So, we’ve all heard that there is definitely a difference between mashing with a single infusion and mashing using a step Hochkurz. Better malt character/better attenuation/better efficiency with the 145F/158F of the Hochkurz, etc. I believe(d?) it. I did it. I probably even spouted the same thing as fact.
But is there really a difference?
Now that we have a Zymatic and can perform very precise measurements/procedures, I’m giving a real comparison a shot. I’ve brewed two identical German Pilsners using these two mashing techniques, taking readings at nearly every chance I could. I dumped the logged data out, overlaid the gravity readings, and now I’m sharing.
Recipe, for each brew day:
German Pils - based on Wort HOG’s recipe
Batch size: 2.5g
OG: 1.053
FG (anticipated): 1.012
IBU: 53
SRM: 5
5.5 lbs Best Pilsner
4 oz Carapils
4 oz Melanoidin
Bru’n Water: Yellow Dry
Ca 40, Mg 8, Na 8, SO4 91, Cl 29
60’ - Herkules - 15.8% - 0.35 oz
15’ - Vanguard - 4.8% - 0.75 oz
15’ - Saaz - 3.5% - 0.5 oz
WY2206, 2L starter in 5L flask. Shaken, not stirred. Pitched at high krausen.
Beer #1 (150F):
Mash times/temps: 104F dough-in for 10’, 150F sacc rest for 80’, 175F mash out for 10’
Target mash pH: 5.45
Actual mash pH: 5.47
Pre-boil SG: 1.051
Target boil pH: 5.0-5.1
Adjusted pH in ‘kettle’ to 5.01, 1.8mL 88% lactic
Post-boil SG: 1.053
Fast-ferment test (w/ bread yeast, expected to be 0.2 Brix high): 1.013
Beer #2 (145/158F):
Mash times/temps: 104F dough-in for 10’, 145F beta rest for 40’, 158F alpha rest for 20’, 175F mash out for 10’
Target mash pH: 5.45
Actual mash pH: 5.47
Pre-boil SG: 1.051
Target boil pH: 5.0-5.1
Adjusted pH in ‘kettle’ to 5.01, 1.8mL 88% lactic
Post-boil SG: 1.053
Fast-ferment test (w/ bread yeast, expected to be 0.2 Brix high): 1.013
Several interesting observations:
- There is a huge difference in speed of conversion between 145F and 150F. The 150F mash converted in about 30’ while the 145F mash never got to the same conversion in the 40’ and only reached that same conversion during the 158F rest. I thought it would be slower, but I didn’t think it would be that much slower.
- Each batch had EXACTLY the same gravity. The Z is basically a fully recirculating “brew in a bin” HERMS, I’m not sure if that has something to do with all of this, but it should be said.
- I’m also surprised at the work the mashout did on increasing the gravity. Here, it increased the SG by 17%. This is similar to what I’ve seen for other batches on the Z (+16-17%) for the mashout.
- The fast-ferment test indicated exactly the same FG for these batches, which also goes against what I’ve thought in the past. (More malt flavor, more fermentability.)
Some pictures:
Actual brew day, for the uninitiated:
The fast ferment test all set up:
Right after pitching the Hochkurz one (pitched the 150F about 12 hours ahead of time, since that was brewed in the morning and the other in the evening):
These have been rocking since 11/22/2015, and I’m about to take my first gravity readings and samples tonight. Pitched at 48F, fermented until 11/29 at 50F, now at 56F.
I do hope to do blind triangle tests on these and maybe trick some local judges into filling out scoresheets on them. We have some really great tasters in the area, so perhaps they could provide more insight/detail than “yes it’s different” or “they are the same”. (I wanted to do this on the Kolschs, but the beer did not turn out like I wanted, so it was not given out for that purpose.)
