New stir plate seems a little slow?

[GeorgeH2013]

This is my first stir plate, and I've never seen one in action, so maybe this is normal. The video is the stir plate on full speed. Just seems like it should be creating more of a vortex at max speed? It took me a long time to get it to spin, as well. Like the magnet in the stir plate wasn't strong enough, or something. Can't quite wrap my head around it. Maybe much ado about nothing.

Thoughts?

View attachment Video.MOV

 

[porterpounder]

That's enough movement to get things churned up. That's really all you need. What size/type stir bar are you using?

 

[GeorgeH2013]

It's the Stir Starter brand. These are the specs:
A StirStarter stir plate
12 VDC stir motor
Low voltage, plug-in wall transformer
Measures 6 x 4 x 2 inches
Accommodates up to 2000 ml flasks
Teflon coated 1" x 5/16" stir bar included
"Keeper" magnet also included to keep your stir bar on lock when you pitch

I agree it's enough movement. I just thought there would be a little more action.

 

[brew703]

That's the same one I got. I cant view the video while at work but from experience these stir plates don't make big vortex's, especially once the yeast cells begin to grow.

When you first put the flask on the stirplate, set your speed to medium or half. Keep it at that speed until it finishes. I did that last time and it started off with a good vortex then when the yeast began to build there was no vortex but if you look closely you could see everything being churned up. once everything settled, the vortex began again.

I did ask Dan at StirStarter about this and he recommended running on half speed and that did seem to work.

When I first got it, I too thought it was not powerful enough but I was proven wrong. I was also going to get a larger stir bar but he recommended not to.

It would be nice though to have a larger motor so that it can spin better but I guess it's really not necessary.

 

[flars]

I have the same one. It works for well for starters when you start with a small volume of yeast. The stir bar will just stop when using larger volumes of yeast from a saved slurry. It works as advertised.

 

[GeorgeH2013]

Thanks, brew703. That's good to know. I'll try that next time. It certainly is working. Now, if my fermentation takes off on my English ESB tonight, I can call this new step a success!

 

[GeorgeH2013]

Since I have a few yeast starter people looking at this, I have another quick question. Is it best to leave the starter on the stir plate, "stirring," right up until I am ready to pitch? Or should I take it off and let it settle? I planned on just dumping the whole thing in, and not decanting.

Thanks

 

[Soyben]

I think most people prefer to cold crash and let it settle. Starters aren't exactly made for flavor so you are adding extra volume of questionable flavored wort to you fermenter. Many of my brew days are kind of last minute and I have pitched the whole thing and it will make good beer, but if I have time I decant.

 

[HopHeavy]

+1 on Soyben's comments. I like to exhaust the starter, crash overnight, then decant a little while before I boil to allow it to warm up. But yeah, I have also pitched the whole starter as well.

 

[UndeadFred]

If you research graphs, faster is better-- a bigger vortex is better, but it's like a logarithmic curve. You gain almost all of the advantages just by getting the yeast moving, and then after that it is a diminishing return. I built one out of a huge 12V squirrel cage blower motor (available from Sparkfun electronics) mainly because I'm way too cheap to buy a 5L flask for lagers and use a 2 gallon stainless soup pot instead, needing the extra power. Otherwise, something just to get the yeast out of suspension, O2 into the wort for yeast growth, and CO2 out of suspension is all you are looking for or need for a large difference in starters. Good luck with it. Enjoy.

As for cold crashing and decanting? If you have the time always. Taste the starter beer someday if you want to know why. I'd even say on light colored Lagers it's mandatory.

 

[GeorgeH2013]

Great info, guys. Thanks a bunch.

Is 3 or 4 hours long enough to cold crash, or is it not even worth it? I'll start brewing around 4 today, and probably not pitch until 8, so I have a little bit of time to put it in the frig. And I could certainly decant. I've ready so many varying opinions on all of this, I feel like I just need to pick one source, and follow that, as opposed to getting everything mixed up, and doing it differently every time.

 

[UndeadFred]

No.. it isn't really effective to cold crash in my experience until at minimum 24 hours.. 36 is better... 48 is better still... after that it takes weeks to get better... so I shoot for about 30 hours. It does cause me to start a two step lager starter a week in advance.

This of course, also depends on the flocculation properties of the yeast. You might be able to go 12 hours in a "highly flocculent" yeast...

 

[GeorgeH2013]

gotcha. Thanks, UndeadFred. Maybe next time. Just trying to get organized for brew day was one thing. Now, trying to get organized for the starter is a whole new ball game. Fun, but I feel like I'm falling down the rabbit hole...

 

[GeorgeH2013]

Is this normal? What it looked like when I got home.

View attachment Video.MOV

 

[GeorgeH2013]

Ah. finally found that this is pretty standard for WLP002. Crisis averted.

 

[Morrey]

I have this same stir plate, and usually get a full vortex with a 1L starter. You may want to try a shorter or smaller stir bar which worked for me. I have seen charts proving full vortex activity creates a higher cell count.

I usually pitch directly off the stir plate and don't feel that small of a volume of wort will influence my beer as a 5G BIAB brewer. Otherwise you'll need to cold crash a couple of days to drop the yeast out, decant and bring back to temp. The only time I take this additional step is when I do lagers and the yeast needs to be low 50's (F) anyway.



******UPDATE: I saw your new vid...that is a good stir you got going on!

 

[GeorgeH2013]

Yea, Morrey, it worked fine with the 1L flask it came with. 2L just seemed a little big for it, and I didn't even have it full (about 1600ml). Definitely worked, though. Just not what I expected.

I pitched the whole flask in last night, straight from the stir plate. Gave the fermenter a good shaking to try and oxygenate. Got up this morning, and it had a frothy head on top of the wort, but certainly not a vigorous fermentation. Again, not what I expected. I thought a starter was supposed to get a more immediate fermentation? Isn't that part of the idea?