fermentation

American  

[fur-men-tey-shuhn] / ˌfɜr mɛnˈteɪ ʃən /

noun

1. the act or process of fermenting.

2. a change brought about by a ferment, as yeast enzymes, which convert grape sugar into ethyl alcohol.

3. agitation; excitement.

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fermentation British  

/ ˌfɜːmɛnˈteɪʃən /

noun

1. Also called: ferment.  a chemical reaction in which a ferment causes an organic molecule to split into simpler substances, esp the anaerobic conversion of sugar to ethyl alcohol by yeast

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fermentation Scientific  

/ fûr′mĕn-tā′shən /

1. The process by which complex organic compounds, such as glucose, are broken down by the action of enzymes into simpler compounds without the use of oxygen. Fermentation results in the production of energy in the form of two ATP molecules, and produces less energy than the aerobic process of cellular respiration. The other end products of fermentation differ depending on the organism. In many bacteria, fungi, protists, and animals cells (notably muscle cells in the body), fermentation produces lactic acid and lactate, carbon dioxide, and water. In yeast and most plant cells, fermentation produces ethyl alcohol, carbon dioxide, and water.

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fermentation Cultural  

1. A chemical reaction in which sugars are broken down into smaller molecules that can be used in living systems. Alcoholic beverages, such as beer, wine, and whiskey, are made from the controlled use of fermentation. Fermentation is an anaerobic process.

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Other Word Forms

• fermentativeness
  noun
• nonfermentation
  noun
• prefermentation
  noun
• self-fermentation
  noun
• fermentative
  adjective
• fermentatively
  adverb

Etymology

Origin of fermentation

First recorded in 1350–1400; Middle English fermentacioun, from Late Latin fermentātiōn-, stem of fermentātiō, from Latin fermentāt(us) “fermented” (past participle of fermentāre “to ferment”; see ferment) + -iō -ion

Explanation

Fermentation is the process in which a substance breaks down into a simpler substance. Microorganisms like yeast and bacteria usually play a role in the fermentation process, creating beer, wine, bread, kimchi, yogurt and other foods. Fermentation comes from the Latin word fermentare, meaning “to leaven.” To make bread rise, you use a leavening agent to “wake up” dry yeast by mixing it with water. The yeast then starts “eating” the sugar in the dough and off-gassing alcohol: that’s fermentation. Grape juice becomes wine as the fermentation process is complete.

Example Sentences

Fermentation is a biological process whereby organisms convert carbohydrates like starch or sugar into substances like alcohol, without using oxygen.

From BBC • Jun. 4, 2026

The yearly Portland Fermentation Festival, also known as “Stinkfest,” used to have more amateurs exhibiting their wares.

From The Wall Street Journal • Nov. 11, 2025

Fermentation offers a chance to learn how taste and heritage shape microbiomes: not only of culturally significant foods such as German sauerkraut, kosher pickles, Korean kimchi or Bulgarian yogurt, but of our own guts.

From Salon • Apr. 17, 2024

Fermentation is a relatively easy preservation technique that has been used for thousands of years.

From Seattle Times • Dec. 13, 2023

Fermentation of organic matter goes on when there is a certain amount of alkalinity present; while, on the other hand, the presence of acidity seems to retard and check it.

From Manures and the principles of manuring by Aikman, Charles Morton