I want to make a smoked porter from a porter recipe that I found. To make it a smoked porter, do I just swap a certain amount of base malt with a rauchmalt? Pardon my ignorance–I don’t do recipe formulation.
Welcome to the forum!
Depending on the batch size and the level of smoked flavor, it could be between a quarter pound and a couple pounds. Porter stands up well to as much as 2 pounds in a 5.5 gallon batch, but that is pushing it on my palate.
Remember that smoked malts lose smokiness due to age and out gassing. If it is highly smokey go on the low end, not much smoke go on the high end.
Some of us smoke our own grains to get the level we desire.
As hopfenundmalz says a lot depends on the freshness of the rauchmalt, and on how smoky you want your beer. If you want a hint of smoke add a pound of rauchmalt to your recipe. If you want “bottled bacon” replace 30-50% of your base malt with rauchmalt. And I smoke my own grains but it’s still hard to get a consistent smoke level. Freshness is easy to control, the smoke level of home smoked malt is harder to control from one batch to another.
Yes, just sub out some of the 2 row with some smoked malt of your choice. As ynotbrusum says, it will depend on your tolerance of smoke level how much smoked malt you add. I’ve gone as far as 50% of the grain bill before (smoked myself over apple wood - very smoky).
Also as was mentioned, older rauchmalt might not be very smoky. Because of that I prefer to smoke my own malt. It’s not too difficult. I have a small square frame with a screen I built that fits on my smoker. It can handle about a pound at a time but it only takes 10-15 minutes or so to get it plenty smoky so doing several pounds in an hour or two is no problem.
About a year and a half ago I found some old rauchmalt in my fridge that was at the time probably a couple years old. Only the hint of stale smoke was present. I ended up tossing it on the smoker with some other grains to smoke but that smoke character definitely does not last forever in the grain. I’ve heard of people buying rauchmalt and using as much as 30% in the recipe and barely getting any smoke. My thought is either the grain was old or they have a terribly worn out palate. Probably the grain.
Best place to buy rauchmalt is somewhere with a lot of turnover, just like buying hops.