Skip to main content
ARS Home » Research » Publications at this Location » Publication #57253


item Knothe, Gerhard - Gary
item Lie Ken Jie M S
item Lam C C
item Bagby, Marvin

Submitted to: Chemistry and Physics of Lipids
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/30/1995
Publication Date: N/A
Citation: N/A

Interpretive Summary: Fats and oils and their partially hydrogenated products, such as animal fats, tallow and seed oils like soybean, sunflower, rapeseed, consist of fatty acids of many structures. Scientists and technologists need to better understand the composition of the materials with which they work. One structural characteristic of fatty acids important to the scientist and technologist, working to develop value added industrial or food products, is the location of the unsaturation present in the mono- and polyunsaturated acids. Mathematical equations were developed that provide an improved and simplified procedure to determine position of unsaturation by using magnetic resonance data. This method provides a rapid approach to analyzing complex mixtures of fatty acids contained in fats and oils.

Technical Abstract: The 13C-NMR signals of the unsaturated carbons in triacylglycerols with monoenoic and monoynoic chains were evaluated as rational functions. Corresponding to previous results on fatty acids and esters, the signals of the ethylenic carbons are proportional to the negative third power of the position of the unsaturation in the chain. The signals of the acetylenic carbons are proportional to the negative second power of the position of the unsaturation. The POSE (position of shift equivalence) of the unsaturated carbons is more remote from C1 for triacylglycerols than for free fatty acids and esters.