Post Number: 48
Posted From: 220.127.116.11
|Posted on Tuesday, January 08, 2008 - 03:41 am: ||
Given the factors of malt, yeast, hops, water and fermentation temp that determine the character of Belgians, I think that it can be arguably said that the first four can be held fairly constant with minimal effort.
Now for the fifth element. From what I've been reading, the time/temp profile during fermentation can impart considerable changes in the flavors that are created in these fantastic beers.
I may be crazy but I'd like to vary the profiles during fermentation in an attempt to get a more consistent, repeatable result or possibly direct the brew to more specific flavor profiles.
Hence my search for hardware. If anyone knows of a programmable temp controller with a food grade sensor that could be interfaced to a PC or programmed like a thermostat, will you please point me in that direction? I figure a carboy heat wrap wired through a controller to power with the sensor submerged in the fermenting beer would be fairly easy to find but it looks like I'll have to piece one together myself. I'm not much with electricity but I can follow directions (mostly).
Post Number: 397
Posted From: 18.104.22.168
|Posted on Tuesday, January 08, 2008 - 04:39 pm: ||
I use one of these controllers:
which sounds like it will do what you want. The directions say the temperature probe isn't waterproof, but I added a little hot glue and it's been underwater for the last four years or so without any problems (I've never put it in fermenting beer, just into the water in the cooling/heating bath I use). If you have trouble finding a food-grade sensor, you could try one of these thermowells:
Another (simpler) technique would be to put your carboy in a water bath, and use a submersible aquarium heater to control the temperature of the water. Given the surface area of the water-to-carboy interface, the water should be close to the same temperature as the fermenting beer.
Post Number: 223
Posted From: 22.214.171.124
|Posted on Tuesday, January 08, 2008 - 05:01 pm: ||
Interesting idea Lee, and I'm guessing that many of the primarily Belgian-style producing brewers (Unibrou for example) probably have their own temperature profiles - and I would imagine those profiles change considerably depending on yeast strain. My WAG thinking and practice of late has been to start the ferment in the low 60's and then to move it up toward 70 only when the very active phase ends. Then, toward the end (usually around day 5-8), I've been raising the temp up to about 75 to help finish it. So far I've been able to avoid the very "hot" flavors I've experienced with higher temperatures, but I've also sometimes noticed a more pronounced tartness (not a bad tartness, just a hint).
I would love to hear more of your experiments once you have some data.
Post Number: 49
Posted From: 126.96.36.199
|Posted on Tuesday, January 08, 2008 - 08:57 pm: ||
I used the aquarium heater for about 6 or so brews and it finally cracked and fell apart last month when I last broke down the system. It wasn't much of a system as the settings on the heater were not indexed and I had to monitor it twice daily to keep it in range (+/- 3-4 deg). The tub is not insulated and my house temp changes because I shut off the heat during the day. It seems that the temp of the house would cause some large swings in the temp of the bath; plus, the heater just didn't have the 'gas' to keep up some days. Also, the water hardness here created a calcified ring around the glass tube and I think created a stress riser 'cuz that's where it broke. Perhap a higher rated, non-glass unit would work better. Hence my thought process to find a robust, closed loop system that I could program with specific time/temp profiles that won't be easily affected by the house environment. Keeping an open tub of water in the house does have another downside. One night, my dog sprung the lock on my daughter's chinchilla cage and chased one of the critters around the house until it landed in the cooling jacket where I was fermenting a Belgian Trippel. Chins can't swim so the end was obvious. I think it lasnded on the sloped side of the fermenter and couldn't get a grip to stay out of the drink. My sister suggested that I call the beer "Belgian Trippel Chin".
I still haven't told my daughter that it was my fermenter tub that the animal's demise occurred in.
And yes, it is to take advantage of those periods during the fermentation process to vary the temp for different flavor profiles. I will post any significant findings.