Appearance: Pours extremely foamy out of the cask, resulting in a big glass of perfect white foam that slowly unveils the predictable yellow beer. Once the beer settles it presents a straw yellow beer with a lasting white head. The head doesn't do a great job of creating lacing on the glass but it lasts down to the very last sip. Light carbonation creates a minimal amount of bubbles along the bottom and sides of the glass. Clarity is not great for a lager and moderate for an ale. This would be a huge flaw for a lager that should feature brilliant clarity but produced in the keller style it was not fully lagered, which leaves some of the powdery lager yeast in suspension. The aggressive early pours from the cask also kick up some of the yeast and add to the moderately cloudy appearance.
Aroma: The beer has a gentle mix of aromas but you can smell them coming out of the glass. Hop aroma hits you first. I opted not to go the traditional saaz hop route and it is obvious. There is the expected spicy/herbal Saaz-like aromas but they are wrapped up in Aurora's complex fruity and floral character. Lime, pineapple, mango and passionfruit appear but with greater restraint than the fruity flavors of American or southern hemisphere hops. The lime character is pleasantly milder than Styrian Celeia, which is all lime all the time. There is also a gentle floral aroma. A nice sort of American/Czech blend of character that reminds me of the IPLs floating around. Under the hops appears the grain with notes of straw, cracker, bread crust and a hint of white grape.
Flavor: While the aroma tells you the beer is going to punch you with hops, the grain hits you first. It is more grainy than the typical BoPils (due to using American pilsner malt) but not offensively so. Grain, hay, white bread, bread crust, cracker, slight caramel and toffee notes. Then comes the hops with a flavor that matches the aroma. As the beer warms the lime fades and the spicy notes become more evident. While the beer is smooth up front, as the hop flavor hits there is also a distinct bitterness that balances the beer and presents a lasting bitterness that lingers after swallowing. Slight fruity esters appear in the middle of the flavor expression. It's pleasantly gentle and helps smooth the transition from grain to hop flavors. It's not the smooth perfection of a lagered pilsner but the flavor has a nice rustic element to it that makes it obviously a BoPils but also obviously something different than the norm.
Mouthfeel: Light but not watery. Early into the pour the creamy head gives the beer more body and a very smooth, creamy feel. As the head reaches a more moderate tone the light carbonation becomes more obvious and it develops a more expected lager mouthfeel. Not quite as crisp as the usual pilsner but definitely not as heavy on the tongue as an ale. The lingering bitterness gives the feeling of cleansing the palette and preparing you for the next gulp.
Overall: Really happy with this beer. It's not a traditional BoPils by any means but it delivers exactly what it should. A crisp and light beer with a fairly robust flavor that makes it a great summer beer when I'm not in the mood for the usual saison or sour. It's exactly what I envisioned. The party pig cask packaging has turned out fantastic. It gives the beer a little more body and mellows the bitterness but did not give the beer the heaviness of cask ale. Good stuff.
I really like this beer and would be very happy to rebrew it exactly the same way. I do miss some of the saaz character in a BoPils and I would like to try both a more traditional hop profile and blending Aurora with Saaz to bring out more of the herbal side of hops. This beer would fail in competition as a BoPils with the undoubted comments that it should be lagered more and styled as an IPL but within the unbound terms of keller style it is justifiably labeled a BoPils with an unconventional hop choice. It's probably too hoppy for a BoPils but I'm not concerned with fitting into style guidelines as much as I am about making delicious beer. And I have.
If I wanted to bottle this beer with the normal carbonation level I would reduce the IBUs slightly to account for the bitterness accentuation brought by a higher level of carbonation. However, I am so happy with the party pig (maybe even more than using it with ales) that other than bottling a bottle or two to share with people out of the house I don't see a reason not to use the party pig. I definitely see more kellerbier in my future.