Quantification of monomeric cyclic fatty acids

A urea adduction step to concentrate CFAMs was introduced so that stearate was removed and low levels of CFAMs, encountered in many samples, could be analysed (Potteau, 1976). However, this approach had 

In short, it is now clear that a successful method requires a hydrogenation step, followed by a concentration step and finally a GC analysis of CFAMs. Polar columns such as CP-Sil 84 (Chrompack, Middelburg, The Netherlands) and BPX70 (SGE, Milton Keynes, UK) are the best choice because hydrogenated CFAMs are more clearly resolved from stearate than on less polar columns such as Carbowax (Sebedio, 1985). The troublesome step is the concentration of CFAMs. Ideally, a method should allow recovery of all CFAMs and totally exclude saturated fatty acids, particularly stearate, and other impurities which may interfere with subsequent GC. 

The method appears to offer relative accuracy, sensitivity and speed of analysis over previous methods, but it would be of interest to test its robustness with a variety of samples, including vegetable oils. Although the procedure is applicable to CFAMs from sunflower and linseed oils. 

Total hydrogenated fatty acid methyl esters 

In an industrial operation for production of pre-fried french fries using palm oil, the HPLC method was used to show that total CFAMs present increased from 0.02% (formed during deodorization) in the starting oil to a maximum of 0.08% and 0.10% in the oil and french fries, respectively 

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