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BrewPi: Raspberry Pi and Arduino Powered Fermentation Chamber

Posted by Unknown on from the includes-kitchen-sink dept.

For the homebrew hardware nerds out there who also homebrew beer: "BrewPi is an open source fermentation controller that runs on an Arduino (for now) and a Raspberry Pi. It can control your beer temperature with 0.1 degree precision, log temperature data in nice graphs and is fully configurable from a web interface." Source code. The article has lots of photos and screenshots. The project involves rewiring the compressor's electrical connection through a PID controller, and includes both a fancy OLED display on the fridge and support for logging statistics and control over the web. If you've ever had the joy of gradually crash-cooling a lager (not too fast, not too slow), the software includes settings to effect gradual temperatures changes in the fermenting wort. Certainly fancier than a Johnson controller and a probe attached to a fermenter with a strip of insulating tape.

96 comments

  1. Do the same with a handful of transistors by Gothmolly · · Score: 1, Interesting

    Why does it have to be a Raspberry? Why do you have to control it in C? Is it because people don't teach or know how to do it the old school way anymore? Is the effect somehow less if you DONT have a fancy OLED display?

    THIS is why I cancelled my "MAKE" subscription - too much sizzle and not enough steak.

    --
    I want to delete my account but Slashdot doesn't allow it.
    1. Re:Do the same with a handful of transistors by santax · · Score: 1

      Of course it has to have a oled display. That way you can program tetris on it and tell the wife the kettle is the computer that you build yourself.

    2. Re:Do the same with a handful of transistors by afaik_ianal · · Score: 5, Insightful

      You reckon you can do temperature control in an uncontrolled environment with a handful of transistors? Keep in mind the external temperature is uncontrolled. The yeast itself generates heat within the ferment at varying (and often unpredictable) rates.

      The simplest approach you can reasonable consider for the level of control they're looking for in their environment would be a PID controller, which if memory serves me correctly will have more than a handful of transistors in it. You're going to need a pretty decent PID to handle temperature profiling, which their solution

      They're using cheap, off-the-shelf parts to solve their problem, which in turn allow them to put extra features in there like web control, and it's now much easier for anyone to do the same thing. The parts may not have existed in 1964, but you need to keep in mind The Doors aren't the only good thing to happen since then.

    3. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 0

      You are right, now we have all this awesome technology, we should definitely not bother using it! That would just be silly!

    4. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 0

      It is overkill, but not because of the displays and such. Those are great.

      I don't, however, usually join in on the whole, "zomg you coulda implemented this with discrete components in less than 12 years" douchebaggery.

      If someone is aiming for "most efficient design", at that point you buy a device off ebay.

    5. Re:Do the same with a handful of transistors by OzPeter · · Score: 3, Insightful

      Why does it have to be a Raspberry? Why do you have to control it in C? Is it because people don't teach or know how to do it the old school way anymore?

      Do you want to explain how to make a tunable PID loop out of transistors? Yes it can be done, but the commercial loop controllers I used 30 years ago certainly had their foibles. And there is a hell of a lot of useful fundamental old school control theory that can be learned in doing it the way they have. Proper manual loop tuning is just as much an education as building a circuit out of individual parts.

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    6. Re:Do the same with a handful of transistors by EvolutionInAction · · Score: 2

      Glad you're gone.

      Look, you can do it the easy way or the hard way. When tech is cheap, why not do it the easy way? And when you've got the extra power, why not go for some bells and whistles?
      And did you read the goddamn article? The guy wants to glance at his brewer and make sure it's still doing what it should. Should he make it beep morse just because he can?! Seriously, what kind of idiot would build something like this without a display?

    7. Re:Do the same with a handful of transistors by dohzer · · Score: 0

      Yeah, finally something other than XBMC for all those sheep to use their dusty Pis for!

    8. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 3, Informative

      According to the comments here: http://hackaday.com/2012/10/01/brewpi-is-a-raspberry-pi-in-charge-of-beer-fermentation/

      >The Pi is a bit too unstable to be trusted with direct control over the fermentation. The slave controller runs all the control algorithms, the Pi is for interfacing and data logging.

    9. Re:Do the same with a handful of transistors by jcr · · Score: 3, Interesting

      Is it because people don't teach or know how to do it the old school way anymore?

      Got it on the first guess. Hell, I'd be surprised if 2% of /. readers can even read resistor color codes.

      Of course, that being said, it's probably less work to calibrate a computer controlled sensor and cooler than to achieve the same precision with thermistors.

      -jcr

      --
      The only title of honor that a tyrant can grant is "Enemy of the State."
    10. Re:Do the same with a handful of transistors by honkycat · · Score: 4, Insightful

      Why does it have to be a Raspberry? Why do you have to control it in C? Is it because people don't teach or know how to do it the old school way anymore? Is the effect somehow less if you DONT have a fancy OLED display?

      Why? Because these methods are objectively better than the old way. And I say this as someone reasonably experienced in the old school way.

      The controller is far more sophisticated than a simple PID loop, even if you ignore the ability to log the temperature history, store profiles, query the status remotely, etc.

      The OLED display isn't necessary, but it's actually a helpful, useful feature to be able to display the status of the system clearly and unambiguously.

      And good luck implementing this "the old school way" in the same period of time as someone using these tools could do it.

      It doesn't have to be a Raspberry Pi or Arduino with a spiffy display, but there's no glory in doing things the hard way. There's educational value in it, and in knowing the basics, but a system that works doesn't benefit from having been hard to build.

    11. Re:Do the same with a handful of transistors by anubi · · Score: 4, Interesting

      I guess if you consider the problems you would have calibrating an analog version, along with the display interface, the digital stuff has become more practical than the old analog stuff we grew up with. Did you forget all those trimpots we always had to design in because we never knew the exact parameters of our parts?

      Those old analog panel meters are now quite expensive. As well as being fragile, and never were much better than 2% accurate. The cheapest 3 1/2 digit display you get today blows them out of the water.

      Personally, I enjoyed this article - as I build a lot of heat transfer controllers - and I find it very interesting what others are doing.... Not to say I would do it the same way, but others often find some way around a situation that has stymied me in the past.

      I am very interested in when people start controlling compressor speed via variable-speed three-phase drives. Some washing machines already use these pancake-like motors to completely eliminate the transmission, controlling the motor speed and direction directly from a microcontroller so as to seamlessly shift the motor function between agitate and spin. I have been waiting with baited breath for a refrigeration compressor made in that manner so I can optimize the refrigeration process for whatever heat transfer I can get into the evaporator coil and out of the condenser coil. The only control point I now have is either flat all-or-nothing from the compressor and limited control of the thermal expansion valve. With finer control of heat exchanger temperatures, I can control not only air temp but also the humidity.

      Articles like this constitute a design snippet to show a usable part of a larger system.

      --
      "Prove all things; hold fast that which is good." [KJV: I Thessalonians 5:21]

    12. Re:Do the same with a handful of transistors by Formalin · · Score: 1

      It's a lot easier to make them with comparators or opamps as opposed to discrete transistors.

      They're pretty good at P, I, and D. Kinda what they were devised for... op[erational] amplifier. Analog math / computing.

      Can be fairly simple circuits, but tuning takes some work (not that it doesn't in digital, either). Digital has the advantage of fitting a wider range of applications without needing physical component changes and so on.

      I kind of feel sad when I see people replacing a mechanical thermostat, or simple analog circuit for the same purpose, with a much more expensive digital version that is optionally buggy and less accurate. (not saying that's what the article or summary are about, as I haven't read them).

      I love microcontrollers, but it seems like analog is going to be a lost art at this rate.

    13. Re:Do the same with a handful of transistors by Formalin · · Score: 1

      Having read the thing now, digital is the way to go in this instance.

      I'd have done it cheaper though :-p

      I still see things all the time that really ought to be analog, which is what I was talking about anyway.

    14. Re:Do the same with a handful of transistors by ncc74656 · · Score: 4, Interesting

      That sounds a bit fishy. A Raspberry Pi can't keep up with switching a fridge on and off to keep temperature in a range? That beggars belief. I have an Apple II bit-banging a 1-Wire temperature sensor and clock and toggling a relay on and off for the same purpose. If a 1-MHz 6502 can run a fermentation fridge, I'd think a Raspberry Pi would be more than up to the task. I'm pretty sure there's a 1-Wire USB interface available that would let the RPi use the same sensor I'm using, with less overhead.

      --
      20 January 2017: the End of an Error.
    15. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 2, Informative

      Elco here. The raspberry pi is easily fast enough, but it would crash on me sometimes. Just hang and require a reboot. A microcontroller just doesn't crash.

    16. Re:Do the same with a handful of transistors by AC-x · · Score: 4, Informative

      The Arduino does the temperature control (as that's what microcontrollers are good for) and the Pi is there to add a nice display and web server (as that's what a mini SBC is good for), seems like using the right tools for the right jobs to me. If you don't want a fancy display you could just use the Arduino part and skip the Pi.

    17. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 3, Funny

      Dude do you know how many transistors you can fit in your hand nowadays?

    18. Re:Do the same with a handful of transistors by fuzzyfuzzyfungus · · Score: 2

      The Arduino does the temperature control (as that's what microcontrollers are good for) and the Pi is there to add a nice display and web server (as that's what a mini SBC is good for), seems like using the right tools for the right jobs to me. If you don't want a fancy display you could just use the Arduino part and skip the Pi.

      In that vein, it's worth noting that an entire RPi sells for less(sometimes about the same, depending on distributor) than the most common W5100-based Arduino ethernet shields, while being markedly more powerful and having convenient features like USB host support and some I/O pins of its own. This probably helps explain some of the recent popularity of 'Arduino+RPi' projects where the RPi is, perhaps, a bit on the overkill side from a purely technical perspective...

    19. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 0

      You're going to need a pretty decent PID to handle temperature profiling, which their solution

      You accidentally the solution!

    20. Re:Do the same with a handful of transistors by EmagGeek · · Score: 1

      Agreed. This same thing can be accomplished with $2 worth of op amps and passives, with no software to be buggy.

      When the only tool you have is a hammer, everything looks like a nail.

    21. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 0

      I'm color blind you insensitive clod!

    22. Re:Do the same with a handful of transistors by dedmorris · · Score: 1

      Hell, I'd be surprised if 2% of /. readers can even read resistor color codes.

      BBROYGBVGW - For political correctness, I won't share the mnemonic I used 30 years ago. Now get off my lawn.

    23. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 0

      Hell, I'd be surprised if 2% of /. readers can even read resistor color codes.

      BBROYGBVGW - For political correctness, I won't share the mnemonic I used 30 years ago.

      Now get off my lawn.

      Bad Boys Rape Our Young Girls But Violet Gives Willingly

    24. Re:Do the same with a handful of transistors by Sqweegee · · Score: 1

      I built an analog PID controller years ago in an industrial controls course exactly that way using opamps. We only used it to keep a couple of servos aligned but it could have been adapted to anything.

      Tuning was a pain, as it was part of the whole point of the exercise we needed to swap out the individual resistors, caps, and inductors to achieve the tune values we had calculated for a proper response as well as specific improper responses each stage could cause. Even the small leakage in the capacitors caused some drifting until we switched from electrolytic ones to ceramics.

      I recently made similar chambers to this brewing one using a little programmable PID controller and a couple of relays to replace the mechanical thermostat on a fridge so we could get tighter temperature control and a wider operating range (0-35 C). The $200 controller was overkill for basic control but we needed programmable temperature profiles too. Next time I'll have to look into this type of controller.

    25. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 0

      Get Some Now

    26. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 0

      Microcontrollers can glitch from transients and probably even cosmic rays *grin*, but they can be mitigated by using transient-hardened software techniques and watchdog reset timers.

    27. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 0

      I simple PID like device takes around 8 transistors and several resistors. Its not a true PID controller but it will certainly appear like one to the ignorant outside observer unless you have a truely volatile environment to control, which this isn't.

    28. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 0

      Could have done it all on the Arduino, it has no problem serving web pages and displays if you add a wiznet ethernet port to it.

    29. Re:Do the same with a handful of transistors by Tassach · · Score: 1

      Why do you need electronics at all?

      All you need to brew alcohol is watertight container of moderate size, a sugar-rich solution, and a teaspoon or two of yeast. People were doing it for thousands of years. There's even some evidence to suggest that the neolithic transition to sedentary farming was motivated by the desire to have a large surplus of grains available to ferment.

      --
      Why is it that the proponents of "one nation under God" are so eager to get rid of "liberty and justice for all"?
    30. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 0

      Those washing machines have been around for 20 years now. Fisher & Paykel SmartDrive was the first AFAIK. Re compressors, the marketing name for VFD control is "inverter", as in "inverter heat-pump", etc.

    31. Re:Do the same with a handful of transistors by bonehead · · Score: 1

      You don't "need" electronics. Particularly if all you care about is that the final product have some alcohol content.

      Something like this is handy for when you want to produce the best product you can, and even more importantly, when you want to be able to consistently produce a beer that tastes the same from batch to batch.

      Fermentation temperatures can have a large effect on the taste of a finished beer. Even from the exact same recipe you can have very different tasting products from summer to winter if they're fermenting in some random closet in your house.

      Having precise temperature control means being able to produce the exact same product, reliably, over and over again.

    32. Re:Do the same with a handful of transistors by denvergeek · · Score: 1

      For lagers, as opposed to ales, you generally need slightly lower temperatures than your ordinary household ambient temperature. It's difficult these days to find a friendly, local cave with the proper temperature.

      The common home brewer solution to this problem, absent a sufficiently cool basement, is to use a chest freezer with an aftermarket temperature controller. The temp controller is plugged into the wall, the chest freezer plugs into that, and a probe goes inside. It's a reasonably cheap solution for home lagering or keg dispensing.

    33. Re:Do the same with a handful of transistors by Anonymous Coward · · Score: 0

      Got it on the first guess. Hell, I'd be surprised if 2% of /. readers can even read resistor color codes.

      I bet you meant to also say "without an app on their smarphones". :)

  2. multiple control points by exabrial · · Score: 5, Interesting

    I'd be interested in multiple control points... I've started to do pressurized fermentation once the gravity of the beer of approaches the final gravity. This carbonates the beer without a secondary fermentation, and reduces risk of introducing oxygen and contamination into the beer. If the system could electronically monitor specific gravity then seal the airlock, but blow off any excess over 10psi... would be awesome!

    1. Re:multiple control points by cheater512 · · Score: 1

      Find a sensor that does that, plus a suitable valve, and it can't be very hard to add that.

    2. Re:multiple control points by Anonymous Coward · · Score: 0

      Thats what Corny kegs are for.

    3. Re:multiple control points by Anonymous Coward · · Score: 0

      Some links please good sir! I've had several batches that tasted awesome right before I added priming sugar, but ended up down the drain despite multiple tastings over up to a year once priming sugar was added. I'm cursed it seems and if I don't need priming sugar I'll be very very happy.

    4. Re:multiple control points by exabrial · · Score: 1

      Yah that happens to best of us... sorry to hear that. Priming sugar has to be measured by weight, carefully boiled, and mixed into the freshly fermented beer. It's delicate process that can go wrong in a ton of ways.

      Do you have a kegging system? If so, try forced carbonation. Google for more information, but here's the basic process: Chill your beer. Purge/Burp the keg several times to get a C02 atmosphere. Set your regulator to 30psi. Slosh the beer a few times. Leave for 12 hours. Set to final pressure (usually 8-12psi, depending on your beer style). Leave for 5 days. Enjoy carbonated beer.

      I don't have a lot of good info on pressurized fermenting other than what I've read on homebrewtalk. They technique I've read is to watch the gravity carefully. As it comes close to the final gravity (~3 days before end of fermentation), you let it build ~10-15psi of pressure. I've tried mechanical valves meant for air compressors with no luck. I think an electronic system with an emergency mechanical backup would be a good design.

    5. Re:multiple control points by Anonymous Coward · · Score: 0

      This technology looks to be a boon for folks trying to get by in places like Saudi Arabia where Heineken doesn't distribute and homebrew rules the day. As I recall, if a colleague walked by your house and the (noisy) air conditioner (sticking out the window) stopped and called you to tell you about it, you knew to do something quick(!). Because if the house overheated and the beer exploded, the smell would get you busted in a big way. This cheap technology raises quality while reducing risk; presumably even sending alarm messages, just-in-case.

    6. Re:multiple control points by afaik_ianal · · Score: 2

      The valve is the easy bit (if you don't mind manually switching a tap on in response to an alert).

      The sensor is not so simple. Even if digital hydrometers were cheap and easily available, you'd need to find a way of mounting it inside the fermenter such that you're not going to create a haven for bacteria (hint: any kind of non-smooth surface inside the fermentation vessel is a haven for bacteria).

      I've heard of people using ultrasonic transducers for measuring the gravity of fluid in a pipe, but it sounds like a lot of work.

    7. Re:multiple control points by norpy · · Score: 2

      Why open a valve electrically?

      There are valves you can get from 0.25psi upwards that will do it mechanically, and i'm sure there are digital probes that will measure specific gravity. If not you could make one with a float, a webcam and some crude image processing.

    8. Re:multiple control points by Guido+von+Guido+II · · Score: 1

      It could be your bottling technique or equipment as well.

    9. Re:multiple control points by FictionPimp · · Score: 1

      You can even do forced carb even easier. Find a nice Carbonation chart ( such as http://www.kegoutlet.com/media/uploads_ckeditor/Carbonatin-Chart.jpg ) and set your pressure to the desired volumes of CO2 for the temp of your keggerator/keezer. Now wait 1-2 weeks (which is almost always a good idea with any beer) and you should have perfectly carbonated beer.

      Sloshing will carb it up faster, but you still have to wait for the beer to clear and you risk foaming, but it's good for a hurry.

    10. Re:multiple control points by Doctor+Memory · · Score: 2

      LOL. "Carefully boiled"? What's that, in an ASTM-certified 18/10 stainless steel reaction vessel with distilled water when the ambient air pressure is no more than 30.05 using a thermal introduction profile not to exceed 10deg/sec? I just dump two cups of tap water in a small saucepan, heat it to boiling, dump in my priming sugar, and stir until dissolved (takes about twenty seconds). Then I dump it into my (freshly-sanitized) bottling bucket, rack my beer onto it, give it a quick stir with a sanitized stainless spoon, then bottle. It's really pretty difficult to screw this stuff up.

      Sure, you can agonize over how many volumes of CO2 the BJCP claims are "proper" for your beer's style, and what kind of fermentables will either compliment or at least not intrude on your beer's flavor, but that's optional. It's all beer in the end. Relax!

      --
      Just junk food for thought...
  3. This, my friends, by tpstigers · · Score: 5, Funny

    is what technology is for.

    1. Re:This, my friends, by Anonymous Coward · · Score: 1

      Bah, my girlfriend has had a yeast fermentation chamber in her Pi for many years now, without using any fancy technology.

      -- Ethanol-fueled

    2. Re:This, my friends, by bondsbw · · Score: 1

      And completely free-as-in-beer.

      --
      All my liberal friends think I'm a conservative, all my conservative friends think I'm a liberal.
    3. Re:This, my friends, by madhatter256 · · Score: 2

      I just don't like the term "BrewPi".

      Most beer drinkers will read it as "BrewPee"

      No thanks.

      --
      Previewing comments are for sissies!
    4. Re:This, my friends, by Anonymous Coward · · Score: 0

      On that note: http://vimeo.com/21148965

  4. Still waiting by TheRealMindChild · · Score: 1

    Still waiting for my Gertboard

    --

    "When life gives you lemons, don't make lemonade. Make life take the lemons back!" -- Cave Johnson
  5. Controller Algorithm by OzPeter · · Score: 1

    For something like a fridge that has a lot of thermal mass I'd be tempted to ditch a PID approach and go for a PD controller. Using the PD configuration I've achieved great results with ovens heating large steel canisters and having them closely follow ramping and soaking profiles.

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    1. Re:Controller Algorithm by Anonymous Coward · · Score: 0

      At some point, you are going to either simulate or by luck or follow a guideline to come up with the coefficients for the control loop.
      A PID controller becomes a PD if the coefficient for the integrator is set to zero. ;)

    2. Re:Controller Algorithm by Anonymous Coward · · Score: 0

      Elco here.

      Fermentation is an exothermic process. So if you don't have an integrator, you will have a steady state error. The integrator is only active near steady state conditions (low derivative, close to target)

  6. Raspberry Pi or Android Arduino? by kriston · · Score: 1

    I'm looking in my local RadioShack and I noticed the newer Android-powered Arduino.

    Since I'm not seeing Android on the Raspberry Pi, what would be the advantage of the Android Arduino over the Pi besides the much higher price and Android operating system? The Pi already has a fairly useful Debian with X Windows which I didn't see on the Arduino.

    --

    Kriston

    1. Re:Raspberry Pi or Android Arduino? by drinkypoo · · Score: 0

      I'm looking in my local RadioShack and I noticed the newer Android-powered Arduino.

      I haven't noticed this. What are you talking about?

      Since I'm not seeing Android on the Raspberry Pi, what would be the advantage of the Android Arduino over the Pi besides the much higher price and Android operating system?

      No idea. The Pi is supposed to have Android, but they refuse to release it! They claimed the only problem with ICS was sound, but it's been months since that claim and there's been no release, no source, no howto, no nothing. This is badly, sadly disappointing. I thought Raspi was supposed to be an open platform (binary blobs aside) but there's been sadly little openness so far. It's very much been "when we're ready" and no status updates whatsoever. Tons of people want to help! The announcement thread is just full of people saying they'd like to. But what it's not full of is status updates.

      In short, at this point I would go to Newegg and drop $60 (with free shipping) on the VIA APC, if you want Android. I have no idea what you're talking about when you say "Android Arduino". I know there's some Arduinos meant to be used with android devices...

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    2. Re:Raspberry Pi or Android Arduino? by RobertLTux · · Score: 1

      he is most likely talking about the 276-0129 (retailing at $84.99) i would say very few RadioShacks have this IN STOCK but all of them should be able to order it Direct2U.

      (speaking as a former Tandy/Radio Shack employee)

      --
      Any person using FTFY or editing my postings agrees to a US$50.00 charge
    3. Re:Raspberry Pi or Android Arduino? by drinkypoo · · Score: 1

      Oh, you mean the ADK. Yawn. Arduino with Android connectivity and an extra-big price tag. I thought it might have been something relevant, but it's certainly not an Android-powered Arduino.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
  7. I hate beer ... by js33 · · Score: 2

    Can this ferment viili or filmj:olk?

    1. Re:I hate beer ... by Anonymous Coward · · Score: 0

      Short answer is, sure.

      This is both a software interface and the controller to a fermeter / bioreator, which adjusts temperature based on sensor configuration. For things which only need temperature control, this is fine, but if you require adjustments from any other loops, you'll have to program them yourself. For instance, in brewing, the fermentation stage lasts many weeks and is self contained at that point. Yeast slowly metabolize substrates in the media and produces stuff like ethanol and CO2. The media preparation, boiling the wort, introducing malts, single or double hopping, are all done manually. So can this be used to simplify the fermentation of the things you listed? From reading about them, sure, on a bench scale.

      It looks like the fermentation times are pretty short and not dependent on fine temperature control, but you might add a pH probe to log growth. I don't see a lot of need for a controller for small scale though, since it's basically just milk in buckets. Try it out anyway, and post back here about how you set up your project.

  8. Johnson controller? by 2themax · · Score: 1

    I know about PID and fuzzy, but what the hell is a Johnson controller?

    1. Re:Johnson controller? by tapspace · · Score: 1

      http://www.funnyordie.com/videos/2c5b4742c7/snl-celebrity-jeopardy-3-20-99

    2. Re:Johnson controller? by Unknown+Lamer · · Score: 1

      A cheap and easily available analog temperature controller that a lot of homebrewers use with repurposed fridges. Or, genericized, any external temperature controller that you hack onto a fridge for keeping femermenters or kegs at the proper temp.

      --

      HAL 7000, fewer features than the HAL 9000, but just as homicidal!
    3. Re:Johnson controller? by Anonymous Coward · · Score: 0

      Of course you know what a Johnson controller is. Every guy gets one on his wedding day.

    4. Re:Johnson controller? by hovelander · · Score: 2

      For my Keezer build I looked into a Johnson controller, but decided to go with one of the cheaper and better Chinese eBay temp controllers for 25$.

      http://www.homebrewtalk.com/f51/ebay-aquarium-temp-controller-build-163849/

      Dirt cheap and reliable. I was looking all over for an arduino build like this though, because I would love to log the temps.

      Made my first lager with the cheap Keezer, a little GE that can hold 4 Corny Kegs, and am in homebrew heaven. Make a Homer Love/Drool noise if you know what I mean, my homebrew brothers and sisters!

      http://www.homebrewtalk.com/f51/ge-7-cf-fcm7suww-keezer-conversion-192208/

      I bottled exactly once and ran straight to kegging. Washing bottles is purist, sure, but egads does it suck. And having an 80lb CO2 tank connected to what will be a standing desk that dispenses 4 different beers? Goddamn I love the art and science of homebrew.

      And by the way, InBev? Fuck you. Same thing to all the prohibition era, rice beer holdovers from when it wasn't legal to brew at home. Damn old ladies and their axes...

    5. Re:Johnson controller? by hovelander · · Score: 1

      Your wife has only one hand? Empathy to you and her, my friend.

      Whassat? Oh, OH!

      You mean the Whole Lady Unit. Gotcha, now... : /

  9. From Utilitarian to Amusing to Delicious by Penurious+Penguin · · Score: 1

    A friend and I make fermented apple cider, but very primitively. Basically, we buy a glass gallon of unfiltered apple-juice, an airlock, a packet of champaign yeast, and some suitable sugar. We then take a few or so cups of the apple-juice and blend it with the sugar, bring it to a simmer, add the yeast, stir it vigorously, and pour it back into the original glass bottle, then finally attach the airlock/CO2-indicator. After about one week at approximately 76 degrees-or-less, we have a pretty good preservative-free cider, which is at least 5.0-ish percent alcohol. However, tolerable as it be, it's admittedly not exquisite. Perhaps it could be improved with a little techno sauce.
    My buddy brews his own beer by the gallons in Aussiland. I know his methods are also primitive. And I should mention the super-outrageous prices for Australian beer, too! Maybe home-based brewing is now accessible enough to make a new market for quality, affordable beer.

    --
    Forward! -- Emperor Norton, 2012
    1. Re:From Utilitarian to Amusing to Delicious by mug+funky · · Score: 1

      aussie excise tax on alcohol is 75 bucks per ethanol litre.

      putting that in perspective, if you're making a wine in a 30 litre fermenter, you'll be using about 5 kg of fermentables. this will yield about 4.5kg of ethanol, which will run you about 428 bucks of excise for 6 bucks worth of ingredients.

    2. Re:From Utilitarian to Amusing to Delicious by Doctor+Memory · · Score: 1

      take a few or so cups of the apple-juice and blend it with the sugar, bring it to a simmer, add the yeast, stir it vigorously, and pour it back into the original glass bottle

      Wait, you're adding yeast to hot cider? When brewing beer, you have to get your wort temperature down below 80 before you add your yeast. Sounds like it's working for you, though, maybe champagne yeast is tougher stuff than regular brewer's yeast.

      --
      Just junk food for thought...
    3. Re:From Utilitarian to Amusing to Delicious by Anonymous Coward · · Score: 0

      Champagne yeast is damn near unkillable and produces a neutral flavor at a very wide temperature range.

      It's not that great at fermenting maltose, though. For beer I prefer US-05; it's another very forgiving strain.

    4. Re:From Utilitarian to Amusing to Delicious by cayenne8 · · Score: 1

      putting that in perspective, if you're making a wine in a 30 litre fermenter, you'll be using about 5 kg of fermentables. this will yield about 4.5kg of ethanol, which will run you about 428 bucks of excise for 6 bucks worth of ingredients.

      Is this for the home brewer?

      Are you saying over there..they charge you all this tax for alcohol, on raw ingredients that 'could' be used to make DIY home brewed alcohol?

      If so...wow....

      Here in the US...the ingredients you buy are only subject to the usual sales tax any item sold is subject to...but, if you're brewing for personal consumption....there's no additional fees or taxes or licenses....

      --
      Light travels faster than sound. This is why some people appear bright until you hear them speak.........
  10. Commercial product by Wakkow · · Score: 1

    I ran across the BrewBit. By the looks of the blog, it's pretty far along (photos of the circuit board) but I have no idea what it's going to sell for.

  11. Primitive Cider Can Still Be Amazing by Unknown+Lamer · · Score: 2, Interesting

    You can definitely make great cider that way (I've done it!). Instead of Champagne yeast, try Cote Des Blanc or an English ale yeast to get a bit of extra complexity (Champagne yeast is really neutral... an estery yeast really helps in a cider), and bump the gravity up to around 1.070-80 (maybe even 1.100 if you want to make an Applewine instead). You have to let it ferment for around 3 months (and rack it at least once! Sulfites are your friend), but the end result is pretty great with not much more effort than "try to forget that it exists for a while".

    Starting off that way, I've gotten into making a lot of Cysers (think mead, but with apple cider instead of water diluting the honey)... super simple brewing process compared to beer, but the whole "it really does only start tasting great at 12-18 months after you made it" part is so painful (well, it's certainly good well before then, but once you've tasted a wine you've let properly age you realize how much you were missing... ignorance, unfortunately, proves yet again to be bliss). I'm on my third year so I have a reasonable stock built up, but boy was it hard at first...

    --

    HAL 7000, fewer features than the HAL 9000, but just as homicidal!
    1. Re:Primitive Cider Can Still Be Amazing by Penurious+Penguin · · Score: 1

      Excellent advice; I will definitely apply it. But apple honey mead, absolutely wicked! No, I couldn't wait for that. I would be counting bubbles until I went insane. Maybe if I could leave it in a different State while it aged.

      --
      Forward! -- Emperor Norton, 2012
    2. Re:Primitive Cider Can Still Be Amazing by Anonymous Coward · · Score: 0

      Cysers (think mead, but with apple cider instead of water diluting the honey)

      I've made this last year and I didn't even know it had a name ! Mixed apple juice and honey and fermented with beer yeast. Decent is a little dry. Haven't tried it in a few months. Maybe it's aged better now. I must say that I shouldn't be surprised as I'm pretty sure everything related to alcohol has certainly been tried long ago. Just like for sex.

      (anon because already moderated)

    3. Re:Primitive Cider Can Still Be Amazing by mug+funky · · Score: 1

      wifey has a sulphite sensitivity. if i don't want to spend the night scratching her back, preservatives are out.

      makes things tricky - gotta be much more sanitary and also not leave things too long. fast ferments are good though (i'm trying my hand at a Caribbean rum now, as those ferment out in 3 days), but tend to limit the flavour profiles you can get.

    4. Re:Primitive Cider Can Still Be Amazing by cayenne8 · · Score: 1

      Excellent advice; I will definitely apply it. But apple honey mead, absolutely wicked! No, I couldn't wait for that. I would be counting bubbles until I went insane. Maybe if I could leave it in a different State while it aged.

      Nah...just make 2-4 batches each time you make it....drink 2 batches....put two batches back.

      When each batch is about ready...brew 2-4 more batches...that way, you are drinking the young stuff (to satisfy your thirst), but you are also putting stuff back...and if brewing every couple weeks...you'll have stuff coming out weekly to drink and put up, while others are fermenting....etc.

      And hey, I used to have fun brewing with friends...we'd pay 'homage' to the old batch...by drinking it whilst brewing the new batch.

      --
      Light travels faster than sound. This is why some people appear bright until you hear them speak.........
    5. Re:Primitive Cider Can Still Be Amazing by cayenne8 · · Score: 1

      (i'm trying my hand at a Caribbean rum now, as those ferment out in 3 days),

      Can you go more into the 'caribbean' rum thing? Are you saying you're fermenting...the distilling something into rum?

      Where are you living....I don't know of any countries or US states really....where distilling, even for personal use, is legal.

      Not that I'm not wanting to try it myself...hope to soon, guessing that a small batch set up won't draw attention...but just curious as to what you're doing...?

      --
      Light travels faster than sound. This is why some people appear bright until you hear them speak.........
  12. My digital thermometer has 0.1 degree precision by Anonymous Coward · · Score: 0

    And it only cost 80 cents shipped from China. Its accuracy isn't better than +-1 degree Celsius though. Does your yeast really care more about a constant temperature than about the right temperature?

    (Questions? http://www.mathsisfun.com/accuracy-precision.html)

  13. Slightly overpowered for the task? by Anonymous Coward · · Score: 0

    You can do much the same stuff with just an Arduino. No fancy graphs, but it does Tweet. https://twitter.com/fermtherm

  14. The missing link by Anonymous Coward · · Score: 0

    After the poo machine a Brew Pee was right at the corner.
    https://www.youtube.com/watch?v=VdlLBWymnUA

  15. Both an Arduino *and* a Raspberry Pi ? by benjamindees · · Score: 2

    This seems like overkill. If you just want a web interface, there is an Arduino library that will allow you to establish a SLIP connection over USB to connect to the Arduino via a webbrowser, no ethernet shield required: SerialIP. It does take up a bit of memory, though, which leads to the next suggestion...

    How did you max out the program memory on your Arduino? Why on earth would you use 16 bits (0.001953125 dC precision) to store temperatures, when your thermometer only has +/-0.5 dC resolution? Does it really matter that you turn on your refrigerator compressor at the exact nanosecond it needs to come on?

    --
    "I assumed blithely that there were no elves out there in the darkness"
    1. Re:Both an Arduino *and* a Raspberry Pi ? by Anonymous Coward · · Score: 3, Informative

      Elco here,

      The Arduino could by itself send some simple values to a server. It could not provide a fancy interface. The thermometer has ha 0.0625 resolution, a 0.5 deg absolute accuracy. I am filtering the temperature data and need the higher resolution for the control algorithm. If you don't filter, and your sensor jumps from 20.000 to 20.0625, what's the slope?

      The program memory is full because of the 16 bit variables and that they are all configurable from the web interface. And no for brewing you don't NEED to control the temperature with 0.1 degree precision.

    2. Re:Both an Arduino *and* a Raspberry Pi ? by benjamindees · · Score: 1

      Okay, take this with a grain of salt since I'm not really an expert on web design. But it should be possible to write your web interface in Javascript, store it locally, and use it to communicate via JSON with the Arduino over USB.

      If you're considering producing an Arduino shield, it's not too costly to add a bit of memory as well for data logging and storage.

      Just something to consider. It seems like it would make your design cheaper and more robust, for the cost of a bit of programming.

      --
      "I assumed blithely that there were no elves out there in the darkness"
  16. Bread by benjamindees · · Score: 1

    Also, I think you should generalize this project to include maintaining a bread yeast culture.

    --
    "I assumed blithely that there were no elves out there in the darkness"
  17. Why the low power chips by Chrisq · · Score: 1

    If they used a pentium they could warm the fermentation vats too ..... now I wonder if I could patent the first beer-cooled data center.

  18. I love it by Xenna · · Score: 1

    I love it, really, but has anyone else noticed that using a Raspberry Pi (instead of any Linux platform at all) is the greatest way to get publicity for your computer controlled hardware project?

    Brewing controlled by an HP netbook would never have made the headlines.

    1. Re:I love it by benjamindees · · Score: 1

      Meh, it is kind of a cool platform, in theory. For $25, being able to control some GPIO pins, connect via ethernet and USB, and display info on a TV are nice features.

      --
      "I assumed blithely that there were no elves out there in the darkness"
  19. The 90's called by Anonymous Coward · · Score: 0

    They want their $10 uC projects back.....

    Srsly, why the hell does anyone need a SoC running *nix to implement this? Hobby electronics is going the same way as coding, with an ever increasing trend towards bloated abstractions from reality and a failure to ever learn the basics.

  20. Basic Experimental Engineering Research = BEER by jkinney3 · · Score: 2

    BEER is good. BEER should be studied in school. BEER should be required for graduation. BEER should be in the home. BEER should be promoted for the betterment of society. BEER is good for everyone of all ages.

  21. 0.1C accuracy by EmagGeek · · Score: 1

    Accuracy has nothing to do with which processor you choose or which architecture runs your control software.

    It has everything to do with the design of your plant and the tuning of your PID loops.

    You could control a well-designed brew plant to 0.1C accuracy using a bunch of op-amps if you wanted to. A brew plant function just isn't going to be so fast that you need any kind of horsepower or complexity to run it.

    1. Re:0.1C accuracy by Anonymous Coward · · Score: 0

      It ain't "accurate" at all - the sensors are good to about +/-1.5 degrees

  22. It might only be able to make mead, but... by Hillgiant · · Score: 2

    Imagine a beowulf cluster of these.

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    -
  23. Good way to ruin your refrigeration compressor by Anonymous Coward · · Score: 0

    There's a reason refrigerators and freezers don't maintain the temperature to within a fraction of a degree. Today's electrronics are certainly capable of doing so, and cheaply enough.

    However, if you cycle a compressor on and off rapidly it can cause the compressor to fail prematurely. Experience has shown that a few degrees' worth of temperature fluctuation doesn't cause any problems, and it doesn't shorten the life of the compressor.

    Keep your Ranco or Johnson Controls unit and use them and you will still have great home brewed lagers. Just pay attention to the gentle temperature drop and make sure you do the diacetyl rest before lagering it for a few weeks or so.

    If you really want to build a controller and have LEDs blinking and an LED (or LCD) readout, set it to have a temperature differential of 3 or 4 degrees F. You can always add additional blinking LEDS in different colors if you want it to look high-tech using a 555 timer IC to control them.

    (I'd sign in but my password manager is at home and I'm not, so I guess I'm an anonymous coward for now.)

    1. Re:Good way to ruin your refrigeration compressor by Cpt_Kirks · · Score: 1

      While a neat setup, this is a bit of overkill. I use a Johnson to control my fermentation chamber, with a digital thermometer for precision checking inside.

      Just finished fermenting 13 gallons of Bavarian Amber Lager. It's all in kegs in my backup Keezer/Lager chamber lagering for another six weeks now.