So I half chickened out and decided to do a potato pale ale.
The recipe was very simple, 3kg Lager malt, 2 kg potatoes, 10g of Summit as first wort hops, and 20g Northern Brewer at flame out. The yeast was to be a Scottish Ale yeast, though fermentation temperature was a concern given I still have no decent temperature control.
I started by boiling the washed potatoes (skin and all) in 6 liters of water for 30 minutes. I then blended the potatoes, adding 3 liters of cold water in the process, before adding the grain. The mash was then at 55°C, and I brought it slowly up to 60°C over the next half hour. I then ramped up the heat and added 4 more liters of 85°C water to get the mash quickly to 67°C. I mashed until iodine test showed full conversion.
However it was obvious I was going to suffer from the stuck mash from hell, so I brought the entire mash to just under boiling temps, before doing my first sparge (decoction mashes have taught me that boiling the mash while all the sugars are present doesn’t add any noticeable tannin extraction). Interestingly after this, the iodine test was black, showing much unconverted starch. With all the enzymes destroyed I had no choice but to sparge anyway.
The sparging process was so painful that I ended stopping the sparging early. I could have added water to the boil kettle to get volumes up, but decided at that point to go for a stronger beer. From this point on the brew was relatively straightforward, with the only concern being a sudden hot spell that ramped the fermentation from 21-22°C in the first 2 days up to 24-26°C thereafter.
The beer was drinkable straight out of the fermenter, but the tasting notes are from 3 weeks in the bottle.
Aroma: Red berries overpowering the northern brewer hops, minty aromas that dominated at bottling time all but gone now. Warming brings out an earthiness behind the berry. Is that potato skin or hop?
Flavour: Fruity berry flavours dominate with light malt and just the hint of potato bringing up the rear. Sweet, but a strong bitterness at the end makes this very drinkable. Warming starts to bring out a bit more of a piney/earthy hop flavour, but those red berries continue to dominate.
Mouthfeel: High body, thick on the tongue with a low prickly carbonation helping keep the palate dry.
Conclusion: I will be doing this beer again. It’s tasty, has a lot of body, and many interesting flavours. The next batch will definitely need some attention to the mash, with an acid rest and separate decoction of the potatoes and a portion of the malt.
14 Liters of beer into the fermenter