Editing Preservative (section)

===Antioxidants===
[[Image:Lipid peroxidation.svg|thumb|right|The [[Radical (chemistry)|free radical]] pathway for the first phase of the oxidative rancidification of fats.  This process is slowed by antioxidants.]]

The oxidation process spoils most food, especially those with a high fat content.  Fats quickly [[rancidification|turn rancid]] when exposed to oxygen. Antioxidants prevent or inhibit the oxidation process. The most common antioxidant additives are [[ascorbic acid]] ([[vitamin C]]) and ascorbates.<ref name=Bhat/> Thus, antioxidants are commonly added to oils, cheese, and chips.<ref name= Msagati>Msagati, Titus A. M. (2012). The Chemistry of Food Additives and Preservatives. Retrieved from http://www.eblib.com {{Webarchive|url=https://web.archive.org/web/20160207133203/http://www.eblib.com/ |date=2016-02-07 }}</ref> Other antioxidants include the [[phenol]] derivatives [[Butylated hydroxyanisole|BHA]], [[Butylated hydroxytoluene|BHT]], [[tert-Butylhydroquinone|TBHQ]] and [[propyl gallate]].  These agents suppress the formation of hydroperoxides.<ref name="CEN-1" />

{| class="wikitable"
|-
! E number
! chemical compound
! comment
|-
| E300-304
| [[ascorbic acid]], [[sodium ascorbate]]
| cheese, chips
|-
| E321
| [[butylated hydroxytoluene]], [[butylated hydroxyanisole]]
| also used in food packaging
|-
| E310-312
| [[gallic acid]] and sodium gallate
| oxygen scavenger
|-
| E220 – E227
| [[Sulfite food and beverage additives|sulfur dioxide and sulfite]]s
| beverages, wine
|-
| E306 – E309
| [[tocopherol]]s
| vitamin E activity
|-
|}
A variety of agents are added to sequester (deactivate) metal ions that otherwise catalyze the oxidation of fats.  Common sequestering agents are [[EDTA|disodium EDTA]], [[citric acid]] (and citrates), [[tartaric acid]], and [[lecithin]].<ref name=Ullmann/>