5 Gallon Stir Plate

[thargrav]

For those of you receiving sample stir plates, they will ship tonight. The motors finally came in today.

Also, these will ship with a single 2" stir bar & not 2 like the production stir plates will, but they are samples.

One thing you will notice right away with 5 gallons is you will not be able to turn the speed up past 1/4. But even at 1/4 you will get a larger vortex than you would in a 2 liter starter with another stir plate and all of your yeast will stay in suspension (already verified by me). The reason is - a motor that provides enough torque to spin 5 gallons also provides more than enough torque to pull away from the stir bar at higher speeds.

Thanks again for volunteering to test these and providing feedback. You are welcome to post the results to this board or directly to me.

Tom

 

[thargrav]

The stir plates that are going out are shipping to:
Joey
Doug
Chris
Mathew

I'm missing someone. If I promised you a stir plate and your first name was not on this list please PM me!

 

[Bugaboo]

Looks awesome man! I can see the appeal. You could probably wash your clothes with a stirplate that big

 

[emjay]

Looks awesome man! I can see the appeal. You could probably wash your clothes with a stirplate that big

It would create too much resistance for the stir-bar to push through, but that's a very funny thought

If anybody stresses out about making sure their priming sugar is evenly dispersed though, I really can't think of a better way!

 

[mavrick1903]

Thanks Tom. Can't wait.

 

[Dirty]

Cant wait. Got plans for a 120min IPA clone, Imperial Stout, and possbly a Quad on steroids.

Rock Chalk

Chris

 

[emjay]

As long as the airlock has a good seal, all of the oxygen in the head-space has either been absorbed at the beginning of fermentation (when oxygenation is a good thing), or has been displaced by CO2 created by active fermentation. The atmosphere in the carboy is inert with CO2.

Hopefully that's the case, and theoretically it seems fine, but I've been doing this long enough to know that the science is often more complicated in reality (eg things get unaccounted for), but the positive pressure should keep oxygen out. There might be a small chance that movement of air caused by the stirring could push out enough air that pressure equilibrium causes a bit of (oxygenated) air to also seep in, but if that's even possibly, it would pretty much have to be through a leak - usually where the bung makes a seal against the neck of the carboy, where the lid makes a seal again the rim of the bucket, where the grommet makes a seal against the lid, or even where the airlock makes a seal against the grommet or bung. But these kind of leaks generally cause the fermentor not to bubble even at the peak activity (although sometimes it just greatly reduces their size and frequency), so with this baby, there might be an actual good reason to be concerned with airlock activity!

Of course, the possibility of that even happening is mere speculation, and even I'm doubtful about it. But it raises another issue that hasn't even been mentioned yet, despite the fact that it could possibly be the biggest benefit of all to fermenting on a stirplate...

The fact that it drives off CO2. Carbon dioxide is bad for yeast. They don't like it at all. And yet, it's generally unavoidable because they produce copious amounts of it. And to make matters worse, the head pressure created by the water column in the airlock allows it to dissolve in even higher concentrations. But the constant agitation should keep the dissolved CO2 to a minimum, and the benefit to this may be even greater than keeping the yeast in suspension. Even more so if you harvest the yeast and use it for many successive generations, making you especially concerned about yeast health/vitality.

I can't wait to split a 10gal batch into 2 in order to compare them! I should probably decide on a style and start creating a recipe soon... something that doesn't require fermentor additions (eg dryhopping, in order to ensure both batches are identical), and is formulated to highlight and emphasize any anticipated differences, such as using a high-flocc'ing yeast strain that drops out of suspension very quickly when it doesn't have the assistance of a stir-plate.

 

[Bugaboo]

Looks awesome man! I can see the appeal. You could probably wash your clothes with a stirplate that big

ok ok maybe just a couple pairs of socks.

 

[GNBrews]

Hopefully that's the case, and theoretically it seems fine, but I've been doing this long enough to know that the science is often more complicated in reality (eg things get unaccounted for), but the positive pressure should keep oxygen out. There might be a small chance that movement of air caused by the stirring could push out enough air that pressure equilibrium causes a bit of (oxygenated) air to also seep in, but if that's even possibly, it would pretty much have to be through a leak - usually where the bung makes a seal against the neck of the carboy, where the lid makes a seal again the rim of the bucket, where the grommet makes a seal against the lid, or even where the airlock makes a seal against the grommet or bung. But these kind of leaks generally cause the fermentor not to bubble even at the peak activity (although sometimes it just greatly reduces their size and frequency), so with this baby, there might be an actual good reason to be concerned with airlock activity!

Of course, the possibility of that even happening is mere speculation, and even I'm doubtful about it. But it raises another issue that hasn't even been mentioned yet, despite the fact that it could possibly be the biggest benefit of all to fermenting on a stirplate...

The fact that it drives off CO2. Carbon dioxide is bad for yeast. They don't like it at all. And yet, it's generally unavoidable because they produce copious amounts of it. And to make matters worse, the head pressure created by the water column in the airlock allows it to dissolve in even higher concentrations. But the constant agitation should keep the dissolved CO2 to a minimum, and the benefit to this may be even greater than keeping the yeast in suspension. Even more so if you harvest the yeast and use it for many successive generations, making you especially concerned about yeast health/vitality.

I can't wait to split a 10gal batch into 2 in order to compare them! I should probably decide on a style and start creating a recipe soon... something that doesn't require fermentor additions (eg dryhopping, in order to ensure both batches are identical), and is formulated to highlight and emphasize any anticipated differences, such as using a high-flocc'ing yeast strain that drops out of suspension very quickly when it doesn't have the assistance of a stir-plate.

Right. Any pinhole will expose the beer to oxygen. Air is 21% oxygen and atmospheric pressure is 14.7PSI. Since there is no oxygen inside the carboy, atmospheric oxygen is now attempting to diffuse, with .21 X 14.7 = ~3PSI of pressure, on all of the outer surfaces of the sealed container. The airlock is keeping that oxygen out. While it's true that CO2 is heavier than air, if you have a leak, that ~3PSI of oxygen will rush in and become part of the gas mixture inside

While CO2 is technically toxic to yeast, having some in solution actually creates a cleaner tasting beer by inhibiting some yeast metabolism. It will definitely be interesting to hear what stir plate fermentations taste like.

There's a thread over in the "General Techniques" section about pressurized fermentation if you want to read more. Also, here's an article from Applied Microbiology and Biotechnology, titled "Effects of CO2 on the formation of flavour volatiles during fermentation with immobilized brewer’s yeast".

 

[mavrick1903]

Tom, USPS was good to me today. I'll plan on doing a starter this week, for a brew Fri-Sun somewhere in there, that we'll keep spinning.

I do wonder, is the plate big enough (wide enough) to safely support a 5g carboy? or would a little time spend in my wood shop for something be a worthwhile investment. Not a knock on design, just trying to overcome that queasy feeling we all get when we think of a brew-in-carboy breaking.

Thoughts?

also, I suppose with the beer in suspension during fermentation, does one need to rack to secondary? or should the plate be put into play FOR secondary? I'm also guessing that a brew spinning will require nothing more than an airlock and that a blow off tube would be unnecessary.

 

[thargrav]

The stir plate has no problem supporting a 5 gallon carboy. I've had one spinning on one of my prototypes for over a month.

If you are really concerned you can use a non-skid pad like one of these.
http://www.amazon.com/dp/B000P910W8/?tag=skimlinks_replacement-20

Also, you will need to let the brew settle and/or rack to a secondary but since the yeast will be finished it should not take too long for the beer to settle.

The sample stir plates shipped with one stir bar but the production stir plates will ship with two. To remove the stir bar you pull the carboy off the stir plate, find the stir bar with a outside magnet then just walk it up the outside of the carboy with the outside magnet.

 

[Dirty]

Got mine yesterday as well

Looking forward to doing a batch asap.

Anyone doing the testing willing to share the recipe they will be brewing?

Rock Chalk
Chris

 

[GNBrews]

Dirty - The only way the OP is going to get usable data from your testing is if you brew a recipe that *you've* brewed before and understand its nuances and how they've changed for better or worse from the stir plate treatment.

 

[Dirty]

Got it. Misunderstood the original intent. My 10 gallon system should be up an running soon and ill do a couple high gravity split batches to compare side by side.

Rock Chalk

Chris

 

[thargrav]

And BTW, that's what I'm looking for - actual results. I may have designed this beast but I'm only one person. I already know that the stir plate works. But does it do what I intended the design to do? Does it keep high gravity brews working that would have stalled and do high gravity brews finish faster? I know from experience that high gravity brews can drag on for what seems forever.

My next high gravity experiment will be a mead with 15 pounds of honey diluted with enough water to make 5.5 gallons. I hope to have the batch started this weekend. A typical fermentation cycle for one of these meads is 3 months for me. Then I have 6 months of settling time after the fermentation is done. I'm hoping that my new stir plate will reduce fermentation to one month or less.

 

[thepirho]

I would love to have a stir plate that could reduce the fermentation time for a mead like that. You are planning on stirring the mead during fermentation, for the full length, or just first week or 2?

I had a brochet that just didn't want to ferment. Stirring might have helped.

 

[thargrav]

I plan on stirring for the full length.

Just like the ones I gave samples to, I'll post the results to this board.

 

[thargrav]

I just posted a new video of the stir plate. Thanks, joeybeer for all of your help!!!!

 

[joeybeer]

It really is an awesome stir plate, it's incredibly powerful - one of those tools that you know will work the first time and do whatever you want it to. The Ferrari of the stirplate world

 

[user 84304]

I wish I'd have found this early enough to be one of the testers. I mean, I know why you made it and I brew really high gravity on most of my brews. I have an RIS I'm looking to make that's super high gravity(like 1.148) and I know I'd want this. Oh well, maybe I'll buy one when I can pony up the bucks. Sweet plate, though, you should be proud

 

[thargrav]

Thanks, I'm eagerly waiting feedback. I was supposed to start a batch of mead on the one I'm using this weekend but things got too busy around here. Maybe I'll start it tomorrow.

 

[emjay]

Still waiting for mine... hopefully I'll get it soon

 

[thargrav]

Yours was shipped the same day as the others. I marked it as a gift with a very low value since you did not pay anything for the stir plate - maybe Customs is having heartburn over it?

 

[emjay]

Yours was shipped the same day as the others. I marked it as a gift with a very low value since you did not pay anything for the stir plate - maybe Customs is having heartburn over it?

Who knows... nothing to be concerned about yet though.

Although labelling it as a commercial sample would have been the most appropriate thing, it shouldn't matter either way

 

[emjay]

Just received it as I was leaving the house. It actually WAS labeled as a commercial sample. I'll try it out when I get back

 

[mavrick1903]

Well, mine is turnin n burnin. Brewed on Monday. I made two starters prior, both large. one was 2L the other was a half gallon. Honestly, I liked the preformance in the growler better (shape, I'm sure). The Plate is under (no extra supports, and feels fine, just like Tom said) a Dunklewisen, sitting next to a Stout. similar grain bills, and similar OG. We'll see which wins! (both batchs brewed on Monday)

 

[thargrav]

We finally have the Black MAXX Stir Plate page up on the stir-plate.com web site.
http://www.stir-plate.com/BlackMAXX.htm

 

[emjay]

Damn... haven't put anything on it yet, but it seems damn powerful. I first ran it on an uneven surface, and it sounded like a washing machine that's ALSO on an uneven surface!

It's a bit late in the year, but I think I'm going to make 10gal of saison using the notoriously slow Dupont yeast, and ferment half of it on this thing. It'll give me a good chance to see not just if it can speed up the fermentation, but also how it affects production of esters and phenols, which should be very noticeable.

Speaking of which... is this thing waterproof? My current ferm chamber gets a lot of condensation, but I'm also wondering if it can take spills and whatnot.

 

[thargrav]

Damn... haven't put anything on it yet, but it seems damn powerful. I first ran it on an uneven surface, and it sounded like a washing machine that's ALSO on an uneven surface!

It's a bit late in the year, but I think I'm going to make 10gal of saison using the notoriously slow Dupont yeast, and ferment half of it on this thing. It'll give me a good chance to see not just if it can speed up the fermentation, but also how it affects production of esters and phenols, which should be very noticeable.

Speaking of which... is this thing waterproof? My current ferm chamber gets a lot of condensation, but I'm also wondering if it can take spills and whatnot.

You can't submerge it in water but spills aren't a issue. Also, my son runs his in the fridge.

 

[thargrav]

Any additional feedback from the samples I sent out?

Thanks, Tom