A Tool For Picking Bourbon Barrels: The Birectifier Method

Clay Risen in the New York Times just wrote an interesting article about the Napa-fication of Kentucky. He profiles Dixon Dedman and the creation of the allegedly cult Kentucky Owl brand.

One thing that stuck out in the article was that Mr. Dedman had some trouble selecting his initial barrels and turned to Jim Rutledge for help. Rutledge rejected the first round of barrels. This struck a chord because I just spoke to a friend about selecting Bourbon barrels and possibly further aging them on location at his unique Michelin style property.

The big question: is there any tool that may help select quality barrels and possibly teach the grammar of blending? What about without the help of an oracle like Jim Rutledge?

Why yes, it is the birectifier, and you don’t need to know much chemistry to use it. You may not have heard of it because it is from the 1930’s and the design has been lost since the 1950’s.


The birectifier is special, first and foremost because it is affordable, at a fraction of the price of chromatography. You can also learn to operate it in an afternoon while chromatography often is PhD only. The birectifier can isolate and highlight the highest value congeners that only special optimized (university only) forms of chromatography can. In many practical ways, the birectifier beats the state of the art.

The birectifier is like a stethoscope, scalpel, and magnifying glass for spirits. It allows you to carve away the noise and magnify what you want to look at. It also allows very consistent operation so comparisons made can be faithful.

To pick a bourbon barrel, you want to consider five variables:

  • How much ethyl acetate is there?
  • How much fusel oil is there?
  • How strong is the High Value Congener fraction?
  • How much noble volatile acidity is there?
  • How much non-volatile barrel extract is in the stillage?

The birectifier cuts a spirit into 8 standardized fractions so you can faithfully compare them across barrels. The first two fractions describe the ethyl acetate content, the forth fraction describes the fusel oil content, the fifth fraction is the High Value Congener fraction, and the last fractions (6,7,8) contain both noble volatile acidity and possible flaws.

Many of these variables can fluctuate barrel to barrel because of the rhythms of production. Not all barrels can stand alone and many have to be averaged by blending. It takes tremendous experience to taste samples alone and make sound comprehensive pronouncements. The birectifier is both a crutch and a method of building intuition. Quality can be learned by deconstructing exemplary role models. Is Van Winkle your role model? Study it!

  • Ethyl acetate, the most ordinary congener,  flatters other in a range. It typically either needs averaged down by blending or more time to accumulate during maturation. An immature American whiskey will have below average ethyl acetate. Some funky distillates may have too much.
  • Fusel oil also must not be excessive. It does not leave with the angel’s share so much as react to form new products. It often has to be averaged to hit an ideal.
  • Seeking out High Value Congeners is at the heart of picking barrels from within large stocks. These congeners are either in the ester family (best associated with rum) or derived from carotenoids present in the grains. The highest value congeners are present at extremely low levels, but are aromatic enough to define spirit quality. These are the Ionones and β-Damascenone. They have unique properties in their own right, but are some time called radiants and participate with others to form more complex percepts.
  • Noble volatile acids helps give a spirit structure so it does not seem flabby. It fluctuates with fermentation time (72 or 96 hours?) as lactic acid bacteria accumulates in vats and thus varies barrel to barrel (across broader lots).
  • Stillage, left over after distillation of the sample, can be dehydrated to measure (weigh) the barrel solids. There is a sweet spot. Too much and a spirit can be overly woody which many extra aged spirits are accused of. Too little and a spirit is flabby and unstructured.

As a blend takes shape, unique barrels can be picked to help average out the components, filling in voids. Blends can come together the traditional way via extensive systematic trials vatted in graduated cylinders, but they can also be tested with the birectifier to make progress more evident and more paint by numbers. Any insights you have on barrels before blending will strengthen your hand going into the process. It will not be voodoo, it will simply be the grammar of harmony.

If you’re new to barrel picking and maturation monitoring, the birectifier is the it tool. Feel free to contact me privately with any questions.

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