Is Skin Care Still Necessary If You’re Almost Always Indoors?," 7 Apr. 2020 The active ingredients in most peels are alpha or beta hydroxy acids, namely glycolic and lactic acid, which are chemical exfoliants. Jenn Sinrich, SELF, "10 Easy and Effective Chemical Peels You Can Do at Home," 24 Mar. 2020 Steinmetz uses malolactic fermentation, in which the tart apple taste (malic acid) is converted to softer tasting (lactic acid). Kathy Flanigan, Milwaukee Journal Sentinel, "Dry hard ciders used to be the rage in Wisconsin. A new cider maker wants to bring that back," 17 Mar. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'lactic acid.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of lactic acid

1790, in the meaning defined above

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The first known use of lactic acid was in 1790

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Last Updated

8 Jun 2020

Cite this Entry

“Lactic acid.” Dictionary, Merriam-Webster, Accessed 5 Jul. 2020.

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More Definitions for lactic acid

lactic acid


English Language Learners Definition of lactic acid

technical : a chemical produced by the body in your muscles during exercise

lactic acid


Medical Definition of lactic acid

: a hygroscopic organic acid C3H6O3 that is known in three optically isomeric forms:
a or D-lactic acid \ ˈdē-​ How to pronounce D-lactic acid (audio) \ : the dextrorotatory form present normally in blood and muscle tissue as a product of the anaerobic metabolism of glucose and glycogen
b or L-lactic acid \ ˈel-​ How to pronounce L-lactic acid (audio) \ : the levorotatory form obtained by biological fermentation of sucrose
c or DL-lactic acid \ ˈdē-​ˈel-​ How to pronounce DL-lactic acid (audio) \ : the racemic form present in food products and made usually by bacterial fermentation (as of whey or raw sugar) but also synthetically, and used chiefly in foods and beverages, in medicine, in tanning and dyeing, and in making esters for use as solvents and plasticizers

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Spanish Central: Translation of lactic acid

Nglish: Translation of lactic acid for Spanish Speakers Encyclopedia article about lactic acid

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