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===Cyanogenic Glycosides===
All plants contain at least tiny amounts of [https://en.wikipedia.org/wiki/Hydrogen_cyanide hydrogen cyanide] ('''HCN'''), however some plants also release high amounts of HCN from a class of glycosides called "cyanogenic glycosides", also called "cyanoglycosides". [https://en.wikipedia.org/wiki/Amygdalin Amygdalin] and [https://en.wikipedia.org/wiki/Linamarin linamarin] are common examples of cyanogenic glycosides <ref name="Gleadow_2014"></ref>. HCN is released from cyanogenic glycosides just like other types of glycosides: beta-glucosidase enzyme or exposure to low pH breaks the bond between a glucose molecule and an unstable compound called "cyanohydrin" (or "alpha-hydroxynnitrile"), which then disassociates into a ketone or benzaldehyde and an HCN molecule. In cyanogenic glycosides, this reaction is called "cyanogenesis". Cyanogenesis is stimulated by maceration, and by bacteria in the human gut <ref name="Speijers">[http://www.inchem.org/documents/jecfa/jecmono/v30je18.htm "Cyanogenic Glycosides", First Draft. Dr G. Speijers. National Institute of Public Health and Environmental Protection Laboratory for Toxicology, Bilthoven, The Netherlands. Retrieved 08/25/2016.]</ref>. Although the optimum pH of cyanogenesis (at least for amygdalin) is 5.0 - 5.8, cyongenesis can occur at a wide range of pH values, and can occur in the presence of acid <ref>[http://www.sciencedirect.com/science/article/pii/S0308814601003132 Total cyanide determination of plants and foods using the picrate and acid hydrolysis methods. M Rezaul Haque, J Howard Bradbury. 2002.]</ref>. If seeds containing cyanogenic glycosides are ground up, the coarseness to which they are ground effects how quickly cyanogenesis occurs. Finely ground seeds extract HCN within an hour, where as coarsely ground seeds extract within 24 hours <ref name="tuncel">[http://www.sciencedirect.com/science/article/pii/030881469599841M The effects of grinding, soaking and cooking on the degradation of amygdalin of bitter apricot seeds. G Tunçel, M.J.R Nout, L Brimer. 1995.]</ref>. HCN boils at a relatively low temperature (25.6°C / 78.1°F) <ref name="Gleadow_2014"></ref>. In some cases, soaking, cooking, and/or sometimes fermenting foods with certain bacteria or yeast (this has not been fully documented with ''Saccharomyces'' or ''Brettanomyces'') that contain cyanogenic glycosides allows the HCN to be released, and then subsequent cooking afterwards will boil off the cyanide <ref>[http://www.sciencedirect.com/science/article/pii/016816059400115M International Journal of Food Microbiology. M.J.R. Nout, G. Tunçe, L. Brimer. 1995.]</ref><ref name="Chaouali"></ref>.