Alpha Acid %
13.5 – 16%
Admiral was originally intended to replace Wye Target as a high alpha acid hop variety used for bittering. It didn’t really take hold in the way it was intended primarily because of it’s perceptibility to disease. It’s parents are the Challenger and Northdown varieties.(citation)
Admiral is used primarily as a bittering hop primarily because of the alpha levels and also the aroma is quite mild so it complements other varieties in beers nicely without competing. I have seen it described as both pleasant and English in aroma which usually brings to mind the grassy and spicy qualities of Fuggles and East Kent Goldings. As it was bred as a replacement to Target it is less harsh than it’s predecessor in terms of flavour and aroma.
Admiral are an English hop and are used mainly in English style beers like Pale ales and Bitters.
As they were bred in particular as a replacement for Target it is worth looking to these hops as a possible substitution. Target are a great hop in their own right but they are of slightly lower alpha acid levels so you will need to adjust your recipe accordingly..
I have found next to no beers that solely use Admiral hops there is one released very recently, whether you can get hold of it though is another thing. Adnams have recently released a beer available right now on cask only called English Red http://adnams.co.uk/beer/our-beers/english-red-ale/ of course finding this one is going to be a challenge for most people.
More famously Three Floyds Brewing make a Blackheart English IPA that use Admiral as a bittering hop and at around 80 IBU you’re gonna get a fair whack of them.
I expect a lot of British breweries use them as a bittering hop in some of their beers. If you know of any drop a line