Headspace affecting krause?

[DonGavlar]

Hi guys,

Just a quick query. Im not really worried about it, more just intrigued, but at the moment im fermenting in a 7.5 gallon plastic fermonster and a 6.5 g big bubbler. Even though theres isnt a huge gallon difference, the fermonster has a considerably larger amount of head space than the big bubbler when brewing 5g batches.
Now, all my batches ive had in the big bubbler have had really nice thick healthy looking krausens, still no blow offs but some have come close. However, in the fermonster I get very little krausen, the thickest ive measured in it (including dried krausen ring incase i just missed the krausen) has only been about 1 inch thick maybe very slightly more. There has still been good airlock activity etc and I still see the yeast in action, especially with WLP002 but there just seems to be little to no krausen in that fermenter.
Is this just coincidence or does the large headspace affect the krausen? Im not worried as it still produces beer and im pretty sure big krausen size isnt a sign of good fermentation (may be wrong).
Anyone that could expand on this?

Thanks

 

[DonGavlar]

Sorry just to add, i currently have both filled and there were only 4 days between the two brews. The one in the fermonster had an OG of 059 and the big bubbler had an OG of 062, both using wlp001. Both are fermenting at the same temp, one a red ale the other a brown. The fermonster krausen has dropped and reached about an inch krausen, the big bubbler is still up and is at just over 6 inches of krausen.

 

[chris000]

whatever the reason is, the yeast did not look up and say: "oh, there's less room, so let's make sure we produce a little bit less Kräusen this time"

 

[myndflyte]

It's coincidence. There are too many other factors to say the fermentation vessel is having an effect on the krausen level.

 

[chris000]

It's coincidence. There are too many other factors to say the fermentation vessel is having an effect on the krausen level.

the only time when one could argue against that is if you compared something like a corny to a 4" shallow pan, where the ratio between volume and surface are vastly different.