Bo Pils Techniques

Minimize DMS

120 minute boil or vigorous 60 min boil(2)
Chill as quickly as possible – don’t allow to stand at high, but not boiling temp(2)
Lower wort pH results in less DMS
Do some head space purging in the keg

Large starter
Non-pressurized fermentation during vigorous (or even the entire) fermentation – allow as much CO2 to come out of solution as possible (1, 2)
Increase fermentation temp from 50f after a week or two to 65f for a week or two to reduce DMS/diacetyl (2)
Do not stir yeast in starter to reduce DMS (2)
I’ve never been able to replicate the caramel undertones of a Pilsner Urchell. I’ve tried concentrating first runnings, adding malts like melanoidin, munich, vienna and carahell, and even decoction mashing. Nothing I’ve done with my brews has replicated the particular flavour I’m seeking. More and more, I’m lead to the conclusion that the flavour is a combination of diacetyl (from czech yeast) and oxidation (in a beer made half-way around the world, months before I consume it). For most lagers I’ve been drawn to the cleaner yeasts, like 2124, but I think using a czech yeast like 2000, 2001, or 2002, in combination with an extended lagering might do the trick. That is, if I can let the beer have an extended lagering period.

It pains me, but the results of my first triple decoction have made [non-scientifically] conclude that doing a decoction serves both to improve the malty flavours and bring out a golden hue to the final beer – book an entire day for this brew. Or… maybe it was just in my head (Brulosophy is not so sure – 5, 6).

Use a light hand when building the recipe:
- 94% Pilsner, 3% Munich, 3% Acidulated to 4.5% ABV + 18IBU from Sterling/Saaz + Wyeast 2124 = pretty damn good beer
- Do not go over the top with specialty malts – the closer to 100% pilsner malt, the better.
- I really like a good hoppy beer. Bo pils is not a good hoppy beer. Something about late Saaz hops (in quantity) is objectionable. I’ve been happiest with my lightest-flavour/aroma-hopped batches.

As a thirsty homebrewer, sometimes it takes a while for techniques to sink in (or down, to use a more accurate preposition). Letting a bo pils “chill” in the keg for a while really helps the harsh, intense flavour hops to mellow and the beer to clear all the more. My last batch has been lagering in the keg at 36f for about eight weeks now, and it’s much better than it was when it first went in. Too bad the keg is three-quarters finished now. Must learn to defer [for greater] enjoyment.

Filter with activated carbon filter to remove chlorine and chloramines (or use RO water)
Lower mash pH with 3% acid malt (4)
Re-harden water with 1g CaCl/5 gal water and 0.5g CaSO4/5 gal water

Always got better feedback on filtered beer – especially these light-coloured ones. Besides improving the experience of ‘drinking with the eyes’, I think the yeast itself can have flavours that throw off the ‘cleanliness’ of the beer.
While filtering can produce a very clear beer quickly, I’ve found using gelatin fining almost effective and a lot less mess and hassle. I’ve had good luck with Brulosophy’s technique (7)…
- After beer comes to terminal gravity, chill to 0celcius
- For each five gallon fermentor, combine 1/2tsp unflavoured gelatin in 1/4cup water
- Microwave in seven second intervals until the solution reaches 145F, stirring with a thermometer between microwaving
- Add to the fermentor and leave for a few days
- Rack the beer off the sediment into serving kegs