I’m brewing an extract Barley Wine kit (from More Beer!), with Safale US-05 yeast. I know a lot of you much more experienced brewers follow a schedule of holding the temperature somewhat low for a few days and then increase it for a few days more before cold crashing. I set my fermenter at 65F at the outset–which is the ideal mid-point temp for this yeast–and have held it there for the past nine days with steady, though decreasing, airlock activity throughout this time. My Tilt hydrometer indicates that the SG continues to drop: from an initial reading of 1.087 to 1.024 this morning. If I’m still seeing airlock activity and the SG continues to drop, is there a reason to increase the temperature, or should I just let it ride at 65 degrees until the Tilt suggests fermentation has stopped? I don’t have a glycol chiller, so cold crashing is not an option for me.
Your call on that - you won’t hurt the beer by allowing it to rise a few degrees at this point. If you pitched enough yeast and it is still descending in gravity, you don’t need to do anything. But some increase the temperature a bit to help the yeast keep going to finish out; some will also gently swirl the fermenter to rouse the yeast a bit toward the end of fermentation. It sounds like you have this well in hand, if that is any help. Cheers and enjoy your barleywine when it’s done.
P.S. That Tilt is great, isn’t it? Even when it isn’t completely accurate (krausen sticks to it sometimes), it still helps determine when the fermentation is finished.
I set my fermenter temp controller to one temp and leave it. But I use a yeast that works with that profile. I think you’re safe with US-05 leaving it as well.
If you’re using a strain that needs to have a temp increase or decrease then that should be considered.
I’ve heard Jamil talk about certain English strains that ferment at 70*F that the temp needs to be reduced for a diacetyl rest to influence the yeast to drop thru the beer and clean it up. I thought that was interesting.
Other strains need to have the the temp raised for the diacetyl rest.
I would raise the temperature a few degrees because IMO, it might help, and it won’t hurt. I like to keep things simple when possible.
Many thanks for the great advice, friends! Glad to know that much more experienced brewers than I hold the temp with yeasts like US-05 and raise it a bit near the end of the fermentation cycle. Putting this wise counsel to good use I’m going to watch the Tilt readings and when the fermentation seems to be slowing down I’ll raise the temperature a couple of degrees to finish out.
And, yes ynotbrusum, I agree that the Tilt is a great tool! I rock the fermenter back and forth now and then to try to loosen the krausen (and maybe that wakes up the yeast a little too), but it really helps to determine when fermentation has probably ended.
In the book Yeast, White and Zainashef advise to keep temperature steady until the last 1/3 - 1/4 of fermentation - then raise the temperature 4 - 10 degrees F over 1 - 2 days. I’d guess you’re probably in the last 1/4 of fermentation now.
That is good advice for strains that throw high levels of esters and/or diacetyl. However, US-05 and BRY-97 are almost squeaky clean for being ale cultures. I do not see any advantage to a rising temperature program with these cultures. A steady temperature between 64 and 68F will yield good results with that said, I am starting to refer to as the descendants of the Narragansett culture (a.k.a. BRY-96). Even though Narragansett brewed Ballantine XXX after Falstaff shutdown Ballantine, UW ruled out Ballantine as the source of the culture; therefore, we are left to assume that it has roots in Rhode Island. Only Siebel knows for certain and I am willing to bet that the person or persons who received the culture in 1967 are no longer with us. All roads now point to the culture Narragansett used for their Banquet Ale before the acquisition of the James Hanley Brewing Company or it is James Hanley’s culture. Genetic sequencing will eventually tell us from where it originated. Single-nucleotide polymorphisms (SNPs) will lead us to BRY-96’s parent. Hopefully, UW will donate the sequences from their study to the NCBI genetic sequence database.
I’m lost on the connection between being a clean yeast and not needing a rising temperature. Could you elaborate?
Holding fermentation temps lower decreases esters. Raising fermentation temps towarda the end reduces diacetyl. If the yeast isn’t producing much in the way of esters or diacetyl, then there isn’t much to gain by starting low and then ramping up fermentation temps.
A fermentation profile that includes rising temperatures is due to the yeast creating a lot of metabolic trash in the early stages of fermentation. Increasing the temperature results in greater fermentation activity near the end of fermentation. We can think of esters and diacetyl as the the fermentation equivalent of incomplete combustion. Raising the temperature increases yeast metabolic rate which, in turn, causes the yeast cells to clean up after themselves, as they scavenge for sources of carbon to convert to ATP.
In the Yeast book, benefits of raising the temperature include being more likely to attenuate fully. That seems to be a different issue, and I think there is some skepticism about it. Maybe erockrph and Saccharomyces are skeptics, and I’m not completely sure. But since there doesn’t seem to be a downside, I go ahead and raise the temperature. ymmv.
That’s what I do, using the same theory. After about 4-5 days I raise the temp. It’s easy in my setup, may help, doesn’t seem to hurt.
Thanks once again, everyone. I really appreciate these helpful insights!