Editing Propionic acid (section)

==Industrial uses==
Propionic acid inhibits the growth of [[Mold (fungus)|mold]] and some bacteria at levels between 0.1 and 1% by weight.  As a result, some propionic acid produced is consumed as a [[preservative]] for both animal feed and food for human consumption. For animal feed, it is used either directly or as its [[ammonium]] salt. This application accounts for about half of the world production of propionic acid. The antibiotic [[monensin]] is added to cattle feed to favor [[Propionibacterium|propionibacteria]] over acetic acid producers in the [[rumen]]; this produces less carbon dioxide and feed conversion is better. Another major application is as a preservative in baked goods, which use the [[sodium]] and [[calcium]] salts.<ref name=Ullmann/> As a [[food additive]], it is approved for use in the EU,<ref>{{cite web | url = http://www.food.gov.uk/safereating/chemsafe/additivesbranch/enumberlist | title = Current EU approved additives and their E Numbers | publisher = UK Food Standards Agency | access-date=27 October 2011 }}</ref> US,<ref>{{ cite web | url = https://www.fda.gov/Food/FoodIngredientsPackaging/FoodAdditives/ucm191033.htm#ftnT | archive-url = https://web.archive.org/web/20100108135705/http://www.fda.gov/Food/FoodIngredientsPackaging/FoodAdditives/ucm191033.htm#ftnT | url-status = dead | archive-date = 8 January 2010 | title = Listing of Food Additives Status Part II | publisher = US Food and Drug Administration | access-date=27 October 2011 }}</ref> Australia and New Zealand.<ref>{{cite web | url = http://www.comlaw.gov.au/Details/F2011C00827 | title = Standard 1.2.4 – Labelling of ingredients | work = Australia New Zealand Food Standards Code | date = 8 September 2011 | publisher = Comlaw.au | access-date=27 October 2011 }}</ref>

Propionic acid is also useful as an intermediate in the production of other chemicals, especially polymers. [[Cellulose acetate|Cellulose-acetate-propionate]] is a useful [[thermoplastic]].  [[Vinyl propionate]] is also used.  In more specialized applications, it is also used to make [[pesticide]]s and [[pharmaceutical]]s.  The [[ester]]s of propionic acid have fruit-like odors and are sometimes used as [[solvent]]s or artificial flavorings.<ref name=Ullmann/>

In [[biogas plants]], propionic acid is a common intermediate product, which is formed by fermentation with propionic acid bacteria. Its degradation in anaerobic environments (e.g. biogas plants) requires the activity of complex microbial communities.<ref name="Ahlert">{{cite journal|last1 = Ahlert|first1 = Stephan|last2 = Zimmermann|first2 = Rita|last3 = Ebling|first3 = Johannes|last4 = König|first4 = Helmut|year = 2016|title = Analysis of propionate-degrading consortia from agricultural biogas plants|journal = MicrobiologyOpen |doi = 10.1002/mbo3.386|pmid = 27364538|pmc = 5221444|doi-access = free|volume = 5|issue = 6|pages = 1027–1037}}</ref>

In production of the [[Jarlsberg cheese]], a propionic acid bacterium is used to give both taste and holes.<ref>[https://www.jarlsberg.com/articles/qa www.jarlsberg.com] quote: " In the production of Jarlsberg®, propionic acid bacteria (the Secret Recipe!) is used to give the cheese its characteristic taste and holes."</ref>