Sample prep procedures for poultry fat

[jm72761]

Currently using GPC sample prep for cleanup to analyze chc pesticides. unit i have can only run 1 sample at a time. Looking to change to new method that will allow me to cleanup multiple samples. Considering using florisil column, any help to get me started would be appreciated.

[James_Ball]

I was working on this for some time also. I found a few ideas that seemed to work.

Extract with Acetonitrile, then freeze the samples to allow most of the lipids to fall out of solution. Then you can use Fluorsil or Alumina cartridges to remove the lipids.

I found an application at Phenomenex using their cleanup cartridges but when I followed it exactly I still had too much lipid remaining and it would cause loss of sensitivity after a couple samples, but once I did the extraction in Acetonitrile and froze the samples it would handle the lipid loading.

[Rndirk]

Isn't saponification required as a first step to get apolar analytes out of fatty matrices?

[James_Ball]

Isn't saponification required as a first step to get apolar analytes out of fatty matrices?

The CHC method from the FDA simply lists a hexane extraction then passing through a GPC to remove the lipids, the analyte list isn't very large and recoveries are listed as being decent. We didn't have the GPC so I searched and found the application from Phenomenex, but I had to modify it for the turkey fat samples we had before I could remove all the lipid material. Of course I moved to another higher priority project before I could completely tweak the method, but hope to return to it later.

[Rndirk]

Isn't saponification required as a first step to get apolar analytes out of fatty matrices?

The CHC method from the FDA simply lists a hexane extraction then passing through a GPC to remove the lipids, the analyte list isn't very large and recoveries are listed as being decent. We didn't have the GPC so I searched and found the application from Phenomenex, but I had to modify it for the turkey fat samples we had before I could remove all the lipid material. Of course I moved to another higher priority project before I could completely tweak the method, but hope to return to it later.

You're right, GPC is an alternative way to get stuff out of fat.

[Consumer Products Guy]

Extract with Acetonitrile, then freeze the samples to allow most of the lipids to fall out of solution.

We used similar technique, maybe with methanol as well.

[MSCHemist]

I tend to use 96% ethanol from the local liquor store to extract flavor compounds from vegetable oils. The lipids larger than glycerol tricaprate fall out of solution though neobee (c8-c10 lipids) stays in but that can be eluted from the gc column. practically all flavor compounds are readily soluble in ethanol. I haven't tried methanol or acetonitrile yet. ACN is expensive and methanol may be too polar for some of my compounds.

[James_Ball]

I tend to use 96% ethanol from the local liquor store to extract flavor compounds from vegetable oils. The lipids larger than glycerol tricaprate fall out of solution though neobee (c8-c10 lipids) stays in but that can be eluted from the gc column. practically all flavor compounds are readily soluble in ethanol. I haven't tried methanol or acetonitrile yet. ACN is expensive and methanol may be too polar for some of my compounds.

I have used the same ethanol for several extractions. I just make sure to keep it hid well under the bench