Processing Contaminants in Edible Oils: MCPD and Glycidyl Esters
Edited by Shaun MacMahon
AOCS press, Illinois, 2014
Hardback. $110.00 USD
Amazon electronic version $85.00 USD
Industry, academia and legislators have awaited the publication of a book such as this for quite some time. Heightened awareness around the presence of fatty acid esters of monochloropropanediol in refined edible oils began in 2006 with a publication by Zelinkova.
This book was published following a key seminar to address this issue at an AOCS conference in 2011. The issue attracted intense scrutiny because of its occurrence in infant formulae with the source being the deodorised vegetable oils utilised in the blends.
Compiler and editor, Dr. Shaun MacMahon, is a research chemist with the USFDA.
3-Monochloropropanediol (3-MCPD) esters, 2-monochloropropanediol (2-MCPD) esters and glycidyl esters (GEs) are contaminants that are not present in virgin unrefined oils but can be produced during processing, specifically during high temperature deodorisation.
Where did the chlorine atoms come from?
Analytical methods for contaminants
Management of contaminants
Mitigation strategies that have been used successfully to decrease the concentrations of these contaminants in edible oils are discussed in the second chapter. These include removing precursor molecules before processing, using alkaline additives before deodorising, adding ethanol to the oil, and using selective adsorbents.
The fact that MCPD esters begin forming at temperatures exceeding 200°C makes mitigation difficult because deodorisations with physical refining are generally run at temperatures greater than 200°C.
It is a small oversight, probably due to timing of the compilation, that the book does not have any extra reported work from edible oil practitioners who have experience in changing process conditions to observe changes in contaminant levels. Such work was presented at AOCS seminars in 2012 and 2013 (De Greyt, 2012). Practical economic techniques, suggested by process suppliers such as Desmet, are assisting the edible oil industry in reducing levels to acceptable amounts. This practical work will no doubt be presented at future AOCS conferences and seminars.
The toxicology of glycidyl esters and of the MCPD fatty acid esters is dealt with in two chapters reporting work on the two classes of compound separately. Any toxic effects are due to the products after metabolism in the gut.
Free 3-MCPD and glycidol have been shown to be carcinogenic in rats, with demonstrated effects on kidneys and reproductive systems. Glycidol is well characterised due to its use in the chemical industry. 3-MCPD and glycidol were classified by the European Scientific Committee on Food in 2001 as a non-genotoxic threshold carcinogen. Toxicology is dealt with in a detailed way in the last two chapters of the book by researchers
Areas of interest for the future
Zelinková, Z., B. Svejkovská, J. Velí?ek, and M. Dole?al, Fatty acid esters of 3-chloropropane-1,2-diol in edible oils, Food Addit. Contam. 23:1290?1298 (2006).
Analysis of occurrence of 3-monochloropropane-1,2-diol (3-MCPD) in food in Europe in the years 2009?2011 and preliminary exposure assessment, European Food Safety Authority Journal 11(9):3381 [45 pp.], 2013. http://dx.doi. org/10.2903/j.efsa.2013.3381.
De Greyt, W., How to minimize 3-MCPD- and Glycidyl Esters during Edible Oil Processing, Paper presented to AOCS seminar, Korea, May 11-12th (2012)
AOCS Standard Methods Cd 29a-13 (2- and 3-MCPD fatty acid esters and glycidol fatty acid esters in edible oils and fats by acid transesterification),
Cd 29b-13 Determination of bound monochloropropanediol- (MCPD) and bound 2,3-epoxy-1-propanol (glycidol-) by gas chromatography/mass spectrometry),
Cd 29c-13 (Fatty-acid-bound 3-chloropropane-1,2-diol (3-MCPD) and 2,3-epoxypropane- 1-ol (glycidol), Determination in oils and fats by GC/MS (differential measurement)), 2014.
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Reviewer, Dr Laurence Eyres, FNZIFST, runs his own contracting/consulting business for the Food and Dietary Supplements Industries specialising in dairy, oils and fats and related lipids, product and business development. He has been a member of AOCS since 2002. firstname.lastname@example.org
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