Digitally track your fermentation

A friend sent me this link today. Someone has built a sensor that will measure the bubbles escaping the airlock.

http://alternet.us.com/?p=1388

But bubbles really mean nothing. And some fermenters never bubble. And even if an airlock stops bubbling it doesn't mean fermentation is finished. So it's really useless.

All that work on programming something that means nothing.

It's cute, but useless in reality.

Now if he invented something that could digitally track gravity changes, THAT would be useful.

Awesome. I live and die by bubble counts--it's the surest way to know what's going on with your fermentation.

I'd better order two just to be safe.

Revvy said:

Now if he invented something that could digitally track gravity changes, THAT would be usefull.

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When I saw the thread title I thought it would be a digital thermometer that would keep track of fermentation temperatures.

I've read several times that fermentation isn't directly related to bubbles, but I'm finding it hard to get my head around it. If a yeast eats a sugar, and makes an alcohol, is it possible that it does not make a CO2? How else is it possible to ferment without bubbles?

A bubbling airlock is usually an indication of fermentation. At it's most basic , it means that there is a different pressure inside the airlock than outside. This can be caused by fermentation. It can be caused by temperature changes. It can be caused by atmospheric pressure changes. It can be caused the gases coming out of solution in the beer....
The better way to check on fermentation is the measure gravity. That will tell you if the amount of sugar in the beer is changing.

It's moronic to say that the device is useless. In the vast majority of cases, it would have at least some value indicating the status of a fermentation. However, it will never replace taking a gravity reading for certainty.

g-star said:

It's moronic to say that the device is useless. In the vast majority of cases, it would have at least some value indicating the status of a fermentation.

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Sure, but no better than what your eyeballs can already tell you. And in the end, you still have to take a reading

It's a less than perfect method of evaluating the fermentation.

You could have minor leaks in your fermenter, allowing the CO2 to escape without causing bubbles.

The rate of bubbling does not indicate what gravity your beer is.

Change in temperature can cause a change in desity, which causes a change in volume, which can make an airlock bubble, or stop bubbling, even if fermentation is continuing, or complete.

Even though an airlock may bubble, and it's good to see it bubbling, only by taking gravity readings can you accurately understand what is going on with the fermentation.

Cromwell said:

I've read several times that fermentation isn't directly related to bubbles, but I'm finding it hard to get my head around it. If a yeast eats a sugar, and makes an alcohol, is it possible that it does not make a CO2? How else is it possible to ferment without bubbles?

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And how does an airlock that may or may not bubble, or can bubble slow, or fast or not at all, can start and stop due to changes in barometric pressure, temperature, or whether or not the cat or vacuum cleaner bumped into it, help you to know how or even if a brew is fermenting at any given time? Half the time my airlocks NEVER bubble. And sometimes the lowest gravity beer will have an airlock blowoff whereas I could be brewing a barleywine that barely bubbles?


Bubbling and fermetnation are NOT the same thing. And you really need to separate the two ideas. Airlocks tell you the WHAT is happening, that co2 is or isn't getting out of the fermenter....but they aren't telling you the WHY. If it's fermenting or not, or off gassing or not. If it's done or not....

A HYDROMETER is the only indicator of how a beer/wine is doing at any given time. An airlock is purely a vent, a VALVE to release built up co2, it's not a "magic fermentation gauge."


Airlock activity is irrevelent. Just gravity points on a hydrometer.

The rate or lack of or whether or not it bubbles at all, or if it starts and stops has more relation to the environment the fermenter is in, rather than fermentation itself. All it is is a vent, a valve to let our excess gas, especially co2, nothing else. It's not a fermentation gauge whatsoever.

And the only TRULY airtight fermenters out there are if you ferment in a keg or a conical, something that can contain the pressure of fermentation.

Contrary to what you may think, neither a bucket OR a carboy with a bung is airtight. As I stated above you don't want it to be airtight, unless it's a keg or a Stainless conical, unless you like beer/ wine on your ceiling.

The airlock is one of the most superfluous things in brewing, that new brewers seem to put the most stock in.

I've said it over and over and trolls like to try to get me, or even accuse me of lying (which I don't get why I would lie about something like this) but over the years of LOTS of batches of ALL SIZES and BOTH carboys and buckets, better bottles or glass, carboy caps or bungs, new buckets old buckets, s-types and 3 piece, I get about 50% airlock failure rate (but 100% success rate of fermentation) and it's any number if things, usually simply a non tight seal in the bucket or carboy or grommet....but to me the reason doesn't matter....the point is just trying to glance at an airlock and know what the beer is doing, just is NOT accurate.

My belief is that 1 occurrance is an anamoly, 2 may be a coincidence, BUT 3 or more occurance is an epidemic...and that's the case for folks relying on airlocks all the time, to me if 1 brewer comes on saying his airlock is not bubbling, AND he takes a reading and finds fermentation is going fine, that's an anamoly...

But DAILY on here there are at least 10 threads stating the exact thing...so MAYBE there is something to this idea that airlocks can be faulty. AND if they have the potential to be faulty, then how can we trust them to tell us what's going on?

You can quibble about it all you want, or deal in semantics, but we deal in sheer volume of users on here, and daily we have airlocks not bubbling, and many of them where a gravity reading indicates that fermentation is happening beautifully.

And yes, in an IDEAL situation (like let's say fermenting in a keg with a tight seal and no leak from around the airlock) the airlock SHOULD bubble 100% of the time (providing there's not too much headspace.) If more co2 is created than can be contained in the spavce of the fermenter, THEN an airlock should bubble....because an airlock is a valve.

But MOST of us don't have IDEAL situations, and rarely is a plastic or glass fermenter airtight- it really isn't supposed to be anyway...SO we aren't in the best situation to have IDEAL 100% accuracy of an airlock...


So that's why it's a good idea NOT to relie on or stress out about what it is or isn't doing. Just realize that airlocks bubble or they don't, they start, they stop, they bubble fast, they bubble slow, and they bubble or don't whether fermentation happens or not.

Like I said, the only accurate thing that will tell you what your beer is or isn't doing, is taking gravity readings.

So tell me again how this is an important brewing device?

g-star said:

It's moronic to say that the device is useless. In the vast majority of cases, it would have at least some value indicating the status of a fermentation.

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The only status a bubbling airlock indicates is that your airlock is bubbling, or not....It doesn't tell you why it is, or why it isn't. I think it's moronic to believe otherwise.

One of my favorite pictures ever!

mccumath said:

One of my favorite pictures ever!

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How come yours isn't animating? Or is it my computer?

Ahhh come on! Im not sure! Thats no fun!

This one works.

Anybody ever tried to put a sightglass in the side of a fermentation bucket wide enough for a hydrometer, and place a cap on the top? Wouldn't work with a carboy, obviously, unless you are brave enough to drill glass. Then you could see in real time what the gravity is without taking a sample, etc.

I see a couple problems with this, like how different the gravity is in the tube compared to the rest of the bucket, but it's still kind of a funny idea.

Thanks! I think my gif file was too big, and it automatically changed to a jpg file... will work on that, wont be the last time I get to use this I'm sure... Oh and by the way, my airlock is bubbling away... If only there was a way to monitor the bubbling digitally... haha j/k!

EDIT: Wow just actually clicked on the link above, and boy do I wish I had that much time on my hands! I barely have enough time to squeeze in a brew session every other weekend or so. Think of what you could brew in the amount of time it took to build that... also the cost... Well, whatever floats your boat (guess I can't say too much, my temp controller is built and I have computer pieces coming so I can build a stir plate...)

Honestly, I think the best thing we all can do is RDWHAHB. If you understand the conditions required to ferment your beer optimally, and you supply those conditions to the yeast, they will do their thing. Usually I don't even LOOK at my fermenter for like 3 weeks, when I usually plan to rack into the keg.

**disclaimer - I usually check the airlock the next day to see if it's bubbling. If it is, I'm good to go. If not, I take a visual inside the fermenter and/or take a gravity reading. If there is no indication of fermentation, then like 3 days later I check again. I've never had a ferment not take off after 3 days, and usually the no bubbles thing is simply a poor seal on my bucket and everything is fine.

PoppinCaps said:

Anybody ever tried to put a sightglass in the side of a fermentation bucket wide enough for a hydrometer, and place a cap on the top? Wouldn't work with a carboy, obviously, unless you are brave enough to drill glass. Then you could see in real time what the gravity is without taking a sample, etc.

I see a couple problems with this, like how different the gravity is in the tube compared to the rest of the bucket, but it's still kind of a funny idea.

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Someone talked about it on here years ago, I can't remember if they ever made a version of it.

You know, you could have a little stopcock valve on what you're talking about, that you could open up, it would flood that tube, and you could just drop your hydro in. You could even make it so you could re-close the valve, and maybe rotate the tube to dump the sample into a glass to taste.

Or you could do it as a sealed unit and just open the valve and let the wort flood in. Maybe some sort of glass and brass steampunk contraption with an integrated hydrometer where the stem of it can rise out of the cap. (Think of the plastic stem of a tiregauge sliding in and out of the bottom of the handle.

Yeah, I think it would be too much trouble to even mess with. It would also probably cut the number of new posts in half here if people could simply look at the fermenter and tell what was happening with the gravity...

All I've got to say is that the bubble counter inventor has never met Revvy. Maybe he also has a machine that measure the pressure in a glass bottle to see when bottle conditioning is done. Or one that automatically opens a new one every day and measures the carbonation....

Exactly what you are saying, but you could also place a valve on the bottom end of said sightglass to drain down and out, instead of rotating. It would have to be easy to dismantle for cleaning purposes. Need to get with Bobby M., see what he can come up with. After lots of reading, sounds to me like he is the sightglass guru

PoppinCaps said:

Yeah, I think it would be too much trouble to even mess with. It would also probably cut the number of new posts in half here if people could simply look at the fermenter and tell what was happening with the gravity...

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Yeah, because the majority of those new posts are "My airlock's not bubbling....."

You know, coopers has come out with a plastic hydrometer for about 10 bucks, I don't think it's readily available here in the states yet, but I bet using some pvc fittings, a plastic stopcock,, couple of rubber gaskets, a plexiglass cylinder, and some other bits and bobs you could make a lightweight enclosed hydrometer "sightglass" that you could mount on the side of your bucket just as easily as you could screw on a bottling bucket spigot.....Might even be able to mount it on one of those holed better bottles as well.

hmmmmm

Then you could point a webcam at it and even monitor it remotely online.

[QUOTE
Then you could point a webcam at it and even monitor it remotely online.[/QUOTE]

yeah, great, then instead of walking to the garage to pop the lid on my ferm freezer 8 times a day just to my beers work a little I can stare 18 hours a day at a miniscule change in gravity reading on my laptop screen. This hobby takes up so much time already.

really, the best idea would be to set up an old smart phone to read miniature qr codes printed on the hydrometer as it passes by a small viewing window, which would then be sent to a computer controlled wall mounted scrolling marquis screen displaying the constant gravity readings. I could put it in my living room above the tv.

:rockin:

runningweird said:

yeah, great, then instead of walking to the garage to pop the lid on my ferm freezer 8 times a day just to my beers work a little I can stare 18 hours a day at a miniscule change in gravity reading on my laptop screen. This hobby takes up so much time already.

really, the best idea would be to set up an old smart phone to read miniature qr codes printed on the hydrometer as it passes by a small viewing window, which would then be sent to a computer controlled wall mounted scrolling marquis screen displaying the constant gravity readings. I could put it in my living room above the tv.

:rockin:

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FTW!!!!!

My wife loves me but not that much.

Sounds like we need to make a prototype... Can someone program this into a Windows "gadget" on the desktop screen so I can monitor it continuously... A little live video and a readout of the actual value? I think there needs to be some sort of laser adapted into this build too...

Revvy said:

But bubbles really mean nothing. And some fermenters never bubble. And even if an airlock stops bubbling it doesn't mean fermentation is finished. So it's really useless.

All that work on programming something that means nothing.

It's cute, but useless in reality.

Now if he invented something that could digitally track gravity changes, THAT would be useful.

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How can you say that? when the bubbles slow, it indicates slowed fermentation and it's time to take a reading. I measure with a stop watch to get a feel for how far along the beer is and it's boring. It'd be nice if you can check digitally how often it's been bubbling. You could easily check to see when peak fermentations occur for more accurate timing when switching to secondary. Does look like a bit of work though...

All in all awesome ingenuity. Good find.

Pyroholic said:

How can you say that? when the bubbles slow, it indicates slowed fermentation and it's time to take a reading. I measure with a stop watch to get a feel for how far along the beer is and it's boring. It'd be nice if you can check digitally how often it's been bubbling. You could easily check to see when peak fermentations occur for more accurate timing when switching to secondary. Does look like a bit of work though...

All in all awesome ingenuity. Good find.

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It's not that everybody is not impressed by the ingenuity of individuals, its the overall impression that many people believe that airlock activity is the "best" indication of fermentation. I won't lie, I watch my airlock like a hawk for the first several days of fermentation.

1: Bubbling in the airlock CAN indicate that my yeast has been pitched into an environment that is suitable, and that CO2 is more than likely being produced (On rare occasion, the bucket lid does not sit exactly right, and if I am not holding my mouth the right way, and I don't see any bubbles in my airlock - CO2 escapes from somewhere, but the internal pressure keeps the bugs out of my beloved beer).

2: I watch it to make sure that it does not fill with krausen and blow the lid off (that was my first batch); now I am more prone to use a blow-off tube.

3. You are right in the fact that it does give a "reasonable" indication that fermentation has slowed, however, it never indicates that fermentation has finished. This can only be determined by several gravity readings.

The simple fact is, some folks tend to think that the airlock tells all about fermentation, when that is simply not the way it goes. As stated numerous times in this post, and the other thousand or so "my airlock is not bubbling..." posts, the only way to determine where you are at in fermentation is to take gravity readings with a hydrometer.

Do I wish I had the tech know-how to build a bubble counter? You bet your a*s I do!

Not a fermentation monitor, but I have built a system that monitors temperature, and it surely could reside in a tiny browser window in the corner of your PC if you wish...

I wonder if there is any kind of sensor for detecting alcohol content in liquids...

Homercidal,

Pics of said temperature monitoring device? I hate this forum, always some sweet DIY project I find myself getting excited about!

Homercidal said:

Not a fermentation monitor, but I have built a system that monitors temperature, and it surely could reside in a tiny browser window in the corner of your PC if you wish...

I wonder if there is any kind of sensor for detecting alcohol content in liquids...

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There are some digital hydrometers but they don't look cheap, and I;m not sure how they work. It would be great if there was simply some sort of probe you culd use like a temp probe.

mccumath said:

Homercidal,

Pics of said temperature monitoring device? I hate this forum, always some sweet DIY project I find myself getting excited about!

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I'll see what I can dig up. There is a thread on here about temperature monitoring on the cheap. They might be in that thread.

A lot of people use an Arduino device to monitor and give the feedback.

I'm using a 1-wire network. You can google and see if you think it's worth the effort. I haven't done anything with it since basically getting it working. Maybe when winter sets in, I'll put it back into my to-do list.

In a nutshell: 1-wire is a thumbstick sized USB device with a telephone jack on the other end. You wire a length of telephone wire to a sensor (They can be a small board, or s single tiny sensor, like I'm using). The software on the computer receives the raw data from the USB adapter and does something with it.

In my case I FTP the files to my webserver, so I can see the current temp, or a chart of the temps for the past day, week, month, or whatever. I'd show a sample, but unfortunately my server's Hard Drive crashed this weekend, so those file are now gone forever.

I originally wanted to do this so I could view and record temperature fluctuations in my fermentations, but I've since gotten fermentation chambers built, so I'm not really as curious as I once was...

I *could* wire several of these sensors to the same USB stick, since it's "network" of sensors. Just spread them out along the sensor wire like christmas tree lights. That's the plan: Have a sensor for the ambient air temp, another for the temp inside the chamber, another for the temp inside the fermenter (sensor is so small it could go inside a thermowell), and maybe a sensor to detect when the compressor is running.)

Is all of this necessary? Absolutely not! :rockin:

Hmm....something is making me want to make the hydrometer sightglass prototype...

Then again...something is making me want to make just about every other DIY project on here just for the heck of it.

Yeah this site is notorious for bringing about thoughts of DIY projects. Even had dreams about my temp controller build before the parts got here. I think im pretty lame...

I believe Austin Home brew sell gravity marbles that drop to the bottom when the gravity goes below a certain point.

mccumath said:

Sounds like we need to make a prototype... Can someone program this into a Windows "gadget" on the desktop screen so I can monitor it continuously... A little live video and a readout of the actual value? I think there needs to be some sort of laser adapted into this build too...

Click to expand...

ACTUALLY.... If you had 2 "sightglasses" and 2 laser range finders you could measure the distance form the top of the tube to the Beer in an empty tube and from the top of the tube to the top of the hydrometer in the second. This would allow you to compute the gravity to a very precise degree. Just have to calibrate for the distance between marks on the hydrometer.

Science (and LAZORZ!!!) for the win!

Actually thinking about this a little more, the tube could be in the fermenter with this setup. as long as the top and bottom are open the tube is only there to keep the hydrometer in a pre-defined area the second tube could be done away with by mounting the LAZORZ at the same height and measuring from that distance to the beer and fermenter side by side. The only major issue i see potentially is krausen mucking up the tubes, hydrometer and the distance measurements.

Okay... So we have bubble counters, hydrometers, sightglasses, and lasers, Windows gadgets, temp monitors. Need another bucket for all the above goodies! What else can we incorporate into the build?

Got it! Sharks! Especially sharks with laserbeams on their foreheads!

Okay just kidding. I like the sightglass/hydrometer theory, i am sure that someone has something like this built. Lasers might be a bit extreme, but i want to see it done for sure!

This may be treating the subject with too much gravity (!) but I wonder about the sight glass idea. Can we assume that the gravity in the sight glass would match the gravity in the larger vessel? Is there a gravity gradient at different parts of the vessel? Maybe the turbulence would eliminate that, but the sight glass would be out of that At a minimum it seems there would be a lag.