Editing Bread (section)

===Sourdough===
{{Main|Sourdough}}
[[File:Sour dough loaves03.jpg|thumb|Sourdough loaves]]

Sourdough is a type of bread produced by a long fermentation of dough using naturally occurring yeasts and [[Lactobacillus|lactobacilli]]. It usually has a mildly sour taste because of the [[lactic acid]] produced during [[Anaerobic respiration|anaerobic]] [[fermentation]] by the lactobacilli. Longer fermented sourdoughs can also contain [[acetic acid]], the main non-water component of vinegar.<ref name=DavidsonSourdough>{{cite book | first=Alan | last=Davidson | year=1999 | title=The Oxford Companion to Food | publisher=Oxford University Press | isbn=978-0-19-211579-9 | pages=[https://archive.org/details/oxfordcompaniont00davi_0/page/756 756–57] | url=https://archive.org/details/oxfordcompaniont00davi_0/page/756 }}</ref><ref>{{cite book | editor1=Gobbetti, Marco |editor2=Gänzle, Michael |date=2012 |title=Handbook on Sourdough Biotechnology |publisher=Springer |isbn=978-1-4899-9189-8}}</ref><ref>{{Cite journal |last=Ng |first=Henry |date=June 1972 |title=Factors Affecting Organic Acid Production by Sourdough (San Francisco) Bacteria |journal=Applied Microbiology |language=en |volume=23 |issue=6 |pages=1153–1159 |doi=10.1128/am.23.6.1153-1159.1972 |issn=0003-6919 |pmc=   380523 |pmid=5042265}}</ref>

Sourdough breads are made with a sourdough starter. The starter cultivates yeast and lactobacilli in a mixture of flour and water, making use of the microorganisms already present on flour; it does not need any added yeast. A starter may be maintained indefinitely by regular additions of flour and water. Some bakers have starters many generations old, which are said to have a special taste or texture.<ref name=DavidsonSourdough/> At one time, all yeast-leavened breads were sourdoughs. Recently there has been a revival of sourdough bread in artisan bakeries.<ref>{{cite news|last1=Mesure|first1=Susie|title=Supermarkets cash in on sourdough bread craze as popularity surges |url=https://www.independent.co.uk/life-style/food-and-drink/news/supermarkets-cash-in-on-sourdough-bread-craze-as-popularity-surges-a6844101.html |newspaper=[[The Independent]] |access-date=2 October 2016|date=30 January 2016}}</ref>

Traditionally, peasant families throughout Europe baked on a fixed schedule, perhaps once a week. The starter was saved from the previous week's dough. The starter was mixed with the new ingredients, the dough was left to rise, and then a piece of it was saved to be the starter for next week's bread.<ref name=BAC/>