Lactic acid | Fermentation, Metabolism, Energy

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Lactic Acid in Food: Good or Bad?</a></li> <li><a class="external" href="https://www.academia.edu/19574545/Lactic_acid_applications_in_Pharmaceutical_and_Cosmeceutical_Industries_A_critical_review" target="_blank" rel="noopener ">Academia - Lactic acid applications in Pharmaceutical and Cosmeceutical Industries: A critical review.</a></li> <li><a class="external" href="https://pubchem.ncbi.nlm.nih.gov/compound/Lactic-acid" target="_blank" rel="noopener ">National Center for Biotechnology Information - PubChem - Lactic Acid</a></li> <li><a class="external" href="https://www.livescience.com/what-is-lactic-acid" target="_blank" rel="noopener ">LiveScience - What is lactic acid?</a></li> <li><a class="external" href="https://www.verywellhealth.com/lactic-acid-7092705" target="_blank" rel="noopener ">Verywell Health - What is Lactic Acid?</a></li> <li><a class="external" href="https://www.pnas.org/doi/10.1073/pnas.98.2.395" target="_blank" rel="noopener ">PNAS - Lactic acid: New roles in a new millennium</a></li> <li><a class="external" href="https://cameochemicals.noaa.gov/chemical/8774" target="_blank" rel="noopener ">CAMEO Chemicals - Lactic Acid</a></li> <li><a class="external" href="https://www.ijert.org/research/lactic-acid-production-using-food-waste-IJERTV6IS050608.pdf" target="_blank" rel="noopener ">International Journal of Engineering Research and Technology - Lactic Acid Production using Food Waste</a></li> <li><a class="external" href="https://www.webmd.com/fitness-exercise/exercise-and-lactic-acidosis" target="_blank" rel="noopener ">WebMD - Lactic Acidosis and Exercise: What You Need to Know</a></li> <li><a class="external" href="https://www.khanacademy.org/science/biology/cellular-respiration-and-fermentation/variations-on-cellular-respiration/v/lactic-acid-fermentation" target="_blank" rel="noopener ">Khan Academy - Lactic acid fermentation</a></li> <li><a class="external" href="https://www.bbc.co.uk/bitesize/topics/zvrrd2p/articles/ztdmrwx" target="_blank" rel="noopener ">BBC Bitesize - Lactic Acid</a></li> <li><a class="external" href="https://www.fao.org/fileadmin/user_upload/jecfa_additives/docs/Monograph1/Additive-247.pdf" target="_blank" rel="noopener ">Food and Agricultutre Organisation of the United Nations - Lactic acid</a></li> <li><a class="external" href="https://my.clevelandclinic.org/health/body/24521-lactic-acid" target="_blank" rel="noopener ">Cleveland Clinic - Lactic Acid</a></li> <li><a class="external" href="https://www.cell.com/heliyon/fulltext/S2405-8440(20)31817-X" target="_blank" rel="noopener ">Cell Press - Heliyon - Lactic acid production – producing microorganisms and substrates sources-state of art</a></li> </ul> </div> </div> </div> </div> </div> <div class="toc-header-marker"></div> <button class="ai-ask-button btn border-2 js-header-ai-ask-button d-none btn-sm btn-outline-red-400 border-red-400 mr-0 mr-lg-10 ml-5 ml-sm-10 ml-lg-0 p-10"> Ask the Chatbot a Question </button> <div class="caption alternate-titles">Also known as: α-hydroxypropionic acid, 2-hydroxypropanoic acid, 2-hydroxypropionic acid, alpha-hydroxypropionic acid</div> <div class="md-byline module-spacing "> <div class="font-serif font-12"> <span class="written-by text-gray-700"> Written and fact-checked by </span> <div class="editor-popover popover p-0"> <a class="d-block p-20 qa-editor-popup gtm-byline font-12 byline-contributor" href="/editor/The-Editors-of-Encyclopaedia-Britannica/4419" > <div class="editor-title font-16 font-weight-bold">The Editors of Encyclopaedia Britannica</div> <div class="editor-description font-12 font-serif mt-5 text-black">Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors.</div> </a> <div data-popper-arrow></div> </div> <span class="btn btn-link editor-link p-0 qa-byline-link gtm-byline font-12 byline-contributor text-decoration-underline"> The Editors of Encyclopaedia Britannica</span></div> <div class="last-updated font-12 font-serif"> <span class="text-gray-700"> Last Updated: <time datetime="2025-01-03T00:00:00CST" >Jan 3, 2025</time> •</span> <a class="byline-edit-history" href="https://www.britannica.com/science/lactic-acid/additional-info#history" rel="nofollow">Article History</a> </div></div> </div> <button class="d-flex d-lg-none btn btn-outline-blue border rounded-sm shadow-sm mobile-toc-button gtm-mobile-toc-inline-button d-none d-sm-block js-sections-inline-button module-spacing btn d-lg-none"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="toc"></em> Table of Contents </button> <div class="d-flex d-sm-none flex-row"> <button class="d-flex d-lg-none btn btn-outline-blue border rounded-sm shadow-sm mobile-toc-button gtm-mobile-toc-inline-button js-sections-inline-button module-spacing"> <em class="material-icons mr-5 ml-n10 my-n5 md-icon" data-icon="toc"></em> Table of Contents </button> <button class="ai-ask-button btn border-2 ai-ask-button btn border-2 module-spacing btn-sm js-inline-ai-ask-button btn-outline-red-400 border-red-400 p-10 ml-5"> Ask the Chatbot a Question </button> </div> <div class="js-qf-module qf-module px-40 px-sm-20 py-15 mx-auto module-spacing font-14 bg-gray-50 rounded"> <div class="facts-list mt-10"> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Also called: </dt> <dd>α-hydroxypropionic acid, or 2-hydroxypropanoic acid</dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> </div> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Key People: </dt> <dd><a href="/biography/Johannes-Adolph-Wislicenus" topicid="645968">Johannes Wislicenus</a></dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> </div> <div class=""> <div class="js-fact mb-10 line-clamp clamp-3"> <dl> <dt>Related Topics: </dt> <dd><a href="/science/lactic-acid-bacterium" topicid="327364">lactic-acid bacterium</a></dd> <dd><a href="/science/hydroxy-acid" topicid="279111">hydroxy acid</a></dd> </dl> <button class="js-more-btn d-none btn btn-unstyled font-12 bg-gray-50" aria-label="Toggle more/less fact data"> <em class="js-content link-blue">(Show more)</em> </button> </div> <div class="text-center"> <a class="btn btn-sm btn-link p-0" href="/facts/lactic-acid"> See all related content </a> </div> </div> </div> </div><span class="marker before-article"></span><section data-level="1" id="ref1"><span class="marker PREMOD1 mod-inline"></span><p class="topic-paragraph"><strong><span id="ref87274"></span>lactic acid</strong>, an <a href="https://www.britannica.com/science/organic-compound" class="md-crosslink autoxref " data-show-preview="true">organic compound</a> belonging to the family of carboxylic acids, present in certain plant juices, in the <a href="https://www.britannica.com/science/blood-biochemistry" class="md-crosslink autoxref " data-show-preview="true">blood</a> and muscles of animals, and in the soil. It is the commonest acidic <a class="md-dictionary-link md-dictionary-tt-off mw" data-term="constituent" href="https://www.merriam-webster.com/dictionary/constituent" data-type="MW">constituent</a> of fermented <a href="https://www.britannica.com/topic/milk" class="md-crosslink autoxref " data-show-preview="true">milk</a> products such as sour milk, cheese, and buttermilk.</p><span class="marker MOD1 mod-inline"></span><span class="marker PREMOD2 mod-inline"></span><p class="topic-paragraph">First isolated in 1780 by a Swedish chemist, <span id="ref87275"></span><a href="https://www.britannica.com/biography/Carl-Wilhelm-Scheele" class="md-crosslink " data-show-preview="true">Carl Wilhelm Scheele</a>, lactic acid is manufactured by the fermentation of molasses, starch, or whey in the presence of alkaline substances such as lime or calcium carbonate; it is available as aqueous solutions of various concentrations, usually 22–85 percent, and degrees of purity. Lactic acid is used in tanning leather and dyeing wool; as a flavouring agent and preservative in processed cheese, salad dressings, pickles, and carbonated beverages; and as a raw material or a <a class="md-dictionary-link md-dictionary-tt-off mw" data-term="catalyst" href="https://www.merriam-webster.com/dictionary/catalyst" data-type="MW">catalyst</a> in numerous chemical processes. Pure lactic acid, rarely prepared, is a colourless, crystalline substance that melts at 18° C (64° F); it rapidly absorbs moisture from the atmosphere.</p><div class="one-good-fact-module"> </div><span class="marker MOD2 mod-inline"></span><span class="marker PREMOD3 mod-inline"></span><p class="topic-paragraph">Lactic acid occurs in the blood (in the form of its salts, called <span id="ref87276"></span><a href="https://www.britannica.com/science/lactate" class="md-crosslink ">lactates</a>) when <a href="https://www.britannica.com/science/glycogen" class="md-crosslink autoxref " data-show-preview="true">glycogen</a> is broken down in <a href="https://www.britannica.com/science/muscle" class="md-crosslink autoxref " data-show-preview="true">muscle</a> and can be converted back to glycogen in the liver. Lactates are also the products of <a href="https://www.britannica.com/science/fermentation" class="md-crosslink " data-show-preview="true">fermentation</a> (<em>q.v.</em>) in certain bacteria.</p><div class="module-spacing"> </div><span class="marker MOD3 mod-inline"></span></section> <span class="md-signature">This article was most recently revised and updated by <a href="/editor/Amy-Tikkanen/6393">Amy Tikkanen</a>.</span><span class="marker end-of-content"></span><span class="marker after-article"></span></div> <div id="chatbot-root"></div> </div> </div> </div> <div class="ai-dialog-placeholder"></div> </div> </div> <aside class="col-md-da-320"></aside> </div> </div> </div> </div> </article> </div> </div> </div> </div> </main> <div id="md-footer"></div> <noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-5W6NC8" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript> <script type="text/javascript" id="_informizely_script_tag"> var IzWidget = IzWidget || {}; (function (d) { var scriptElement = d.createElement('script'); scriptElement.type = 'text/javascript'; scriptElement.async = true; scriptElement.src = "https://insitez.blob.core.windows.net/site/f780f33e-a610-4ac2-af81-3eb184037547.js"; var node = d.getElementById('_informizely_script_tag'); node.parentNode.insertBefore(scriptElement, node); } )(document); </script>  <script> window.ap3c = window.ap3c || {}; var ap3c = window.ap3c; ap3c.cmd = ap3c.cmd || []; ap3c.cmd.push(function() { ap3c.init('ZO4siT4cLwnykPnzZWJtd3Byb2Q', 'https://engage.email.britannica.com/'); ap3c.track({v: 0}); }); ap3c.activity = function(act) { ap3c.act = (ap3c.act || []); ap3c.act.push(act); }; var s, t; s = document.createElement('script'); s.type = 'text/javascript'; s.src = "https://engage.email.britannica.com/app.js"; t = document.getElementsByTagName('script')[0]; t.parentNode.insertBefore(s, t); </script> <script class="marketing-page-info" type="application/json"> {"pageType":"Topic","templateName":"DESKTOP","pageNumber":1,"pagesTotal":1,"pageId":327346,"pageLength":199,"initialLoad":true,"lastPageOfScroll":false} </script> <script class="marketing-content-info" type="application/json"> [] </script> <script src="https://cdn.britannica.com/mendel-resources/3-133/js/libs/jquery-3.5.0.min.js?v=3.133.9"></script> <script type="text/javascript" data-type="Init Mendel Code Splitting"> (function() { $.ajax({ dataType: 'script', cache: true, url: 'https://cdn.britannica.com/mendel-resources/3-133/dist/topic-page.js?v=3.133.9' }); })(); </script> <script class="analytics-metadata" type="application/json"> {"leg":"D","adLeg":"C","userType":"ANONYMOUS","pageType":"Topic","pageSubtype":null,"articleTemplateType":"SMALL","gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":true} </script> <script type="text/javascript"> EBStat={accountId:-1,hostnameOverride:'webstats.eb.com',domain:'www.britannica.com', json:''}; </script> <script type="text/javascript"> ( function() { $.ajax( { dataType: 'script', cache: true, url: '//www.britannica.com/webstats/mendelstats.js?v=1' } ) .done( function() { try {writeStat(null,EBStat);} catch(err){} } ); })(); </script> <div id="bc-fixed-dialogue"></div> </body> </html>

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Lactic acid | Fermentation, Metabolism, Energy | Britannica