A little bit of an experimental day in the Brew Shed. I wanted to try a two-stage infusion, starting the mash at 50C before raising the temperature to 70C after 30 minutes. This also meant I could try out my new STC1000 temperature controllers.
I had one controller attached to the hot water kettle, which was also on a timer. With the temperature probe in the water, the controller spends the night trying to heat the water but the timer prevents the heat from actually coming on. At the scheduled time – 7am – the timer switches the heater on and takes the water up to 60C, when the controller switches it off and then keeps it at 60C until I turn up to use it.
This setup also allows me to try out the big insulating jackets I made yesterday (from an old duvet covered in waterproof fabric) to minimise heat loss from the kettle. That worked well.
Turns out that 60C wasn’t hot enough to start the mash at 50C. The grains were so cold that added water at 60 only took the temperature to 46C. That would need to be enough.
The next problem was that I now had 30 litres of water at 60C, having taken off 30 litres to start the mash. Now I had to get that water to 100C to minimise the amount I would use to raise the mash temperature to 70C, which took longer than 30 minutes. But we get there and adding another 10 litres to the initial 15 litres took the temperature to 67C at which the mash sat for another 30 minutes while I got the sparge water up to temperature.
So that was a bit of a learning experience. Next time, heat the water more – 80C maybe so that the temperature of the mash water can be adjusted to be just right (and it won’t take to so long to boil it for raising the mash temperature.
Sparging and boiling proceeded as normal and I ended up with 55 litres of wort (90% pale and 10% crystal, hopped with Cascade, Amarillo and Chinook). Staying on the experimentation theme, I’ve split it in three and added different yeasts to each: Safale No 5, and American ale yeast, Mangrove Jack’s Belgian Ale and Mangrove Jack’s Bohemian Lager.
The temperature controllers are set to keep the two Mangrove Jack’s yeasts stable in the middle of their recommended range – the Belgian Ale between 26-32C and the Bohemian Lager between 10-15C. The Safale just has a heating plate and no controller.