I enjoyed this for the first time last night (on cask!) which prompted me learn more about it. There are two questions which I could use help with. The pump handle mentioned "first fill sherry casks." Does the distiller use first fill sherry casks? Also, these are the specs from Harviestoun's website: Tech spec BASE BEER Old Engine Oil brewed to 10.5% abv BOTTLED at 8% abv HOPS Galena, East Kent Goldings, Fuggles ABV 8% in bottle, 10.5% in cask and keg IBU 40 Aged for up to 6 months in casks that formerly held Highland Park 12 Year Old Single Malt Whisky How does the base beer at 10.5% become an 8% beer in the bottle? Is it blended with regular Old Engine Oil? I'm also curious to hear if anyone has compared the bottle and cask/keg versions? I imagine they must taste very different. Thanks in advance for any help! Oh, and anyone in the Lancaster PA vicinity should get to the Bulls Head in Lititz to try this!
Without knowing for sure, I'd speculate that: The first fill sherry casks are those from the distiller that were originally sherry casks and used once for aging Highland Park 12. Those casks then then wound up at the brewer for aging the Old Engin Oil as it turned into the the Ola Dubh. From the wording on the web site I'd conclude that the Old Engine Oil that started aging in the casks was brewed to be 10.5% and then the resulting Ola Dubh was "adjusted" (with water) after aging to be bottled at 8%. Edit: As for the keg, cask versions of Ola Dubh, any change from the base beer would have been to see an increase in ABV and so it was probably also "adjusted" before kegging and/or putting in cask.
