On my third brew, wondering how important fermentation temperature is

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dpaola2

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I've previously made two hazy IPAs via extract. This time I'm attempting a pale ale w/ all grain BIAB method. My goal is to up the quality of my brew, using liquid yeast.

I want to also control for the temperature of fermentation but it's proving far more difficult to find a mini fridge that will fit my carboy (I already have a temperature regulator and heating element).

I feel like I am upgrading the quality already by going all-grain instead of extract. Quality-wise, how much am I comparatively sacrificing if my fermentation temperature is, say, 5 degrees warmer than recommended?)

Thanks!
 
Fermenting at different temps will bring out different flavors with the same yeast. If you are off by 5 degrees, based on what I know the results would be different depending on what yeast you are using. 5 degrees off will still make beer by the way, it will just turn out differently!
 
Are you talking about the temperature of the active fermentation or the temperature of the are where you are fermenting? Keep in mind the temperature of the active fermentation is warmer than the area in which you are fermenting. From my experience it can be 8 - 12 degrees warmer in the fermenter than it is in the room where my fermenter is. Fermenting warm can create off flavors.
 
Fermentation temperature is very important because each yeast has an ideal temperature range at which to ferment, and as the poster above pointed out, fermentation creates heat of its own so your temperature inside the fermenter will be warmer than the ambient temperature.

You can still make beer without temperature control, but controlling it will greatly improve quality. Look for a chest freezer instead of a mini-fridge to use for controlling fermentation temps, pair it with a temperature controller, and attach the temp probe to the side of the fermenter and insulate it to read the fermenter as opposed to the air temp in the freezer. You can get a carboy carrier which will allow you to more easily lift the carboy in and out of the freezer.

I wouldn’t bother using a heat source to offset the cooling unless you are finding that the freezer is greatly overshooting on the cooling. Otherwise you’re just causing the two to fight against each other and run more often.
 
I believe controlling temperatures makes it more likely to run a high quality, predictable, fermentation that chews through the sugar at a steady pace to full attenuation and cleans up after itself as it goes. Having temps too high will accelerate yeast activity and yeast activity will further increase temps. Like a runaway reaction ... and I suspect the cause of many a new brewer's "painted" ceiling. At these higher temperatures many yeasts (but not all) will throw off undesirable flavors. Better to ferment in the lower half or midpoint of the yeast optimal range and then ramp it to upper end of optimal range towards end of fermentation.
 
Thanks for your advice! I do have a stopper w/ a built-in thermometer that connects to the temp regulator, so it should get an accurate reading of the actual fermentation rather than the air around the carboy.

It sounds like I might need to find a cool place and use heat to keep the temp up, rather than a warmer place and cross my fingers in hopes that it will stay cool.
 
I feel like I am upgrading the quality already by going all-grain instead of extract.

I would rephrase that a bit: You are increasing the need for quality procedures by going all-grain instead of extract. You are going from a tricycle to a bicycle. But it's still not a quality racing bike. It's just a proper bike with two wheels.

Now please (!) don't be offended by that analogy (you or other extract brewers). It's a viable way to make beer, and for some it's enough, and they enjoy it, and that's great. But it's not the "proper" way, meaning that it's not the full story; it doesn't allow a brewer to learn and exercise all of the craftsmanship opportunities available in brewing. It's not based on centuries of tradition. It's a short-cut.

So now you are taking up all grain, which is fantastic, but that's no guarantee of quality in and of itself. It's just "normal," a baseline if you will. Now the quality is, even more so, up to you, up to your knowledge and techniques. What's great is that sky's the limit in terms of where you can go with it.

If you peruse any of the threads "What was the one thing that improved your beer the most?" - you'll always see fermentation temperature control at the top of people's lists. It's not really optional, unless you limit yourself to styles and yeasts that work in your available ambient temps. And those do exist. But that's a limiting way to approach the hobby.
 
If you peruse any of the threads "What was the one thing that improved your beer the most?" - you'll always see fermentation temperature control at the top of people's lists. It's not really optional, unless you limit yourself to styles and yeasts that work in your available ambient temps. And those do exist. But that's a limiting way to approach the hobby.

I agree with this 100%. I noticed an improvement in quality and consistency when I started using a deep freeze with a temperature override as my fermenting chamber. There are other ways to control your temp like swamp coolers but I never had much luck with those.

As for yeast strains that work well in high temps check out Kveik strains. I have used Kveik Voss yeast in a hazy IPA and it fermented at 95 degrees F and turned out great.
 
Excellent answer, that's exactly what I was looking for! Thanks for giving it to me directly between the eyes.
 
And thank you for taking it in the right spirit! I was a little gun-shy that you or someone else might take offense. And I surely didn't mean it that way.

You're gonna have a great time. It's exciting to have that door opening up wide, which it really is. I get bored of things fairly easily, but brewing is such a cool blend of disciplines that there's always something to indulge the curious. You've got math, chemistry, biology, electronics, engineering, data management, and of course a wide range of sensory and gustatory stimulation. Plus <burp> a little bit of mental health therapy and social lubrication thrown in there for good measure.

One thing to consider - smaller batches. You don't have to brew 5 gallons of beer. It's a lot. And it means less experimentation because it's so much more to manage and store and refrigerate and keep around. And, if it's mediocre, so much to drink (or dump). I'll bet that a 3 gallon carboy, Fermonster, or Big Mouth Bubbler would fit in your mini-fridge.
 
What's the best way to scale down a recipe?

For example, I've got the cali mountain Sierra pale ale clone recipe kit from moreover waiting to be brewed, along with a pack of gigayeast liquid.
 
I'm late to the party. To answer your question of how important is fermentation temp , well its imo right up there with cleanliness and sanitization.

What do you mean scale down ? Are you saying its a 5 gallon kit but you only want 2.5 gallons?
 
Absolutely about the fermentation temp (includes primary and secondary). Realize the primary may add up to 10F to the ambient temp. This means the air around the primary, for example, is 60F, but inside the churning fermenter, the actual temp is 70F. 70F may exceed the recommended range of the yeast leading to unexpected aroma, smells or, even worse, pouring the whole batch down the drain.

Please don't replicate my brother-in-law whom swore he was brewing a lager in North Carolina temps just because he pitched a lager yeast and was fermenting in an uncooled garage. Yuck!
 
To address your question about scaling; software does make it easy. The all grain journey begins for some with kits, which gives you conveniently packaged ingredients in all the right proportions plus a generic suggestion about water volumes. But eventually you'll want to brew from recipes you see online or in books, where you buy the ingredients yourself. And of course, ultimately you'll devise your own recipes.

Many recipes give ingredients in absolute pounds (or kilos) with a particular batch size in mind. But that's a bit limiting, and you'll want to branch out from that. Using percentages is more practical; and of course, you can determine that from an existing recipe with just a little simple math. 5 lbs pilsner and a half pound of caramunich? Well, it's 5.5 lbs in total, and 5 / 5.5 = 91%. 0.5 / 5.5 = 9%. Now I can scale that up or down any way I like.

Grain and hops scale relatively proportionally, but water does not. This is because for a given kettle, heat strength, and boil time, the evaporation rate is the same - even if the desired ending volume is different. Meaning, the evaporation rate might be 1 gallon per hour. If you start with 6 gallons, you'll get 5. But if you want to get 2.5 gallons, you'll need to start with 3.5. It's not exactly proportional.

Again, software like Brewfather or Brewer's Friend makes scaling easy, and you can review the outcome of the scaling operation to understand how it works.
 
If you already have a temp controller and a heating element, just find an old fridge on craigslist for free or cheap. Take out the shelves. I have one I got free from a nieghbor years ago. Looks like crap but it's in the garage so who cares. it works.
 
Excellent responses, thanks again. I’ll be looking into software to assist with recipes. I think I’m going to try a 1 or 2 gallon batch today.
 
Controlling fermentation temperature is critical to producing quality brews. But..... that doesn't mean you necessarily need to go high tech or expensive. For now going on almost 9 years and over 170 batches I've relied on 1. brewing with the seasons, and 2. using a water bath to control my temps. Brewing by seasons: I do my lagers this time of year, and reserve ales for spring and altbiers/kolschs for fall. I have several muckbuckets that I put my fermentation buckets in. Monitor the temperature of the water bath a couple times daily, move it around to various areas in my basement and add frozen water bottles if it needs chilling or an aquarium heater if it needs warming. You do need to pay a little more attention that a 'set and forget' system, but it works well.
 
I agree with this 100%. I noticed an improvement in quality and consistency when I started using a deep freeze with a temperature override as my fermenting chamber. There are other ways to control your temp like swamp coolers but I never had much luck with those.

As for yeast strains that work well in high temps check out Kveik strains. I have used Kveik Voss yeast in a hazy IPA and it fermented at 95 degrees F and turned out great.

Would you mind posting a picture of your deep freeze with temperature overide? I have a friend who seems to be quite interested... :)
 
These controls are easy to wire.

Freezer Control-1.jpg
 
Ok cool, what exactly is a deep freeze though? Just a normal big freezer?

And so no one gets scared off by Tobor_8thMan’s nice setup, you don’t have to customize it at all to just use it as a fermentation chamber.

You just buy a chest freezer from somewhere like Best Buy and a temperature controller, and that’s all you need. See pictures below.

As you can see, the temperature controller would plug into the wall and the chest freezer would be piggybacked onto that plug. The temperature probe can just be run under the lid because it’s thin enough to still allow a good seal. Then you just set the temperature with the dial on the controller and it will cut the power on and off to meet your set temp.

You can also get more precise digital temperature controllers as well that include hot and cold sides so that you can heat your fermenter if necessary.

The setup below was my original temp control upgrade. The chest freezer ended up being taken over by breast milk and eventually extra food when COVID hit, so I finally went all in and bought a stainless steel fermenter with a temperature control coil and glycol chiller.
 

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Lots of people are saying to go for a chest freezer for a ferm chamber. I'm sure that would work. Though, I ended up getting a mini fridge that didn't have a freezer section. I'm sure if you got one with a freezer, you could just bend it downward (depending on how it's made, did this with my kegerator). And if extra room is needed, either cut away the shelfing stuff on the door, or make a wooden collar to extend the fridge door a bit (what I plan on doing soon).

Couple that with an inkbird temp controller and a thermowell and you've got yourself a working ferm chamber! I found my beer definitely fares better in there, with the one or two that have been made in there so far.
 
I use this with ice bottles inside. This is a Belgian Dark Strong Ale and it is my understanding it should ferment on the lower 60s the first few days or so then it can come up into the 70s. It is winter so my water is cold and my immersion chiller brought it down to 64 degrees.
37F31B13-761A-472E-BAD7-B7B6BA59CBBF.jpeg
 
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I think I’m going to try a 1 or 2 gallon batch today.
Many people find 2.5 gal batches (at packaging time) to be a good choice. This should yield around 24 bottles.

If you want to go smaller, pay close attention to fermenter sizes. Two gallon (food grade) buckets are good for brewing a 12 pack. One gallon carboys will yield a 6 pack + a couple of bottles.
 
A 3 gallon fermenter is a great choice for any batch size 2.5 gallons and under. The 3 gallon version of the Fermonster with a spigot is a perfect solution.

The more costly stainless Anvil 4 gallon unit and the SS Brewtech Brew Bucket Mini are also nice options.

Williams Brewing offers a simple plastic carboy as well, which is totally fine.
 
Most 1 gallon carboys don't have much headspace, so just keep that in mind. A blowoff tube is usually a must, depending on the OG, etc.
For a one gallon batch (of wort), I would use a 2 gallon pail - plenty of head space. Yields about 9 bottles (after packaging losses).

Basic Brewing's "Hop Sampler" is one good example of how to brew well with a one gallon carboy. Those batches target 3/4 gal of wort, 1 lb DME, roughly OG 55, and I find it yields a six pack. A nice result for sampling and plenty of head space in the 1 gal carboy.
 
And so no one gets scared off by Tobor_8thMan’s nice setup, you don’t have to customize it at all to just use it as a fermentation chamber.

You just buy a chest freezer from somewhere like Best Buy and a temperature controller, and that’s all you need. See pictures below.

As you can see, the temperature controller would plug into the wall and the chest freezer would be piggybacked onto that plug. The temperature probe can just be run under the lid because it’s thin enough to still allow a good seal. Then you just set the temperature with the dial on the controller and it will cut the power on and off to meet your set temp.

You can also get more precise digital temperature controllers as well that include hot and cold sides so that you can heat your fermenter if necessary.

The setup below was my original temp control upgrade. The chest freezer ended up being taken over by breast milk and eventually extra food when COVID hit, so I finally went all in and bought a stainless steel fermenter with a temperature control coil and glycol chiller.

So what you're saying is that they make temperature controls that I can just plug into the wall and then plug the chest freezer into without any wiring at all?
 
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