Yogurt
food produced by bacterial fermentation of milk
Yogurt (UK: ; US: ; also spelled yoghurt, yogourt or yoghourt) is a food produced by bacterial fermentation of milk. The bacteria ferment the sugars in the milk and produce lactic acid, which acts on milk protein to give yogurt its texture and characteristic tart flavor. Yogurt is most commonly made from cow's milk, but milk from water buffalo, goats, ewes, mares, camels, and yaks can also be used.
The main bacteria used to produce yogurt are Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus. Other lactobacilli and bifidobacteria are sometimes added during or after culturing yogurt. Some countries require yogurt to contain a specific amount of colony-forming units (CFU) of bacteria; for example, in China, the requirement for the number of lactobacillus bacteria is at least 1 million CFU per milliliter. Some countries also regulate which bacteria can be used: for example, in France, a product can only be labeled as yaourt or yoghourt if it has been fermented exclusively by Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus, a requirement that aligns with the international definition of yogurt in the Codex Alimentarius on fermented milk (CXS 243-2003).
The bacterial culture is mixed in, and a warm temperature of 30–45 °C (86–113 °F) is maintained for 4 to 12 hours to allow fermentation to occur, with the higher temperatures working faster but risking a lumpy texture or whey separation.
The public source identifies “Yogurt” as food produced by bacterial fermentation of milk. This brief keeps that definition visible, then builds a research path around Yogurt, food and produced.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 18, 2026. The linked authority identifier is Q13317. The Library of Congress control number is sh85149192. 1 of 1 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 2003.
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This entry incorporates text from “Yogurt” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.