Fermentation generates heat?

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kinjiru

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Hi guys,

I'm fermenting a Duvel look a like beer and I've noticed that the fermentation temperature was 4-5 degrees higher than the room temperature. I can only assume that the fermentation process generates heat.

After 2 days bubbling like a AK-47 with unlimited ammo (sugar candy has this effect :D), the temperature came down to room temperature.

Has any of you guys experienced this situation?

Regards,

Rui
 
Fermentation always generates heat, it's thermo-elastic .... Always be careful because if you don't have a fermenting chamber you could be fermenting a bit high... I like to ferment on the low end of the scale because of the heat produced by my fermentation... If you do a perfect starter and dump it into the wort it's like a BOMB ..... It will roar like a lion and heat up like a furnace... Keep an eye on the room temp before pitching and add 5 to 8 degrees more, and then ask yourself am I busting the trmps here !!

Cheers !!
 
Fermentation always generates heat, it's thermo-elastic .... Always be careful because if you don't have a fermenting chamber you could be fermenting a bit high... I like to ferment on the low end of the scale because of the heat produced by my fermentation... If you do a perfect starter and dump it into the wort it's like a BOMB ..... It will roar like a lion and heat up like a furnace... Keep an eye on the room temp before pitching and add 5 to 8 degrees more, and then ask yourself am I busting the trmps here !!

Cheers !!

What in the hell are you brewing that roars like a lion and heats up like a furnace? Aluminum cans?
 
Many brewers report that their usual fermentation regimine where temperateure control is available, is to begin fermentation at the lower end of the published range and ramp up toward the end. This is because the fermentations does the opposite: fresh yeast with large quantities of fermentatles (at the beginning) produce vigorous fermentation and high levels of heat. As the fermentables taper off, the fermentations slows down and fermentation temp drops.
 
Thanks for the feedback. Yeah, I definably have to buy a fermenting chamber....

Cheers,

Rui
 
In general fermentation raises the temperature about 2-5 degrees however, with a very active fermentation I've heard of it going as high as 10 degrees over ambient temperatures. I use 6.5 gallon glass carboys as my primary fermenters because plastic buckets insulate your fermentation raising the temps higher than a glass fermenter would. Room temperature is 68 degrees (although many people keep it at 70 or more), this just happens to be the temperature many craft breweries keep their actual fermentation temps at for ales because most American ale yeasts ferment clean and fast at that temperature. Of course if you kept your ambient temperature at 68 degrees your actual fermentation temperature would be in the low to mid 70s. You may be alright in the low 70s but if the yeast is stressed for any other reasons such as underpitching because you didn't make a starter you are likely to start getting off flavors. You were probably ok at 72 degrees (although I'm not sure how well duvel yeast performs at those temps) but in the future just to play it safe I would try and keep actual fermentation temps below 70.

Ferm chambers are great because they automatically regulate the temperature but they also take up space and cost money so if you are short on either of those there are other options to control temps. The simplest way is to get a big tub (plastic 55 gallon drums cut in half work great) put the carboy in it and fill it with cold water. Then as needed rotate ice packs (plastic drink bottles filled with water work great). If you are only a few degrees high, draping an old t-shirt over the carboy and letting it hang down into the water will cause it to wick up moisture from the bucket and evaporate causing evaporative cooling and ice packs may not be needed. The t-shirt can also be used to keep light out if the bucket is not in a totally dark location. If ambient temperatures are too cold you can also warm up fermentation temps with this setup by using an aquarium heater.
 
austinb said:
.....Ferm chambers are great because they automatically regulate the temperature.....

Another thing to consider in fermentation chambers is air movement. I use a small computer fan to pull the air from the top 1/4 through a ABS elbow and pipe to blow to the bottom of the chamber. Following HVAC practice, I have the temperature sensor hanging inside this pipe to get a valid sample. I also space the bottle off the bottom so that air of the set temperature is always flowing across all surfaces of the bottle.

The hope is that the internal temperature of the wort will be within a couple degrees of the outside temperature.

Tom
 
The hope is that the internal temperature of the wort will be within a couple degrees of the outside temperature.

I'd bet that this probe placement results in wort temperatures far more than a couple degrees warmer during the first few days of fermentation.
 
Hi guys, great tips!

Austinb, I live in an apartment, so I will try your techniques you gave me :) Also, the summer is ending so I my life will be a lot easier on the months to come.

Cheers!
 
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