Editing Sodium nitrite (section)

=== Occurrence in vegetables ===
Nitrites do not occur naturally in vegetables in significant quantities,<ref name="Dennis & Wilson 2003 Nitrates and Nitrites">{{cite book |doi=10.1016/B0-12-227055-X/00830-0 |chapter=Nitrates and Nitrites |title=Encyclopedia of Food Sciences and Nutrition |year=2003 |vauthors=Dennis MJ, Wilson LA |pages=4136–4141 |isbn=978-0-12-227055-0}}</ref> but deliberate fermentation of [[celery|celery juice]], for instance, with a naturally high level of nitrates, can produce nitrite levels sufficient for commercial meat curing.<ref>{{cite web |title=Is celery juice a viable alternative to nitrites in cured meats? |url=https://www.mcgill.ca/oss/article/food/celery-juice-viable-alternative-nitrites-cured-meats |access-date=14 September 2022 |website=Office for Science and Society |language=en}}</ref> Boiling vegetables does not affect nitrite levels.<ref name="Leszczyńska">{{cite journal |vauthors=Leszczyńska T, Filipiak-Florkiewicz A, Cieślik E, Sikora E, Pisulewski PM |date=June 2009|title=Effects of some processing methods on nitrate and nitrite changes in cruciferous vegetables |journal=Journal of Food Composition and Analysis |volume=22 |issue=4 |pages=315–321 |doi=10.1016/j.jfca.2008.10.025}}</ref>

The presence of nitrite in animal tissue is a consequence of metabolism of [[nitric oxide]], an important neurotransmitter.<ref>{{cite journal | vauthors = Meulemans A, Delsenne F | title = Measurement of nitrite and nitrate levels in biological samples by capillary electrophoresis | journal = Journal of Chromatography. B, Biomedical Applications | volume = 660 | issue = 2 | pages = 401–404 | date = October 1994 | pmid = 7866533 | doi = 10.1016/0378-4347(94)00310-6}}</ref> Nitric oxide can be created ''[[wiktionary:de novo|de novo]]'' from [[nitric oxide synthase]] utilizing [[arginine]] or from ingested nitrite.<ref>{{cite journal | vauthors = Southan GJ, Srinivasan A | title = Nitrogen oxides and hydroxyguanidines: formation of donors of nitric and nitrous oxides and possible relevance to nitrous oxide formation by nitric oxide synthase | journal = Nitric Oxide | volume = 2 | issue = 4 | pages = 270–286 | date = August 1998 | pmid = 9851368 | doi = 10.1006/niox.1998.0187}}</ref>