Following the procedure in this excellent blog post, we did six micro mash test batches for a porter or double mild we’ve been thinking about brewing. We’ve been talking about brewing a porter for months now, but haven’t been able to agree on a recipe. Wind likes dry and roasty, Esme likes sweet and smooth. But there are also some outliers like Esme liking dark mild, but Wind doesn’t. When we have a porter or stout, it almost always turns out that one of us really likes it, the other doesn’t like it nearly as much.
We’ve experimented with multiple batches for trying different yeasts before, but didn’t have a process for trying different grain bills. So it was nice to find this process, which scales down a batch to quart size and then mashes and boils in mason jars. We made a few changes, with mixed results:
- Instead of using malt extract, we did an all-grain mash because we wanted to test the difference between mild and pale ale base malts. We scaled our recipes down to 11.5 oz. of grain, which almost filled the mason jar, and were able to fit about 18 oz. of water. This worked reasonably well, but the mash efficiency was only about 45-50%, compared to the 70-80% we usually see with our usual mash process (Igloo cooler and fly sparging). So we would recommend doing a separate, larger scale mash to test different base grains (or accepting 50% efficiency and boiling down for higher gravity).
- Because we were using more grain, a small strainer wouldn’t be big enough. So we used a pasta strainer lined with mesh bags (usually used as hop sacks). This worked very well, and gave us room to sparge the grains. We used the same setup post-boil to filter out the hop detritus.
- We tried to do the boil in our usual kettle, using a canning rack to hold the mason jars. This seemed better than microwaving, since we’d be able to see them while boiling, easily add hops at the right times, etc. But the mason jars didn’t boil – an hour after the water bath started boiling, they were still slowly converging on 200°F. So we pulled them out and microwaved them, which worked fine.
This is a good process for trying out different grain bills, especially different specialty grains over a base malt you can get in powdered or syrup form. We’re looking forward to figuring out a grain bill we both like and brewing a full batch soon.