Beer Forum

I have been looking for ways to create large yeast starters (5L or greater) to support lager brewing of 12 gallon batches. I have been trying to propagate smaller starters using a 5 liter flask but my stir plate is having a hard time creating a suitable vortex to promote oxygen from mixing in with the starter.

Looking at the websites that sell magnetic stirrers, for volumes larger than 5 liters, it seems vertical mixers are the preferred method of mixing. These vertical mixers look just like the drill press I have in my shop and I was thinking about rigging my delta floor model drill press with some sort of mixer/drill bit to turn it into a large vertical mixer. Anyone ever give this a try? What were your results? It seems it should be great for making even a 5 gallon starter just as long as I can figure out how to build/buy a mixing rod that will fit into a carboy.

Anyone have any more ideas on whether this will work?

With a stainless steel mix-stir?

http://www.northernbrewer.com/wine-equipment.html

That looks like the ticket. I will post some pics of my test run once I get the stirrers from NB.

While I see this an an interesting idea that just may work, I have some reservations about using a drill press. I assume that you have actually been using the press for the tasks for which it was designed. My concern would be with how well you can actually clean out the accumulated filings sawdust, body parts, etc. from the housing so there is no chance of such stuff falling into the starter.

You might be better off in the long run using an electric ice cream maker motor to drive the mix stir. Those things are specifically designed to run slow for long periods of time around food. This will also allow you to use the drill press to play with your wood while waiting for the starter to finish.

Wayne

Bugeater wrote:This will also allow you to use the drill press to play with your wood while waiting for the starter to finish.

Ha-ha... He said "drill press".


Mylo

I'm getting my ebay shaker soon. This could be the ticket, and you don't have to fool around with a stir bar.

http://cgi.ebay.com/ws/eBayISAPI.dll?Vi ... 0317604417

I'll tell you how it works!

5L should allow you to create an adequate starter for a low gravity lager no problem. I do 12 gallons of German pilsner quite frequently and start things out with a 4L starter of WLP830. If the slurry from the starter looks a little low, I'll toss in an extra vial at pitching time, but I usually don't have to. That's always been my sole method to prop up yeast for subsequent lagers, especially high gravity ones. Don't bother trying to create a starter for 12 gallons of high gravity lager. It's not worth it IMO. Why not brew a low gravity lager and get a full batch of beer out of it? The economics of repitching are hard to beat. If you treat your lager yeast well, pitch "up and across," you should be able to go 5-6 generations without issue. You'll be stoked on how strong your repitches ferment.

If you ran a drill press that long it would probably take a lot of power.