Over the past week I made the first batch of malt for my Fifty Meter Beer Project brewday. There is still a second batch to prepare, but in this video I go over the process I used to convert the barley I grew this summer into a well modified and flavourful (I hope) base malt.
I didn’t include any of the math into the video, or put up key numbers on the screen, so I’ll put a couple of critical numbers and equations below. Chapter markers follow those equations. Note that for all of these equations you need the starting % moisture of your barley, which I show how to determine in Episode 14. The equations below have example calculations for a test bag that starts with 100 g of grain.
Note that for all of these equations you need the starting % moisture of your barley, which I show how to determine in Episode 14.
Starting Moisture Content for Various Base Malts:
- Pilsner: 38-42%
- Pale ale: 42-46%
- Munich: 46-48%
Kilning Temperatures (Pale Ale Malt):
- Initial Drying (reduce moisture to 20-25%): 35-38C, 12-16 hours
- Drying to <10%: 45-50C, 6-12 hours
- Curing: 80-95C, 3-5 hours
The equations below have example calculations for a test bag that starts with 100 g of grain.
Terms in the equations:
- SM = starting moisture (as a %)
- DM = desired moisture level (as a %)
- FW = final weight, once DM is reached
- SW = starting weight of the grain
- SDW = starting dry weight of the grain
- CM = current moisture content (%)
- CW = current weight
To calculate the expected weight of your barley, at the desired moisture content:
1) Calculate the dry weight (SDW) of your barley: SW * (1-(SM/100))
e.g. SDW = 100g @ 8% = 100 * (1-(8/100))
= 100 * (1-0.08) = 100 * 0.92
= 92 g
2) Calculate the final weight (weight once DM is reached): SDW/(1-(DM/100))
e.g. FW with a DM of 42% = 92g/(1-(42/100)
= 92/(1-0.42) = 92/0.58 = 158.6 g
To calculate the current moisture level (CM):
CM = ((CW-SDW)/CW)*100
e.g. CW of 120 g; CM = ((120-92)/120)*100
= 0.238100 = 23%