Chromatography Forum

Hello,
I am attempting to fractionate margarine by solid phase extraction to run on HPLC but I am having a problem with the water. Is anyone else analyzing margarine? (Cholesterol, Fatty Acid, Triglyceride) Can you let me know how you get rid of the water? Or even how you deal with it. Is anyone doing this or have done it is the past??
Thank you,
Ann Lucas

My lab would use GC for those three assays.

Although I agree GC is a better method for this stuff, I did these analysis some time ago by HPLC.

For free fatty acids, I did a simple solvent extraction and inject in a Phenyl column, using isopropanol and water as mobile phase.

For triglycerides, I did it by SEC using a TSKgel Linear column.

For these methods you need a RI detector, that is tricky and not very sensitive.

I hope this helps you initial work. If you need any further help, just post!

We have done these by GC in the past, and there was a lot of interference and the peaks were distorted. Also, the margarine sort of dovetails with another project I am doing, so we thought we'd try to separate the lipids by SPE and see what happens. I am in the process of a trial run right now. I wanted to know anyone else's experience so I could work with what was good for them and avoid some pitfalls.
Thanks for the help!
Ann