5L starter on stir plate aeration question

[cervid]

So, I just made my first 5L starter. I have a foam stopper in it and I'm not really comfortable shaking it up prior to pitching like I usually do.

So, I put it on my stir plate and am letting it run while I warm up this yeast. The vortex is ok, but not huge and swirling like it is in smaller starters. I actually got about 5.5L in this thing..

So.. will this add enough oxygen while my yeast is warming, or should I sanitize a piece of saran wrap or something and try to cover the top and shale it? That just seems risky and one more step, adding risk.

No, I don't have an O2 stone, I always just shake the hell out of my carboy because it's free and I always have more stuff to buy.. I guess maybe I should get an O2 system one day, but I digress.

 

[BrewCrewKevin]

That should be fine. The stir plate is more to keep the yeast in suspension, and as long as it's stirring, it will keep the surface area moving. That's really what gets the oxygen into it.

 

[Misplaced_Canuck]

That should be fine. The stir plate is more to keep the yeast in suspension, and as long as it's stirring, it will keep the surface area moving. That's really what gets the oxygen into it.

And the CO2 out!

MC

 

[BrewCrewKevin]

And the CO2 out!

MC

Correct.

Although any sort of airlock lets CO2 out. Obviously you need to do that so it doesn't explode. For yeast starters, however, it's equally important that you let O2 in. So instead of a standard S-type or 3-piece airlock, it's better to use sanitized tin foil.


OP: I'm not familiar with the foam stoppers. Do they let it breathe, too?

 

[Misplaced_Canuck]

Correct.

Although any sort of airlock lets CO2 out. Obviously you need to do that so it doesn't explode. For yeast starters, however, it's equally important that you let O2 in. So instead of a standard S-type or 3-piece airlock, it's better to use sanitized tin foil.


OP: I'm not familiar with the foam stoppers. Do they let it breathe, too?

Well the point i was trying to make is that the stirring drives out the CO2 much quicker than a non-stirred vessel. It's very obvious in my stir-plate starters.

MC

 

[cervid]

Yeah, i got mine from northern brewer, lab supply sells them too. They are cool. Starter is already raging krausen. Maybe 3 hrs.

 

[Jrock817]

I often make a 4L starter with my 5L erlenmeyer. I put it on a stir plate, and I think it helps, but it is so big, you can't really get a good sharknado going. But all the food for the yeast is enough, with aeration. Take a picture before you go to bed, and when you wake up, you won't believe it

 

[Jrock817]

And buy an 02 stone. It changed my life. Everything is so much faster, bigger starter = faster fermentation! more 02 in primary = faster fermentation = quicker beer drinking. And it looks really really cool

 

[cervid]

I often make a 4L starter with my 5L erlenmeyer. I put it on a stir plate, and I think it helps, but it is so big, you can't really get a good sharknado going. But all the food for the yeast is enough, with aeration. Take a picture before you go to bed, and when you wake up, you won't believe it

When I woke up the krausen was so big it was into the foam stopper! And that was with fermcap. It's San Fran Lager.

The O2 system is about all I don't have and I've never minded shaking stuff, I guess if I were smaller it would matter.

I don't do a lot of high gravity, but I guess for my next one I will.

I goofed up and made the starter bigger than I wanted to, so that was part of it. Next time, I'll make sure I get it at 4L to 4.5L as my biggest.

 

[Cyclman]

+1 on O2 injector, love the impact mine has had.