Temp control equipment question

[GolFisHunt]

My basement, where I store my fermenting beer, is consistently at 62-65 degrees F. Seems a little on the low side. I'm considering the temp control kit from NB. Is this a good investment in better beer? Is there better/cheaper equipment out there? Am I wrong in thinking it is too cool in my basement?

 

[Smellyglove]

I'd say 62-65f is a fine ambient temperature. Especially the low end when you pitch a batch. The thing you should be focusing on is not letting it rise to much, then drop to much. My tip is to always start low for "regular" ales, makes for a stable fermentation if the lag-phase is done cold. I never use a Diacetyl-rest as it's not needed then.

I usually pitch my ales at 14-16C, then pull them up to 19C over the course of 18 hrs. I cap the english ales a little bit higher though, for some more fruitiness. But the "clean" ones are capped ad 19C, after a low pitch.

 

[GolFisHunt]

I appreciate the response. Temperature fluctuation hasn't been a problem. I'll go look up "Diacetyl-rest" now.

 

[Timberline]

Consider too that fermentation is an exothermic process; so the actual wort temp is typically slightly warmer than ambient.

 

[AJinJacksonville]

Even in winter when my garage gets down to ale fermenting temps (I'm in FL), I use the temp controller in my chest freezer fermentation chamber for consistency. You can either buy them online or build them yourself. I'm a DIY type of dude, so I looked it up on YouTube and in the forums here to craft my temp controller. A dual stage will keep it warm when it needs warmth, and cool when it needs cold. Timberline is right though...always remember that the yeast is producing warmth during the fermentation process. Although the ambient may be XX, the liquid will be XX + X.

 

[Nagorg]

A consistent 62-65 degrees sounds awesome for most ales. Sure wish I had that! Even so, you cant go wrong with better temp control. Plus the flexibility for lower or higher temps is a big plus!

 

[GolFisHunt]

Thanks for the info, Gents!

 

[ScrewyBrewer]

My basement, where I store my fermenting beer, is consistently at 62-65 degrees F. Seems a little on the low side. I'm considering the temp control kit from NB. Is this a good investment in better beer? Is there better/cheaper equipment out there? Am I wrong in thinking it is too cool in my basement?

Flavor precursors, aka off flavors, are produced during primary fermentation. The amount of flavor precursors are determined by the temperature of the fermentation. Once all of the sugars have been converted to alcohol and Co2, the yeast absorb the flavor precursors rendering them tasteless.

There is one thing to look out for though. This is where temperature control makes a big difference. Yeast can only absorb flavor precursors produced at their highest fermentation temperature. Up to a point. There are some limitations. I'll explain.

Flavor precursors produced during active fermentation at 75F, will be absorbed by the yeast and rendered tasteless, only when the fermenting beer is at same 75F temperature. As posted earlier. During active fermentation the temperature of the fermenting beer can rise 3F-5F above ambient room temperature. If the fermentation temperature were allowed to reach 75F during active fermentation, and then fall to 70F for the remainder of the fermentation, a percentage of flavor precursors will remain in the beer.

A temperature controller, with a probe and thermowell in contact with the fermenting beer, can provide the most accurate fermentation temperature measurements. While it is nice to know what the ambient temperature of the room is, its not the best way of knowing what the core temperature of the fermenting beer is.

https://www.homebrewtalk.com/yeast-femrnetation-phases.html

 

[JONNYROTTEN]

Flavor precursors, aka off flavors, are produced during primary fermentation. The amount of flavor precursors are determined by the temperature of the fermentation. Once all of the sugars have been converted to alcohol and Co2, the yeast absorb the flavor precursors rendering them tasteless.

There is one thing to look out for though. This is where temperature control makes a big difference. Yeast can only absorb flavor precursors produced at their highest fermentation temperature. Up to a point. There are some limitations. I'll explain.

Flavor precursors produced during active fermentation at 75F, will be absorbed by the yeast and rendered tasteless, only when the fermenting beer is at same 75F temperature. As posted earlier. During active fermentation the temperature of the fermenting beer can rise 3F-5F above ambient room temperature. If the fermentation temperature were allowed to reach 75F during active fermentation, and then fall to 70F for the remainder of the fermentation, a percentage of flavor precursors will remain in the beer.

A temperature controller, with a probe and thermowell in contact with the fermenting beer, can provide the most accurate fermentation temperature measurements. While it is nice to know what the ambient temperature of the room is, its not the best way of knowing what the core temperature of the fermenting beer is.

https://www.homebrewtalk.com/yeast-femrnetation-phases.html

Am I reading this correctly? If you ferment warmer than ideal (75) and keep it there the entire time the yeast absorb any off flavors and your good. If the temp is at 75 for a portion of the fermentation and dropped to correct it will ADD off flavors? I was always under the impression if the temp rises during fermentation that's when the off flavors come in and try to lower the temp ( catch the problem) in time to save the beer.

 

[mongoose33]

I don't know which temp control kit you're thinking about, but I looked and I thought they were terribly expensive for what they are.

Get a Fermwrap ($25 on Amazon), get an Inkbird (https://www.homebrewtalk.com/showthread.php?t=636817) using Inkbird's special, about $30 on Amazon.

That's all you need to maintain heat. Look for a small refrigerator so you can also control high temps, not just low temps, and there you are. I use 4.4 cu foot dorm-style refrigerator as well as a larger one to control ferm temps.

I also have a reptile cage heat mat I use for warmign a fermenter. Not as quick as the fermwrap (which I also have) but still works fine.

 

[GPP33]

I'll second what everyone else is saying, that sounds like a great temp. The fact that (a) you see some fluctuation in your temp and (b) the beer warmer than ambient tells me you do need a more active control method though. There's lots of ways to do that but a cheap easy and compact method is just a big ass tub of water with an aquarium heater. The large water mass will absorb the temp fluctuation and will act as a heat sink for the fermenting beer. The tub will stay just a little cooler than ambient due to evaporation, the heater will allow you to tune in the temp you want. You also want to measure the temp of the beer, running the aquarium heater off a temp controller (ink birds are cheap and easy) that reacts to the beer temp is your best bet.

 

[eric19312]

There is one thing to look out for though. This is where temperature control makes a big difference. Yeast can only absorb flavor precursors produced at their highest fermentation temperature. Up to a point. There are some limitations. I'll explain.

Flavor precursors produced during active fermentation at 75F, will be absorbed by the yeast and rendered tasteless, only when the fermenting beer is at same 75F temperature. As posted earlier. During active fermentation the temperature of the fermenting beer can rise 3F-5F above ambient room temperature. If the fermentation temperature were allowed to reach 75F during active fermentation, and then fall to 70F for the remainder of the fermentation, a percentage of flavor precursors will remain in the beer.

https://www.homebrewtalk.com/yeast-femrnetation-phases.html

Hey Screwy I appreciate you referenced your own HBT article on this matter but I'd really be interested to see underlying source to this statement. I like the logic and assume it works well within certain parameters and nicely fits reason to bump temp a bit at end of ale fermentation like I do...can you provide a better source, something that traces back to something authoritative...preferably that had ability to detect these off flavors or flavor precursors using scientific instruments rather than tasting panels?

 

[eric19312]

I used STC1000 with an old fridge and a light bulb in a can for warmth successfully for years. Lately though after increasing batch size and perhaps the insulating properties of my fermentor I've noticed some off flavors in my beers and got a datalogger to track actual fermentation temperatures. Sure enough I was getting some pretty big swings especially in first 48 hours of fermentation with my active control overshooting target temperature both high and low. I looked into BrewPi Spark and some other PID control based systems but in the end found this recently released device from Auber called the DT500 and am pretty happy with it so far.

Here is a thread I started on it... https://www.homebrewtalk.com/showthread.php?t=634873
for the DIYers out there #FunkedOut suggested a cool way to make one using 3 STC1000s which would probably come in at about $50-$60 although I think the silicon gap sensors on the Auber product might be better quality and more stable over long term than the NTC probes on the STC/Inkbird controllers and the Auber works in F or C.

 

[Smellyglove]

Flavor precursors, aka off flavors, are produced during primary fermentation. The amount of flavor precursors are determined by the temperature of the fermentation. Once all of the sugars have been converted to alcohol and Co2, the yeast absorb the flavor precursors rendering them tasteless.

There is one thing to look out for though. This is where temperature control makes a big difference. Yeast can only absorb flavor precursors produced at their highest fermentation temperature. Up to a point. There are some limitations. I'll explain.

Flavor precursors produced during active fermentation at 75F, will be absorbed by the yeast and rendered tasteless, only when the fermenting beer is at same 75F temperature. As posted earlier. During active fermentation the temperature of the fermenting beer can rise 3F-5F above ambient room temperature. If the fermentation temperature were allowed to reach 75F during active fermentation, and then fall to 70F for the remainder of the fermentation, a percentage of flavor precursors will remain in the beer. I start it low though, as with every pitch I do. But the point is that if you keep the yeast active, it will consume off-stuff, in the end.


https://www.homebrewtalk.com/yeast-femrnetation-phases.html

Yes, but also no. The common thing is to "to let the yeast clean up with a D-rest at the same temp or higher as the pitch-temp. D-rest is a term, Diacetyl-rest, which people say when they mean that you should heat the beer up at the end of primary fermentation to clean out remaining Diacetyl, but there are other off-flavors than D it can clean up in the same sweep.

But. If you keep the yeast still active, it will consume off-flavors. The time it takes is dependent on the temperature (which implies the activity of the yeast).

You can perfectly fine clean out all (for instance) Diacetyl which is above flavor threshold even if the latter part of the fermentation is done at a lower temperature than the initial part of the fermentation. Here comes the vitality and viability-part of a pitch. If you've pitched enough healthy yeast, it will most likely reabsorb off flavors, even at a lower temperature, but it might take a while longer, comparing to an elevated temperature at the end.

But, to make sure everything is cleaned out, it is advised to raise the temperature to the highest temperature which was recorded during the most active fermentation.

I have one beer where I drop the temp 4C during the active fermentation, ends up clean as a whistle (when it comes to off-flavors, but it's loaded with the phenols i'm after, which are correct for the strain). Packaging after about 6-8 days, with loads of active yeast, so the carbonation in the bottles is done in about three days, and no off flavors. Bottles never see same temps same as primary fermentation.

Either way, fast or slow. I would advise to always pitch cooler than ferm-temp, and controlling the temp.

 

[ScrewyBrewer]

Hey Screwy I appreciate you referenced your own HBT article on this matter but I'd really be interested to see underlying source to this statement. I like the logic and assume it works well within certain parameters and nicely fits reason to bump temp a bit at end of ale fermentation like I do...can you provide a better source, something that traces back to something authoritative...preferably that had ability to detect these off flavors or flavor precursors using scientific instruments rather than tasting panels?

Sure thing. The authoritative source for this and other related articles is the book "Yeast: The Practical Guide to Beer Fermentation" by Chris White and Jamil Zainasheff.

 

[Dcpcooks]

Great book! ^^^^^^^ changed the way I look at those little critters.

 

[ScrewyBrewer]

Am I reading this correctly? If you ferment warmer than ideal (75) and keep it there the entire time the yeast absorb any off flavors and your good. If the temp is at 75 for a portion of the fermentation and dropped to correct it will ADD off flavors? I was always under the impression if the temp rises during fermentation that's when the off flavors come in and try to lower the temp ( catch the problem) in time to save the beer.

I'm not sure that you are. Let me start by recommending to always ferment within the manufacturer's optimal temperature range for each yeast type. You also want to pitch enough viable cells, as pitching too few viable cells will stress the yeast and promote the production of esters, and several other issues. The use of 75F in my earlier post was just to make a point, 85F could just as well been used. Fermenting at higher than recommended temperatures stress the yeast which in turn encourages the production of esters.

For example let's say the yeast pitched has an optimal temperature range of 65F - 75F. Relying only on an ambient room temperature of 65F for temperature control, the yeast is pitched into 70F wort. Logically the wort begins to cool off a bit until the primary fermentation begins. The heat generated by the active fermentation raises the temperature up to say 74F for this example. Making 74F the peak fermentation temperature where ester production occurred.

At the end of primary fermentation the 65F ambient room temperature eventually cools the fermenting beer down to say 65F. For the yeast to absorb esters produced at the peak fermentation temperature of 74F, the temperature of the fermenting beer should gradually be raised to 74F. This is where the advantages of fermenting beer in a temperature controlled environment come in. Keeping fermentation temperature within plus or minus 0.5F during primary fermentation helps to eliminate the production of esters in the first place.

Gradually raising the fermentation temperature to the peak fermentation temperature should be done before the yeast go dormant. The yeast cells still need to be active to have time to absorb the remaining esters. A good indicator for when to start raising the temperature is seeing just one or two bubbles per hour in the airlock.

 

[Nagorg]

Is the BrewPI still viable? I just bought parts and will be attempting the build soon. The info just seemed a bit dated... The Fermostat looked awesome but reviews show it to be plagued with instability and sub-par support so the BrewPI looked like a win. (Been using an STC-1000 successfully but want to deal with related overshoots...)

 

[ScrewyBrewer]

Is the BrewPI still viable? I just bought parts and will be attempting the build soon. The info just seemed a bit dated... The Fermostat looked awesome but reviews show it to be plagued with instability and sub-par support so the BrewPI looked like a win. (Been using an STC-1000 successfully but want to deal with related overshoots...)

Have you looked into using an STC-1000+. I'm not familiar with the STC-1000 but the STC-1000+ has a hysteresis and other features built into its firmware.

http://www.boostbysmith.com/stc1000.html

 

[Nagorg]

Have you looked into using an STC-1000+. I'm not familiar with the STC-1000 but the STC-1000+ has a hysteresis and other features built into its firmware.

The STC-1000 provides more basic features but it is dual stage with configurable hysteresis as well. So, in that sense I am dealing with the temp swing via a heater that comes on when the temp crosses the low point.

What I'm looking for with the BrewPI is more intelligent cooling/heating cycles that are adjusted by thermal response of the fermenting beer. Not to mention that having a web portal for monitoring it all would be a huge plus too!

 

[mongoose33]

Yes, but also no. The common thing is to "to let the yeast clean up with a D-rest at the same temp or higher as the pitch-temp. D-rest is a term, Diacetyl-rest, which people say when they mean that you should heat the beer up at the end of primary fermentation to clean out remaining Diacetyl, but there are other off-flavors than D it can clean up in the same sweep.

But. If you keep the yeast still active, it will consume off-flavors. The time it takes is dependent on the temperature (which implies the activity of the yeast).

You can perfectly fine clean out all (for instance) Diacetyl which is above flavor threshold even if the latter part of the fermentation is done at a lower temperature than the initial part of the fermentation. Here comes the vitality and viability-part of a pitch. If you've pitched enough healthy yeast, it will most likely reabsorb off flavors, even at a lower temperature, but it might take a while longer, comparing to an elevated temperature at the end.

But, to make sure everything is cleaned out, it is advised to raise the temperature to the highest temperature which was recorded during the most active fermentation.

I have one beer where I drop the temp 4C during the active fermentation, ends up clean as a whistle (when it comes to off-flavors, but it's loaded with the phenols i'm after, which are correct for the strain). Packaging after about 6-8 days, with loads of active yeast, so the carbonation in the bottles is done in about three days, and no off flavors. Bottles never see same temps same as primary fermentation.

Either way, fast or slow. I would advise to always pitch cooler than ferm-temp, and controlling the temp.

I've read this advice from a lot of people but I don't do it this way. Typically for an ale I ferment at 64 degrees; I'll pitch the entire starter (no decanting) directly off the stir plate at about 71 degees. When I chill the wort, I get it down to about 72 or so, such that the yeast is going into wort at the same temp it's been working in the starter. Then into the ferm chamber and down to 64.

I also do the same thing with lagers. I brew a dark lager using WLP940 (Mexican Yeast) where I pitch a 1-liter starter into wort at 71-72 degrees. It's not the recommended 2-liter starter you usually see for a lager. Once pitched, I put in the ferm chamber and dial it down to 50 degrees which takes the better part of a day to achieve. The net effect is allowing that 1-liter starter to grow into what is essentially a 2-liter starter by the time the temp gets down.

Here's the pertinent passage from White and Zanisheff's Yeast, page 134:

Other brewers like to pitch the starter as soon as the growth phase is mostly complete and the yeast are still at the height of activity. Some consider this the optimal time to utilize the yeast for the next step of a starter, or for fermenting a batch of beer. The thought is that the yeast do not have to come up from the dormant stage again, thus insuring quicker yeast activity in the beer. If you are going to pitch a starter at high kraeusen, it is best to keep the starter within 5 to 10* F of the wort temperature of the main batch. Pitching a very warm, active starter into cold wort can stun the cells, and with lager strains this can possibly affect attenuation, flocculation, and increase hydrogen sulfide production. While you can slowly cool the starter over time, it will often defeat the whole purpose of pitching at high kraeusen. Any time yeast sense a big drop in temperature, they slow down and drop out, so if you wan to pitch at the height of activity, it is better to keep the starter closer to fermentation temperatures at the beginning.


I think what this points to is that there is more than one way to skin a cat. Morrey's had my dark lager, liked it enough to brew his own.

 

[GolFisHunt]

Seems like a bit of a hot button topic, but I appreciate all the info and suggestions. Ordered the Inkbird 308, thermowell, and one of the heat wraps from Amazon. Since it was substantially less money, I ordered a dry hopping basket as well.
Thanks again.

 

[ScrewyBrewer]

Another thing to keep in mind when dealing with wider than acceptable temperature swings. When the ratio of liquid volume, in this instance wort, is less than the cubic feet of the fermentation chamber.

Case in point. With all things being equal, using the same temperature controller, heater and thermowell setup. When I have one 5 gallon batch fermenting in my chest freezer, the temperature overshoot is a lot greater than when I have two 5 batches fermenting in the freezer.