Journal of the American Oil Chemists' Society

, Volume 86, Issue 9, pp 843–856 | Cite as

A Comprehensive Evaluation of the Melting Points of Fatty Acids and Esters Determined by Differential Scanning Calorimetry

  • Gerhard KnotheEmail author
  • Robert O. Dunn
Original Paper


The melting point is one of the most important physical properties of a chemical compound and it plays a significant role in determining possible applications. For fatty acid esters the melting point is essential for a variety of food and non-food applications, the latter including biodiesel and its cold-flow properties. In this work, the melting points of fatty acids and esters (methyl, ethyl, propyl, butyl) in the C8–C24 range were determined by differential scanning calorimetry (DSC), many of which for the first time. Data for triacylglycerols as well as ricinoleic acid and its methyl and ethyl esters were also acquired. For some compounds whose melting points have been previously reported, data discrepancies exist and a comprehensive determination by DSC has not been available. Variations in the present data up to several °C compared to data in prior literature were observed. The melting points of some methyl-branched iso- and anteiso-acids and esters were also determined. Previously unreported systematic effects of compound structure on melting point are presented, including those for ω-9 monounsaturated fatty acids and esters as well as for methyl-branched iso and anteiso fatty acids and esters. The melting point of a pure fatty acid or ester as determined by DSC can vary up to approximately 1 °C. Other thermal data, including heat flow and melting onset temperatures are briefly discussed.


Fatty acids Differential scanning calorimetry Butyl esters Ethyl esters Melting point Methyl esters Propyl esters 



The authors thank Kevin Steidley, Erin Walter and Kim Ascherl for excellent technical assistance in obtaining the data used in this work and Dr. Karl Vermillion for obtaining the NMR spectra.


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Copyright information

© AOCS 2009

Authors and Affiliations

  1. 1.US Department of Agriculture, Agricultural Research ServiceNational Center for Agricultural Utilization ResearchPeoriaUSA

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