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Nightwulf1974

Temperature rise during primary fermentation

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Hey all,

 

Underway with my new batch (Irish Stout) and just need some clarification.  I'm about 26 hours in and have a giant volcano brewing inside the LBK, nearing the lid as we speak.  The temperature hasn't really budged at all, maybe 1 degree at most during this time.  The WORT temps at the time of putting my LBK into fermentation were reading 62F and I am only seeing around 63F at this moment.  I keep reading about the temperature increases that could be anywhere from 5 degrees to even 8 degrees if I remember right from what I have read during active fermentation.

 

Question:

 

Does the temperature during this high Krausen stage ALWAYS lead to such temperature increases such as anything over 5 degrees, or can it also be a minor shift?  Is it dependent on the type of brew as well, etc.?

 

BTW, I'm reading all kinds of threads on everything so I'm doing my best to find information before asking, but these threads can become very long and information can get buried...

 

Thanks again!

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I should have been more clear, the temps are the WORT temp, via the adhesive thermometer below the Krausen line.  I don't know what the ambient temps are in the closet I am doing this in, but it's much cooler than the house which is set at 70F. 

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There's a lot of variability as to how much the temp increases during active fermentation. Last time I brewed I made 2 batches the same day and put them in the basement where it's 66 degrees. On day 2 one batch was at 68 and the other was at 76.

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I failed to clarify that as well, sorry.  My thermometer strip is below the liquid line.  FWIW, since my original posting, it has gone up another full degree or so, and the wort temp is now at around 64F/65F.  I put a bunch of paper towels around the LBK just in case I 'blow out' the lid on mine, because this Irish Stout is going bananas inside there bubbling like mad and it has literally covered the entire inside in just a few hours.  Those yeast are insane.  :o

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Another way to measure temperatures would be to purchase a digital thermometer with a probe. Similar to this one and tape the probe to the flat, non spigot side, insulated from ambient air with a washcloth or dish towel. This should give you a good representation of wort temperatures without modifying your LBK.

 

I also bought a Coleman cooler to put my LBK's in and rotate frozen ice bottles to maintain a temperature of 64-65 degrees during fermentation. During primary fermentation I rotate the ice bottles every 24 hours. During secondary fermentation I only rotate as needed. In my opinion the last four batches I've brewed were much better than the first three. 

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I'll probably get a digital thermometer for each keg eventually, but starting with a cheaper setup and these adhesive strips seem to get me in the ballpark for now.  I'm lucky that I have a nice cool closet where at least now in the winter I will have no issue keeping the temps within an acceptable range.  I'll continue modifying my setup as I go, but for now I'm using the KISS method and also the method that keeps my wife from nagging me for dipping into the checking account too much just so I can drink LOL!

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I normally brew five gallon batches split between two LBK's in my cooler. I have one thermometer taped to one LBK and use that as my control since its all the same brew. I picked my thermometer up at Walmart for eight dollars. The one I linked was just an example. 

 

Biggest investment I've made to date is purchasing an eight gallon brew pot. My next step is to purchase a six gallon glass carboy and brew six gallon batches. If I ever get my buddy into home brewing I'll sell him what I have and then upgrade for10 gallon batches and a kegging system. 

 

The rest of my process is along the KISS method, using what I have/had on hand to brew my beer. So far it's working but I'm never satisfied and always want bigger and better. 

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8 hours ago, sabres032 said:

I normally brew five gallon batches split between two LBK's in my cooler. I have one thermometer taped to one LBK and use that as my control since its all the same brew. I picked my thermometer up at Walmart for eight dollars. The one I linked was just an example. 

 

Biggest investment I've made to date is purchasing an eight gallon brew pot. My next step is to purchase a six gallon glass carboy and brew six gallon batches. If I ever get my buddy into home brewing I'll sell him what I have and then upgrade for10 gallon batches and a kegging system. 

 

The rest of my process is along the KISS method, using what I have/had on hand to brew my beer. So far it's working but I'm never satisfied and always want bigger and better. 

I'm already looking into a bigger system and I haven't even drank my first batch.  The way I see it, is if I'm wating 7-8 weeks to drink anything, I may as well be brewing more.  I live in Portland, OR so fortunately I have access to anything and everthing that involves brewing.  After a couple batches I'm definitely going bigger. 

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If you go with three LBK's then you have one coming up every week on a three week fermentation schedule. Many will condition in 3 weeks as well, some even faster, so you can have something new pretty much every week if you plan your brew schedule accordingly.

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Remember that temperature control is very important.  Size matters (cough), but if you cannot control the temperature of the fermenter, or can't cold crash it if you want to, that's not good.  It's more important how you use it...

 

Also remember that the bigger it is, the heavier it is.  Many people brew in the kitchen and then carry the filled fermenter somewhere, often the basement.  At 8 pounds a gallon, 5 gallons - plus the weight of a fermenter - can be quite heavy.

 

I use the Mr. Beer fermenters for both of these reasons - I can fit 7 of them if I wanted to in my fermentation freezer, I can fit two in my beer frig for cold crashing (if I don't want to cold crash in the fermentation freezer), and they hold 2.5 gallons when full - so they don't hurt my back.  

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1 minute ago, RickBeer said:

Remember that temperature control is very important.  Size matters (cough), but if you cannot control the temperature of the fermenter, or can't cold crash it if you want to, that's not good.  It's more important how you use it...

 

Also remember that the bigger it is, the heavier it is.  Many people brew in the kitchen and then carry the filled fermenter somewhere, often the basement.  At 8 pounds a gallon, 5 gallons - plus the weight of a fermenter - can be quite heavy.

 

I use the Mr. Beer fermenters for both of these reasons - I can fit 7 of them if I wanted to in my fermentation freezer, I can fit two in my beer frig for cold crashing (if I don't want to cold crash in the fermentation freezer), and they hold 2.5 gallons when full - so they don't hurt my back.  

Very valid points.  I may even just stock up on LBK's as you have said.  A plus to doing that is I'm not limited to drinking the same 5 gallon batch of beer and can have different varieties in smaller 2 gallon batches.  Temperature control at least during these months is not an issue, but I haven't had to battle the summer temps and will obviously need to invest in a cooler as I don't have a basement.  A/C during the summer only will help, but I will need additional cooling to keep wort at around 65F. 

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Right.  This time of year you can often find great deals at retailers liquidating their Christmas inventory of gifts - including Mr. Beer.

 

In addition, Craigslist is a great source - either gift recipients that don't want the gift and are too lazy to return it, or those that try once and give up.  Of course Mr. Beer sells extra fermenters for $10 too.  

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I know I'm shifting gears slightly here, but I have a problem that is tormenting me. I've done the research and nothing quite fits a good solution for the issue. 

My Irish stout has been fermenting for 5 days, or that's at least what it looks like. I pitched the yeast at 64~66 degrees and put it into the cooler with an ice bottle. This has been my standard practice and keeps the wort at an optimal 64 degrees for me. The next morning, I went to switch the ice bottles and noticed that all was well with fermentation by the 3/4 inch layer of krausen. I peeked at the temperature and it read ~57 degrees (quite low IMO). Leaning toward keeping the temperature steady, I switched the ice bottle and let it ride for the day. That evening, I went for my scheduled ice bottle switch, saw the krausen climbing even more, and noted the temperature was still ~57 degrees. 

I am not sure if there are any telltale signs of suspended fermentation, so I don't know if I should leave the ice bottles out for the duration or keep the temperature steady with the bottles? My best guess is that the wort would rise to no further than 68~70 degrees without the bottles, so that might be ok. 

Im just confused that, while it is winter, every other variable has been kept the same: same cooler, same place in the room, same ice bottle schedule. Has anyone successfully brewed ales at this low of a temperature? Thanks in advance!

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Sarg, is the thermometer in the fermenter, taped to the side with a dish towel insulating it or just hanging out in the cooler?

 

Last week when I brewed my High Point IPA batch I prechilled my cooler to 55 with a couple ice bottles. Pitched the yeast at wort temperature of 66 and put the LBK's in the cooler with a small ice bottle. My temperature probe is taped to the flat side of the LBK and insulated with a dish towel. Over night the reading was at 58 but I kept with the same ice schedule and by Saturday my temps were about 64-65. So far, due to my crazy work schedule, the highest temp has been 68 degrees. 

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Sabres, thanks for the quick reply. I'm using the standard stick-on thermometer on the side of the LBK, centered vertically between the liquid surface level and the bottom. It is not being covered by anything. 

I know that fermentation can happen albeit slowly, but that is pretty low. I know that I at least wanted to keep the current schedule/configuration for a full week, for accurate readings. I'm just surprised it even hit high krausen on (typical) schedule. 

Thanks again!

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I actually purchased my 2nd LBK starter kit at Target on clearance for $11.88.  They had two and I should have bought them both.  I won't most likely brew the CAL again that comes with the kit, at least as is, but for that price I still get the cleanser, some sugar drops and of course the LBK.  I looked at Craigslist and seen a few as well there which I may scoop up.

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35 minutes ago, Big Sarge said:

Sabres, thanks for the quick reply. I'm using the standard stick-on thermometer on the side of the LBK, centered vertically between the liquid surface level and the bottom. It is not being covered by anything. 

I know that fermentation can happen albeit slowly, but that is pretty low. I know that I at least wanted to keep the current schedule/configuration for a full week, for accurate readings. I'm just surprised it even hit high krausen on (typical) schedule. 

Thanks again!

 

Yea, 57 does seem low but if fermentation started you should be fine. The first couple of batches I only used the stick on thermometer, too and saw wide temperature swings. The wort fermented and the beer tasted OK but I really had no way of knowing exactly what the temperature was. My current rig is a little better and I can keep temps within a degree of two of 65. 

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15 hours ago, sabres032 said:

Another way to measure temperatures would be to purchase a digital thermometer with a probe. Similar to this one and tape the probe to the flat, non spigot side, insulated from ambient air with a washcloth or dish towel. This should give you a good representation of wort temperatures without modifying your LBK.

 

I also bought a Coleman cooler to put my LBK's in and rotate frozen ice bottles to maintain a temperature of 64-65 degrees during fermentation. During primary fermentation I rotate the ice bottles every 24 hours. During secondary fermentation I only rotate as needed. In my opinion the last four batches I've brewed were much better than the first three. 

 

So by sticking a digital thermometer with a probe to the flat side of the LBK, and cover it up with a towel, will allow me to take the temp of the wort? 

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