For those who haven’t had the chance to brew a Baltic porter before it is a fantastic beer to test several aspects of your brewing expertise. A cross between a traditional British Porter, with some aspects of an Imperial Russian Stout but all brewed with lager yeast at lager temperatures. It’s a full-bodied and flavoursome, dark beer but with a clean fermentation profile that can prove quite tricky to get right.
Originally, as a result of brown malts being wood fire kilned, Baltic porters would have some smoky character but as ingredients manufacturing has changed this is no longer a required characteristic of the style. Instead, you should be aiming for a complex, malty character – full of sweet toffee, caramel, nutty flavours, liquorice and chocolate without (or at least with less of) the roast, burnt or coffee flavour you would normally expect in a big stout.
These are big beers as well, typically coming in between 7 and 10% ABV which can often present its own problems. You need to make sure that you are pitching enough yeast to ensure off flavours aren’t created by the yeast becoming stressed during fermentation and also you will need to be able to control fermentation temperatures to allow the lager yeast to ferment at the ideal temperature but also to prevent issues with higher (or fusel) alcohol formation which can make the beer ‘hot’ when you drink it. An unpleasant sensation that can plague high ABV beers. You want a pleasant warming sensation from the alcohol, not a throat burning sensation.
So how do you go about brewing them?
Firstly, look at the malt bill. You want a lot of character coming through here so start with a large quantity of characterful base malt and then compliment it with Vienna and/or Munich to get that solid malt base. Remember, this is a big, malty beer so don’t be afraid to use a lot of malt here. Next, you should add chocolate or black malt. Around 10% should be plenty to give you a great colour and some rich flavour contributions. Porters are typically not as dark as stouts, tending to be more on the ‘brown’ scale rather than opaque black.
With these malts as your base, you can begin to add the rest of your malt – these should be additions that are going to add to the malt complexity and the overall flavour profile that you are aiming for so things like caramel/crystal malts, amber malts or caramunich. Keep the total of these additions at less than 10% to avoid any overpowering flavours or cloying sweetness.
To balance the big malt character you should be looking for an IBU rating of between 20-40 IBU’s. Try to get your BU:GU ratio around the 45 mark to ensure you are balancing the sweetness of the malts properly. You don’t want your beer to end up cloyingly sweet and undrinkable! As for which hops to use, noble hops work well to give a rich but subtle earthy character that compliments the malt complexity in an understated way.
For your water there is no need to do anything too clever, just be aware that the dark malts will acidify your mash so make sure you are still within your optimal mash PH range (5.2 – 5.5). It is also worth noting that carbonates help to mellow the harshness that dark malts can impart so you may choose to increase the carbonates in your water profile to give a smoother overall taste.
Finally, your yeast. Baltic porters are brewed in much the same way as a lager so choose a clean lager strain and make sure you are pitching plenty of yeast because not only does this beer ferment cold but it is a high ABV beer as well – both of which mean fermentation needs a bit more care. This will also take longer than most beers to fully ferment so be patient – you can get great results from a Baltic porter if you are willing to wait.
The last note is to mash high to create a more full-bodied final beer. This style is one of our personal favourites when it is brewed right and if it’s not something you’ve brewed yourself then it is definitely worth a go.
The recipe below is for a large grain bill (8.8kgs or 19lbs) so for best results we would recommend mashing in half your grains into your full amount of water and stirring extremely thoroughly, ensuring grain is completely soaked and there are no clumps. Add your recirculation arm and recirculate for 5 minutes. Take your recirculation arm off, add another 1kg (2.2 lbs) and stir thoroughly. Repeat the process of 5 minutes recirculation, adding 1kg of grain (2.2lbs) and stirring until you have added your complete grain bill. I would also recommend reducing your mash water to 2.3 litres per kg rather than 2.7 litres (0.6 US Gallons per 2.2 lbs). It’s a bit more work to mash in this way but it will help you reduce the efficiency hit that typically comes with brewing a large grain bill on any kit. For best results, take the top plate off and stir the mash thoroughly every 15-20 minutes as well.