Thursday, February 15, 2007

SPME of my beer

Finally, I am getting around to posting about the SPME (solid-phase microextraction) I did of one of my beers. SPME is pretty sweet. It involves dipping a fiber coated with what is usually on the inside of a GC column. Clever Canadian. The fiber is then placed in the GC/MS inlet port at about 300°C for 3 minutes. Any analytes are desorbed and sent to the MS detector via the 30m GC column (I can't remember what type of column I used).

In this case I used a fiber coated with 75μm of a carboxen/polydimethylsiloxane. The beer I chose was my second attempt at cloning Fat Tire Belgian Ale. A 4 mL sample was acidified to pH=2 and the fiber was placed in the sample while stirring for 15 minutes. The GC/MS trace is shown below:



I'd love to tell you what all of the peaks are, but you are going to have to wait until tomorrow. I have the list, but I'm tired and am going to bed.....

2 comments:

MJenks said...

Any true analytical chemist worth his hops would get an authentic sample of Fat Tire to shoot through the machine. AND, if I remember correctly, you'll be getting Fat Tire soon enough to sample.

Lucky duck...

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