August 6, 2013- Buffalo Trace’s experimental Single Oak Project is looking for the proof with the tenth batch in the four-year-long project.

Each batch so far has tested the difference key variables make in the development of a Bourbon’s aroma and flavor, by tweaking some variables while keeping others the same. The 192 expressions to be released in quarterly batches of 12 were aged for identical lengths of time in barrels made from half of a single tree — with one barrel coming from the bottom half and one from the top. The other variables include the mash bill (rye or wheat), entry proof, warehouse location, the size of the grain and the length of seasoning time for the barrel staves, and the level of charring in the barrel.

Batch #10′s unique variable was entry proof, with the wheat and rye mash bills being filled into the barrels at either 125 proof (62.5% ABV, the maximum allowed under U.S. law for Bourbon) or 105 proof (52.5% ABV). All other variables remained the same, allowing consumers to see whether a noticeable difference can be found. Other Buffalo Trace experiments have found that a higher entry proof can often lead to higher evaporation rates. However, all expressions in the Single Oak Project series are bottled at 45% ABV.

The distillery has been seeking feedback from consumers on their preferences after tasting many of the 108 bottles previously released in the series. Voting and tasting notes entered at the Single Oak Project web site now show a new leader in the clubhouse, with Barrel #59 as the favorite after a long run for Barrel #106. The eventual goal will be to take the final winner after the project ends in 2015 and replicate it under the Single Oak brand name.

Links: Buffalo Trace