I enjoy reading Michael Dawson's "The Beer Engine Blog" as well as Ron Pattinson's "Shut up about Barkley Perkins".
Michael was talking about the effect of head pressure and space during fermentation. He referenced research I performed on fermenter geometry in his writing. He suggested a few readers submit their results regarding fermentations. I agree to submit my findings.
I brewed a English Mild from Ron's blog - 1917 Whitbread X.
OG 1.045
Lots of different base malts, English hops, American Hops, invert sugar.
I brewed a 7 gallon batch and split it between two vessels.
1 6 gallon glass carboy with 3.5 gallons topped with an airlock, and 3.5 gallons in a 5.5 gallon stainless steel square topped with tin foil. I'll skim the excess yeast in the square during fermentation.
WLP007 - Wyeast 1098
Temperature - 63 degrees.
I was going to use Wyeast 1099 but that strain is a little too blah for me. This X has a lot of hops and I want those hops to come through, so I used the 1098 strain.
I also used a PH meter for the first time in this brew. I have used the good strips before, but after reading the Water book I decided I wanted to take advantage of the knowledge.
Check ph in mash with ph meter.
5.71 no salts - 3.5gallons water.
5.45 - 1g gysum, 1g calcium chloride
5.34 - 1g gysum, 1g calcium chloride
Sparged to 2Brix - 1.008. PH of mash was 5.81 when I stopped sparging.
End of boil ph was 5.64.
Might try acidify sparge water to try to control my ph better or maybe collect less wort.
This brew was also the first time I used my newly design false bottom. I used a combination of whole leaf hops and pellet hops. This false bottom worked well. I had a few seeds get by the bottom and into the pump but overall was pleased with the outcome. It's like my old kettles after the whirlpool and gives me more options on brew day.
These beers will be on my beer engine before you know it.
Update: I dirt skimmed the yeast after 24 hours in the square. There was a replacement krausen when I checked the square 4 hours later. I checked the square after 48 hours and the krausen is gone. There is a thin layer of yeast finishing up the fermentation.
The carboy still has a healthy krausen going.
Same beer, same volume, same yeast. The yeast was pitched by volume out of a measured flask.
The open ferment seems to be faster. I recovered the square with foil and will take a gravity reading of both when I transfer to cask.
Tasting notes.
I have both of these beers on a beer engine. I casked them each with
20g EKG, 80g corn sugar in boiled water, 1/2 packet gelatin in water 170F.
Open fermented beer finished at 1.009 and carboy finished at 1.010.
Open fermented beer is not as bright as carboy beer. The invert sugar comes across a little more in the open ferment and the hops come out brighter in the carboy beer. However I would say in a blind taste test in would be hard to tell the difference between the two.
Findings:
I would say wlp007 doesn't have much of a difference between open ferment and a carboy at fermentation temperature of 63 degrees.
