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General Category => Equipment and Software => Topic started by: Pawtucket Patriot on January 11, 2011, 04:29:37 PM

Title: Just ordered a stir plate
Post by: Pawtucket Patriot on January 11, 2011, 04:29:37 PM
Since I'm getting more into brewing lagers, I decided to invest in a stir plate. I ordered one from stirplates.com. It will be nice to just "set it and forget it" instead of doing intermittent shaking.
Title: Re: Just ordered a stir plate
Post by: theDarkSide on January 11, 2011, 04:42:23 PM
A couple hints.

Remember to add the stir bar when boiling your starter and remember to use your magnet on the stir bar before dumping into your wort.

Title: Re: Just ordered a stir plate
Post by: Pawtucket Patriot on January 11, 2011, 04:51:46 PM
Duly noted -- thanks!
Title: Re: Just ordered a stir plate
Post by: bearcat on January 11, 2011, 06:51:56 PM
Awesome gadget to have.  I would also hint to use some anti foam or big enough flask/container to contain the krausen that may happen.   Way to just dramatically increase your yeast count from standard starter methods.



Title: Re: Just ordered a stir plate
Post by: Pawtucket Patriot on January 11, 2011, 07:51:29 PM
Bearcat, is "anti-foam" a homebrewing product?
Title: Re: Just ordered a stir plate
Post by: denny on January 11, 2011, 07:55:32 PM
Yep, commonly sold under the name Fermcap.  As in http://www.northernbrewer.com/default/fermcap-s-1-oz.html .
Title: Re: Just ordered a stir plate
Post by: bearcat on January 11, 2011, 08:05:46 PM
Bearcat, is "anti-foam" a homebrewing product?

Thanks Denny.   The stuff looks like, to me, white slimmy runny glue.   Works really well though and in your BK too.
Title: Re: Just ordered a stir plate
Post by: tubercle on January 11, 2011, 08:16:09 PM
A stir plate is a great investment.

 Then Tubercle got his by thinking quick.

 The boss got me to help him one day to clean out a storage area at work and we were throwing a bunch of stuff away. He picked up a stir plate and said "what is this"?

 The Tubercle said "Not sure ::), but it looks dangerous. I better take it out of here right away and dispose of it". He handed it to me and said "Yea, I guess you're right".  :o

 Straight to the parking lot..... :D :D :D :D

Idiot.
Title: Re: Just ordered a stir plate
Post by: tom on January 11, 2011, 09:22:30 PM
and use a flask at least twice the volume of your starter.
Title: Re: Just ordered a stir plate
Post by: maxieboy on January 11, 2011, 10:42:47 PM
A stir plate is a great investment.

 Then Tubercle got his by thinking quick.

 The boss got me to help him one day to clean out a storage area at work and we were throwing a bunch of stuff away. He picked up a stir plate and said "what is this"?

 The Tubercle said "Not sure ::), but it looks dangerous. I better take it out of here right away and dispose of it". He handed it to me and said "Yea, I guess you're right".  :o

 Straight to the parking lot..... :D :D :D :D

Idiot.

You.....or the boss?  ;D  :D  ;)  :-*

Oh, just got my first stirplate also...
Title: Re: Just ordered a stir plate
Post by: tubercle on January 11, 2011, 11:03:22 PM
A stir plate is a great investment.

 Then Tubercle got his by thinking quick.

 The boss got me to help him one day to clean out a storage area at work and we were throwing a bunch of stuff away. He picked up a stir plate and said "what is this"?

 The Tubercle said "Not sure ::), but it looks dangerous. I better take it out of here right away and dispose of it". He handed it to me and said "Yea, I guess you're right".  :o

 Straight to the parking lot..... :D :D :D :D

Idiot.

You.....or the boss?  ;D  :D  ;)  :-*

Oh, just got my first stirplate also...


 Tubercle's motto: If it's free; It's for me!! ;D ;D ;D ;D
Title: Re: Just ordered a stir plate
Post by: maxieboy on January 11, 2011, 11:16:11 PM
+1  8)
Title: Re: Just ordered a stir plate
Post by: Thirsty_Monk on January 12, 2011, 02:48:59 AM
A couple hints.

Remember to add the stir bar when boiling your starter and remember to use your magnet on the stir bar before dumping into your wort.



I would recommend inserting stir bar into the cold wort before you start boiling.
Title: Re: Just ordered a stir plate
Post by: tygo on January 12, 2011, 03:01:48 AM
I ordered one from stirplates.com.

Let us know how it works.  A stir plate is on my wish list and that seems like a good deal if it works as advertised.
Title: Re: Just ordered a stir plate
Post by: bearcat on January 12, 2011, 03:59:09 PM
I ordered one from stirplates.com.

Let us know how it works.  A stir plate is on my wish list and that seems like a good deal if it works as advertised.

Not to say anything anti- stiplates.com-certainly is easier way to go about obtaining one,,, but you can do this yourself if you have the want-to.  It is the DIY section.  I am have made a few.  It is fun to watch two stir plates going that you made from computer parts and a trip to radio shack.   
Title: Re: Just ordered a stir plate
Post by: Pawtucket Patriot on January 14, 2011, 05:36:19 PM
I looked at diy stirplate guides. Definitely not my kind of project!   :-[ I gladly ponied up the $50 for one from stirplates.com.
Title: Re: Just ordered a stir plate
Post by: Kaiser on January 14, 2011, 06:13:21 PM
Remember to add the stir bar when boiling your

It is very important that you DO NOT add the stir bar after the wort has been heated to boiling temperatures. Because the flask is so smooth the wort is actually superheating if the stir bar is not in there to provide nucleation sites. When you then add the stir bar later the wort will suddenly boil and shoot out of the flask.  This happened to me once and I am lucky that neither I, or someone else got hurt. The wort sprayed 5 ft out of the flask and hit the cabinets.

Kai
Title: Re: Just ordered a stir plate
Post by: theDarkSide on January 14, 2011, 06:17:55 PM
It is very important that you DO NOT add the stir bar after the wort has been heated to boiling temperatures. Because the flask is so smooth the wort is actually superheating if the stir bar is not in there to provide nucleation sites. When you then add the stir bar later the wort will suddenly boil and shoot out of the flask.  This happened to me once and I am lucky that neither I, or someone else got hurt. The wort sprayed 5 ft out of the flask and hit the cabinets.

Kai


Holy smokes!!!  Good tip, thanks!

I really should have stated to add your stir bar before starting your boil.  I usually do this but once I forgot, but I did get it in there before it was on the burner too long.

Thanks for discovering these little things for us.  ;)
Title: Re: Just ordered a stir plate
Post by: Tim McManus on January 14, 2011, 06:24:31 PM
I've never added the bar to the boiling wort and haven't had any issues.

I will boil the wort and DME in a pan while the flask and stir bar are on the plate stirring some iodophor.  I'll dump the iodophor into the ice bath and pour the boiling wort into the flask (which is in the ice bath) with the bar at the bottom.  I haven't had any adverse results (yet).
Title: Re: Just ordered a stir plate
Post by: tumarkin on January 14, 2011, 07:02:35 PM
I've never added the bar to the boiling wort and haven't had any issues.

I will boil the wort and DME in a pan while the flask and stir bar are on the plate stirring some iodophor.  I'll dump the iodophor into the ice bath and pour the boiling wort into the flask (which is in the ice bath) with the bar at the bottom.  I haven't had any adverse results (yet).

sounds like that process is working ok for you, but even with a borosilicate flask you're risking thermal shock & possible cracking by pouring boiling wort into a flask being cooled in ice bath. that process could work right up until it doesn't.
Title: Re: Just ordered a stir plate
Post by: Tim McManus on January 14, 2011, 08:23:09 PM
I've never added the bar to the boiling wort and haven't had any issues.

I will boil the wort and DME in a pan while the flask and stir bar are on the plate stirring some iodophor.  I'll dump the iodophor into the ice bath and pour the boiling wort into the flask (which is in the ice bath) with the bar at the bottom.  I haven't had any adverse results (yet).

sounds like that process is working ok for you, but even with a borosilicate flask you're risking thermal shock & possible cracking by pouring boiling wort into a flask being cooled in ice bath. that process could work right up until it doesn't.

You should see me cringe every time I pour wort in....   ;D
Title: Re: Just ordered a stir plate
Post by: Thirsty_Monk on January 16, 2011, 08:48:21 PM
Remember to add the stir bar when boiling your

It is very important that you DO NOT add the stir bar after the wort has been heated to boiling temperatures. Because the flask is so smooth the wort is actually superheating if the stir bar is not in there to provide nucleation sites. When you then add the stir bar later the wort will suddenly boil and shoot out of the flask.  This happened to me once and I am lucky that neither I, or someone else got hurt. The wort sprayed 5 ft out of the flask and hit the cabinets.

Kai


That is exactly what happened to me.
I was lucky I was wearing paints (No Paints brewing reference).
Boiling wort was all over stove and me.
It shot out about 1 qt of wort from 4 liters.
I was so shocked that I did not know what to do first.
The casualty if this was that sticky wort got into electronics of the stove and we had to replaced it.
I was not hurt.
Live and learn.

So do not do it.
Title: Re: Just ordered a stir plate
Post by: narcout on January 16, 2011, 09:20:11 PM
I always add the stir bar after I've chilled the wort.

NB recently started carring a pretty nice looking stir plate for $66: http://www.northernbrewer.com/brewing/northern-brewer-stir-plate.html
Title: Re: Just ordered a stir plate
Post by: beersk on January 17, 2011, 07:11:08 PM
I always add the stir bar after I've chilled the wort.

NB recently started carring a pretty nice looking stir plate for $66: http://www.northernbrewer.com/brewing/northern-brewer-stir-plate.html

Except that it's out of stock. Boo!
Title: Re: Just ordered a stir plate
Post by: bearcat on January 18, 2011, 02:27:02 PM
There is another procedure that could be followed.   Based on the Maltose Falcons website that utilizes pressure canned wort with no worries of boil overs, cracking your flask due to heat scenario's, etc.
.   
My procedure to make a starter lately has been:

1. sanitize the flask and stir bar.
2. flame the opening of the flask
3. flame lids on a jar or two (depending on starter size) of canned wort and dump into the santized flask
4. add yeast from sanitized yeast vessel.
5. start stir plate.

takes about 5 minutes total.
 
http://www.maltosefalcons.com/tech/starter-made-easy-pressure-cooking-your-starter-wort-ahead-time

Of course there is options of doing the same thing with extra wort from brew day--.

Title: Re: Just ordered a stir plate
Post by: Hokerer on January 18, 2011, 03:57:11 PM
There is another procedure that could be followed.   Based on the Maltose Falcons website that utilizes pressure canned wort with no worries of boil overs, cracking your flask due to heat scenario's, etc.

That's the method I use.  Each time I brew, I take the extra wort (trub pile and such) and drip it through a coffee filter into mason jars and then pressure can them.  Just last night, pressure canned 3 quart jars, 1 pint jar, 2 quarter-pints, and 24 slants.  I'm set for a while.
Title: Re: Just ordered a stir plate
Post by: Pawtucket Patriot on January 27, 2011, 12:31:27 PM
Follow-up question: should I aerate my starter prior to putting it on the stirplate?  I used the starter for the first time last night and just put my flask on the plate after pitching (no prior aeration).  Today, there's a very small foam ring around the top of the swirling starter beer.  I'm not sure what to look for as far as signs of fermentation when using the stirplate.
Title: Re: Just ordered a stir plate
Post by: Kaiser on January 27, 2011, 01:19:19 PM
The starter on the stir plate will aerate itself. Especially if you have a nice wortex that pulls in air

kai
Title: Re: Just ordered a stir plate
Post by: Pawtucket Patriot on January 27, 2011, 03:35:02 PM
The starter on the stir plate will aerate itself. Especially if you have a nice wortex that pulls in air

kai

Ok, thanks. I have the plate stirring such that the vortex is more than a dimple, but not huge. Is it normal to not see much krausen when using a stirplate?  I added two vials of wlp820 to 2L of starter wort last night. Like I said, there is a very thin ring of bubbles around the edges of the swirling starter beer, but that's it.
Title: Re: Just ordered a stir plate
Post by: Hokerer on January 27, 2011, 03:42:18 PM
That thin ring of bubbles around the edge is about all you're ever going to see with the stirplate so you're good.  If you want to have some fun, try and figure out when max growth is going on and then turn off the stirplate - you'll see some krausen then, likely all out the top of the flask and all over the place :)
Title: Re: Just ordered a stir plate
Post by: maxieboy on January 27, 2011, 05:06:58 PM
I'd rather step up starters from one vial. Saves cash. Check this out(from BN forum):


"You can tweak the calculator at Mr Malty to help you work out starter stepping up.

Say you want are brewing a 1.072 bock and you want 500billion cells. Thats either a 6L starter on a stirplate, or 5 fresh packs of yeast. But you can step up instead. You are going to pitch a fresh tube/smackpack into 1.0L of wort as your first step.

So what you do, is juggle the gravity and volume numbers in the calculator, till it tells you that you need a 1.01L starter - dont worry about what you are actually brewing, just muck about till it tells you what you need is 1.01L. Now look at the amount of cells it says that will be in that 1.01L starter. Remember that number. (its about 237billion cells)

OK, without changing anything else - go to the % viability input box and increase it. It will go up past 100%. Increase it till the line that says "vials or packs needed without starter" decreases to 1. It will be roughly the amount of cells you have divided by 100billion. so for our example, the percentage figure where the packs needed figure changes from 1.1 to 1.0 is 226% and it says no starter required.

so effectively you have one smackpack with 226% viability.

Go back to the start - plug in the gravity and volume of the beer you want to make - and set the viability to the percentage figure you just worked out (226%) - and now the calculator will tell you what size to make your "second" starter if you use the yeast from the first one. in this example it tells us we need a 2L starter to go from our 237billion cells to 500billion.

So you start with a fresh vial - make a 1L starter - then either decant the beer and add 2L of fresh wort to the yeast, OR assume that all the nutrient is gone, and add a further 1L of double strength wort (which when diluted with the first one = 2L of starter strength wort) - and this will give you the approximately 500billion cells you need. And your starter was never more than 2L.

Ive gone 1L - 2L - 4L and ended up with over 1000billion cells for a big batch of strong beer."

edit: quotes and link
Thread here (http://www.thebrewingnetwork.com/forum/viewtopic.php?f=19&t=12581&start=10#_thread)



Title: Re: Just ordered a stir plate
Post by: Kaiser on January 27, 2011, 05:48:11 PM
Ive gone 1L - 2L - 4L and ended up with over 1000billion cells for a big batch of strong beer

Maxieboy,

How did you check that you had about 1,000 B cells?

I'd be careful in using Jamil's calculator in a way that it may not have been designed for. Mostly because Jamil's experiments may have made certain assumptions.

I have been looking into yeast growth as well and some of the things that Jamil was/is seeing don't line up with what I'm seeing. For example I don't see much difference in new yeast growth per extract for different initial cell concentrations. At least up to a point.

What I'm seeing is that on a stir plate you get about 1.1 - 1.4 B new cells for every gram of extract in your wort. What this means is that your 6 l of 1.040 wort can grow 660 - 840 B new cells. To what extent that can be optimized by stepping up, I.e. splitting the 6l into steps, I don't know. I suspect that if you need to let fermentation finish in each of these steps to decant the starter wort you may loose some efficiency since more of the available energy needs to be spent to maintain the yeast during those dormant phases.

Kai
Title: Re: Just ordered a stir plate
Post by: richardt on January 27, 2011, 06:58:49 PM
Practically speaking, I'd rather have a yeast pitching calculator that tells me to pitch one vial or smack pack of yeast into 1 liter of "x" SG wort, aerate on a stir plate or with aquarium pump/tubing for "y" days, to get "z" cells/ml. 

Based on the calculated or planned OG of my beer, it would then advise me whether or not I needed to do further step ups for the starter and provide details how to do such with regards to starter wort volume, starter wort gravity, starter size, number of steps, etc.  Very few of us have a hemocytometer. 

The counts aren't practical, in my view, but telling me that I should have an adequate number of cells in a 600 ml yeast cake in my cold-crashed 2 liter yeast starter after pitching a smack pack into 1.040 starter wort and giving it 72 hours to grow and 48 hours to chill would be more useful info for me.
Title: Re: Just ordered a stir plate
Post by: Kaiser on January 27, 2011, 07:07:00 PM
Practically speaking, I'd rather have a yeast pitching calculator that tells me to pitch one vial or smack pack of yeast into 1 liter of "x" SG wort, aerate on a stir plate or with aquarium pump/tubing for "y" days, to get "z" cells/ml.

Yes, that’s what I was thinking as well. It always bothered me that Jamil would assume that I’d be starting with more than 1 vial/pack of yeast. And from my experience, if you start with that many cells (50-100B) you can pitch directly into the final starter volume if you have a large enough starter vessel.

Quote
Very few of us have a hemocytometer. 

Most of us have scales and I do think that we can weigh the sediment and use that to estimate the actual cell count. Especially in starters where you tend to have less trub.

Kai
Title: Re: Just ordered a stir plate
Post by: maxieboy on January 27, 2011, 09:04:27 PM
Ive gone 1L - 2L - 4L and ended up with over 1000billion cells for a big batch of strong beer

Maxieboy,

How did you check that you had about 1,000 B cells?

I'd be careful in using Jamil's calculator in a way that it may not have been designed for. Mostly because Jamil's experiments may have made certain assumptions.

I have been looking into yeast growth as well and some of the things that Jamil was/is seeing don't line up with what I'm seeing. For example I don't see much difference in new yeast growth per extract for different initial cell concentrations. At least up to a point.

What I'm seeing is that on a stir plate you get about 1.1 - 1.4 B new cells for every gram of extract in your wort. What this means is that your 6 l of 1.040 wort can grow 660 - 840 B new cells. To what extent that can be optimized by stepping up, I.e. splitting the 6l into steps, I don't know. I suspect that if you need to let fermentation finish in each of these steps to decant the starter wort you may loose some efficiency since more of the available energy needs to be spent to maintain the yeast during those dormant phases.

Kai

 I should have put quotes around the whole thing. The one thousand billion cells statement is the BN poster's. JZ did weigh in later in the thread and thought that the process was sound.

I am FAR from an expert on this subject. I just got into stirplate starters and was looking for info on starters and stepping them up in order to save a little money while assuring proper pitch rates as well. I'll probably never get in to counting yeast cells and I think this method gets me as close as I need to be. I am always looking to simplify and streamline my process and this fits the bill for me.

The calculator does allow you to build your starter from one pack to your starter in one step but in most cases you're going to need a vessel larger than 2L(for 10g batches). The advantage in the process above is that you can do a 2 step starter in the one 2L vessel(stirplated) and get aprrox.450- 500B cells which is what I need for the majority of my 10g batches.

Wow, is it hard to type and edit a response when everything doesn't fit into the space allotted or what?! Yecch.
Title: Re: Just ordered a stir plate
Post by: Hokerer on January 27, 2011, 09:34:59 PM
Wow, is it hard to type and edit a response when everything doesn't fit into the space allotted or what?! Yecch.

Yayyyy!!!  It's not just me.  When I'm typing a post and go beyond the limits of the text entry box, things go absolutely nuts.
Title: Re: Just ordered a stir plate
Post by: Pawtucket Patriot on January 28, 2011, 02:19:23 AM
Update: I got home from work and took a look at my stirring starter.  There's definitely more activity evident at this point.  It's been fermenting for about 24 hours.  I turned up the speed a bit and there is more foam forming at the surface.  Looks like I'm growing yeast!