Wednesday, December 20, 2006

NMR and Whisky

I have a real weakness for single malt whisky so when I started my PhD in Cambridge I was pleasantly surprised to see that the NMR machines were named after Scotch single malt whiskies: Aberlour, Cragganmore, Glengrant, Glenlivet and Laphroaig. At the same time as I started my PhD they began the process of acquiring and installing a 700 MHz Bruker Cryo probe monster. Obviously this new addition to the collection of NMR machines needed a name. I'm a big fan of the Arran single malt whisky which at the time was the youngest Scottish distillery. So I thought that Arran would be an appropriate name for the departments youngest NMR machine and I suggested it to the NMR guys. I even went as far as purchasing them a little box with a selection of Arran malts. Clearly, the guys liked the idea and to my great pleasure the machine was named Arran. Here's a picture of the NMR people (from left: Duncan, Andrew and Brian) with Arran and a selection of miniature Arran bottles:

Not only do they give their NMR machines great names but they also provide a most excellent NMR service. These guys actually like what they do and will go to great lengths to help you out. The best NMR department (by orders of magnitude) that I have experienced so far. Anyway, after Arran was named we obviously had to run some 1 and 2D NMR of the Arran malt on Arran to see what the spectrum of a tasty single malt looks like. Below the HMQC spectrum of the organic phase after an extraction of Arran malt with dichloromethane is shown. We didn't use the regular stuff but a limited edition single cask Arran malt (Bottle no. 125 of 348, 58.7%, distilled 18/7-1997).

Yes a complete waste of time and resources but it was fun. We took the photo above and a bunch of the NMR spectra and sent it to Isle of Arran Distillers with a letter explaining matters and it turned out that the guys at the distillery really liked the story. They showed their appreciation by sending us a bottle of Arran malt each - nice guys! D!

12 comments:

Ψ*Ψ said...

cool! No more wasteful than an earwax NMR, either (which was also pretty cool).

Luke said...

Earwax?!? Eww!

Dare I ask how clean that turned out? The arran was cleaner than I expected.

milkshake said...

Japanese have done some extensive NMR and GC/MS research on identification of flavor components of single malts. Despite of all this research , their artificialy-flavored nipponese scotch brands stil taste like murder.

Another practical application of this kind of research is the flavoring in butterscotch-pudding and egg nog. It contains a mysterious substance called whisky lactone :) and i think this one actualy comes from oak barrels rather then peat-smoked malt.

There was a paper in Org Lett about 2 years ago about taking NMR 1-H spectra without lock and among the samples they run was also bourbon whiskey. I think they were using their NMR method as an assay for determining alcohol content in liquers.

Ψ*Ψ said...

The earwax appeared in Tenderbutton--you can find it in the archives. ;)

Anonymous said...

Note: There's almost no reason to use HMQC anymore. The HSQC is a much cleaner sequence which does the same job, and multiplets along f2 appear with much nicer in-phase lineshapes.

Daniel Sejer said...

Yo Milkshake, there's nothing mysterious about Whisky lactone aka Oak lactone aka (4S,5S)- and (4S,5R)-5-butyl-4-methyl-4,5-dihydro-2(3H)-furanone except for how it's generated during the oak maturation process. A whole range of different precursors have been suggested, in particular ring opened version that are glycosylated or acylated on the secondary alcohol. Of the two Oak lactone isomers the (4S,5S)-isomer is considered the more important from a sensory point of view. It is believed to be one of the compounds that impart coconut- and vanilla-like nuances to wine. It can be purchased in buckets and is used widely in the manufacture of cheap scotch whiskies to improve the taste (it still tastes like shite in my opinion). By the way the blended japanese whiskies do indeed make you blind and throw up. However, the Japanese make awesome single malt whiskies that go very well with sushi. The only problem is that they are very expensive compared to their scottish counterparts. D!

Daniel Sejer said...

Errrmmmm HSQC which is? I'd better know what the abbreviations stands for before I ask my NMR guy to run one of these babies. D!

Tom said...

Hey D don't forget your boss ran a project to make Oak lactone Org. Lett. 2006 pg 463 from the all powerful 1,2-dioxine :)

Zebra said...

Whisky is not one of my favourite but naming NMR machine Arran is not a bad idea. And you got a few free bottles so it was worth the efforts!

TotallyMedicinal said...

You would have been better off calling an NMR machine Macallan_18yo. Now that is something special and well worth the extra!

Can totally agree with the sentiments on the Cambridge NMR team (seeing as I did my PhD there!) - top blokes, top quality instruments, top quality service.

Nonjatta said...

"Despite of all this research , their artificialy-flavored nipponese scotch brands stil taste like murder."
You might want to revise that stereotype now that the Japanese are winning some of the top whisky awards internationally.

Daniel Sejer said...

There is no denying that the Japanese (and many others) make great single malt. However, the Japanese stuff is very expensive compared to the Scoth stuff. D!