slow fermentation

mrskittle

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Let me start by saying that temp control for fermentation is on top of the to-do list because I fully expect it to rectify my issues. But in the meantime, I have an IPA that is just chugging along slow and steady. It's 4 gallons of a pretty standard IPA that has been in the carboy for 16 days and I'm still seeing active fermentation. There is still some foam/krausen on top, the air lock is bubbling every 7 seconds or so, and I'm still at least 10 points from my typical finishing gravity, but it does continue to go down, slowly. I don't have any glaring indication of a stuck fermentation or any other big issues but this experience is different from what I've had so far so I'm just looking for some insight. I have identified a couple of variables that could be behind the change in fermentation behavior.

First: The yeast is White Labs Cali ale yeast and It's on the 4th generation. I usually make a starter a couple of days ahead of time and split the yeast. I use one to pitch and put one in the fridge for next time. How many times can I propagate this way before the yeast starts losing vitality?

Second: The average termp in my basement is about 63 degrees for 16-18 hours/day but the thermostat is set for 62 overnight and I'm not entirely sure how many degrees the basement drops overnight. Being a basement, the temp doesn't generally swing very far, very fast but I suspect the temp could drop down to 60 or slightly below. Could a mild and regular temp change like this contribute to a slow fermentation?
 
I'd say your basement temps are a bit low for that yeast. White Labs has the suggested fermentation range listed at 68-73.
 
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I'd say your basement temps are a bit low for that yeast. White Labs has the suggested fermentation range listed at 68-73.

There's no question that it's cooler than the yeast would prefer. Other than extending the time of fermentation, will fermenting below the recommended temp have negative effects on the finished product? As long as the process is proceeding as expected, I feel like the finished beer shouldn't suffer.

I did bring the carboy up into my dining room where it's warmer. Hopefully it'll finish off in a few more days. I was hoping to dryhop but I think I'll wait and do it in the keg. It's time to get this beer out of the carboy.

For curiosity's sake, what kind of effect does the typical temp swing in a home have on yeast? That is assuming most folks lower their thermostat overnight.
 
It’s a Chico strain, it can go lower than White Labs recommends. The low temperature will not hurt your beer at all. In fact I prefer pale ales and iPA’s fermented at lower temperatures. Whenever you ferment at lower temperatures, your pitch rate increases. So if you pitched a little light, the fermentation takes longer. Let it finish and taste it. I think you worried about nothing.

In the future, if your basement is that cool, use SO4. It tolerates low pitches and low temperatures. It produces very good American beers, even though it’s an English strain. SO4 also tolerates higher temperatures too.
 
Is your yeast 001 or 051? Both called "Cali". Assuming it's 001, you're definitely running cool. The .051 would benefit from warmer temp, as well, but it has some characteristics of lager yeasts and might stand the cooler environment better. Either way, warm it up to 68 to drive off diacetyl and it should finish out just fine.
 
For what it's worth, I use a heating pad - the kind for a sore back - when things get too cool. Bungee cord holds it to the side of the fermenter, and it has low-medium-high settings.
 
For what it's worth, I use a heating pad - the kind for a sore back - when things get too cool. Bungee cord holds it to the side of the fermenter, and it has low-medium-high settings.
My fermentation chamber is an upright freezer with a two-stage temperature controller. The cold side powers the freezer, the hot side a Fermwrap taped to the back of the freezer. I have to keep the temperature probe in the "open air", otherwise the temperature yo-yos way too much.
 
For what it's worth, I use a heating pad - the kind for a sore back - when things get too cool. Bungee cord holds it to the side of the fermenter, and it has low-medium-high settings.
An inexpensive controller like the Inkbird can be used to keep a very constant temp in conjunction with a heating pad. As long as the heating capacity is there to overcome ambient temperature it'll keep the fermenting beer nice and toasty and stay within a degree or two of the target. It's a great method for holding temp in cool climates.
 
I picked up a sheet of 1in pink foam today and will be constructing a chamber soon. That stupid stuff is $20 for 4x8 1inch sheet, but I digress. I still have to pick up a temp control but in the meantime I'm going to try a timer and an incandescent light bulb. The timer can be set by 30 min increments so we'll see if I can find a sweet spot. I've got to replenish the budget before I can buy the temp controller. Same for a used minifridge, but for the next 6 months keeping things warm is the issue. The fridge can wait.

I'm also trying to figure out how to have 1 chamber and two different climates. I always have fermentations in different stages so they usually won't have the same temp needs. Has anyone does this? Is there a temp control that can control 2 different heat sources?
 
I picked up a sheet of 1in pink foam today and will be constructing a chamber soon. That stupid stuff is $20 for 4x8 1inch sheet, but I digress.
That's down from last year. I insulated my barn last year and paid @ $25 a sheet.

As far as your chamber, I have built several and have a several keezers. I found that using a yeast that best suits the ambient temperatures works as well as a chamber. Ale yeasts can handle fluctuations in temperature as long as they are not to severe. Keep in mind that the beer will not swing wildly with room temperatures because of it's thermal mass.

Unless I'm brewing a lager, I try to ferment beers at room temps. Nearly all my ales (my house beers) are fermented at room temp whenever possible. I chose a yeast that fits the time of year, SO4 for winter and Voss for summer. That's why I recommended in a previous post to use SO4, it has a big temperature range and is very forgiving of low oxygen levels, pitch rates and temperature. It's cheaper than a chamber and less hassle. If you get into Belgians or lagers, now the temperature gets a little more critical.
 
My fermentation chamber is an upright freezer with a two-stage temperature controller. The cold side powers the freezer, the hot side a Fermwrap taped to the back of the freezer. I have to keep the temperature probe in the "open air", otherwise the temperature yo-yos way too much.

Other than the orientation of the freezer, this is the same method I employ.
 
For curiosity's sake, what kind of effect does the typical temp swing in a home have on yeast? That is assuming most folks lower their thermostat overnight.

When I don't have access to my fermentation chamber (chest freezer) I actually place the house thermostat on hold so the temp does not drop at night. Shhhh....don't tell the wife :D
 
I picked up a sheet of 1in pink foam today and will be constructing a chamber soon. That stupid stuff is $20 for 4x8 1inch sheet, but I digress. I still have to pick up a temp control but in the meantime I'm going to try a timer and an incandescent light bulb. The timer can be set by 30 min increments so we'll see if I can find a sweet spot. I've got to replenish the budget before I can buy the temp controller. Same for a used minifridge, but for the next 6 months keeping things warm is the issue. The fridge can wait.

I'm also trying to figure out how to have 1 chamber and two different climates. I always have fermentations in different stages so they usually won't have the same temp needs. Has anyone does this? Is there a temp control that can control 2 different heat sources?
Even a used chest freezer will do the job perfectly for keeping your fermentations warm.
My first two ferm fridges were freebies.
My current chest freezer was 50$ it's about 5 years old now and my keezer freezer was $60
You can get em for free if you look around hard enough.
A brew mate of mines been using an esky or in your terms a large cooler to keep his fermentations warm using a heat belt on a timer. For cheap as chips you can get an Stc1000 if your cool with a bit of DIY wiring.
 
I'm going to try a timer and an incandescent light bulb. The timer can be set by 30 min increments so we'll see if I can find a sweet spot.
Also consider experimenting with bulb wattage. My heating pad is 50 watts on 'high' and it will raise 5 gallons 10 to 15 F above ambient with no insulation. An incandescent bulb emits almost all its consumed energy as heat.
 
The beer in question finished up beautifully, albeit in my dining room. In the meantime I was able to throw together a fermentation chamber. Its pretty crude but should do just fine for now. It'll need some work when I get around to adding a fridge for cooling. A different beer with the same yeast finished up much more predictably once it was warmed up in the chamber just a few degrees. In fact the latent heat from a 5-gallon batch in vigorous fermentation was enough to moderate temps. I threw together a little apparatus to hold a light bulb surrounded by ceramic tiles (leftover from bathroom floor) to provide a nice, mellow heat. With $2000 in car repairs on the horizon, I'll be sticking with the cheapo version for the time being... A temp controller has been bumped down the list of purchases.
 
I scored a free minifridge last year that I use as a fermentation chamber. So that is a good option in my opinion.
 

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