Porter Fermentation

[BeginnerBebeBrewer]

Hi Everyone,

I had a quick question, I'm currently brewing my first dark beer - a porter all grain kit. Usually my go to beer is a hoppy pale/IPA and using US-05 it ferments out within a week using my controlled temperature setup.

I had a packet of US-05 left over for this beer so I have used that in this recipe. My question is that I've noticed that whilst the beer is bubbling away nicely the rate of fermentation is much slower (I've dropped down from 1.060 to 1.050 in about 4 days). I have no problem leaving the beer bubbling away but I was wondering whether this was a common thing to have a slower fermentation for darker beers? Are the sugars that the yeast utilize more complex and therefore take longer or does the darker beer cause a change in the pH compared to pale ales and therefore less yeast are around to do the fermentation?

Thanks for everyones help.

 

[jerbrew]

Hi Everyone,

I had a quick question, I'm currently brewing my first dark beer - a porter all grain kit. Usually my go to beer is a hoppy pale/IPA and using US-05 it ferments out within a week using my controlled temperature setup.

I had a packet of US-05 left over for this beer so I have used that in this recipe. My question is that I've noticed that whilst the beer is bubbling away nicely the rate of fermentation is much slower (I've dropped down from 1.060 to 1.050 in about 4 days). I have no problem leaving the beer bubbling away but I was wondering whether this was a common thing to have a slower fermentation for darker beers? Are the sugars that the yeast utilize more complex and therefore take longer or does the darker beer cause a change in the pH compared to pale ales and therefore less yeast are around to do the fermentation?

Thanks for everyones help.

It would definitely be considered "normal" behavior to see variations in fermentation if the the only thing you're keeping the same is dumping a package of us-05 into cooled wort. That said, nothing wrong with dumping in a package of us-05. You'll just find that as you look around the threads and responses that brewers go through a potential gauntlet of factors and conditions to maintain consistency even with the same recipes fermentation behavior. There are too many factors involved to explain simply why one fermentaiton may take longer than other.

 

[Pappers_]

Its not the complexity of the sugars due to dark malt, I'm pretty sure. What were your mash temps? That would definitely impact fermentability of the wort.

Don't know about how the pH would impact the fermentation, usually I think that's a mash issue. Interesting to see if anyone else knows about that.

Could be the age of the yeast, the OG, pitching temp, or just the randomness of yeast. Slower fermentation does not equal worse beer, in fact it can often be the opposite at the homebrew level.

 

[flars]

I would just hold the highest temperature reached during active fermentation without knowing anything about your ingredients or mash temperature. After four days in the fermentor you could bump up the temperature of the beer a few degrees until it finishes. Take another SG reading in a week from now.

 

[Calder]

I had a packet of US-05 left over for this beer so I have used that in this recipe. My question is that I've noticed that whilst the beer is bubbling away nicely the rate of fermentation is much slower (I've dropped down from 1.060 to 1.050 in about 4 days). I have no problem leaving the beer bubbling away but I was wondering whether this was a common thing to have a slower fermentation for darker beers? Are the sugars that the yeast utilize more complex and therefore take longer or does the darker beer cause a change in the pH compared to pale ales and therefore less yeast are around to do the fermentation?.

Beer bubbling away and only dropped 10 points in 4 days. Something is up. I assume temp was OK - anything above 60 F is OK for that yeast. 4 days should be plenty enough time for yeast to get to full strength, so providing it is bubbling, you should have plenty of healthy yeast.

Complexity of sugars are dependent on mash temp. Yes, extra crystal will add some additional complex sugars, but for the rest of the grains, most of the sugars are produced during the mash, so type of beer should not have any significant impact on fermentation time.

My guess (wild ass guess not knowing much), is that you either mashed too high and have a highly unfermentable wort, or you are using a refractometer and not correcting for the result. See if the gravity comes down more in the next few days and prove me wrong (I hope you do). Desperate measures could be to use a more aggressive yeast (3711, etc) or even resort to using beano (I've never used it).