New to yeast starters.

The answer depends on if you are willing to buy a stir plate.

 

I have a 2 liter flask and a 5 liter flask. The 2L is usually big enough, but I need the 5L sometimes for multi-step starters for big beers, even with a stirplate.

You don't need a stopper or an airlock for a starter. Sanitizes aluminum foil works fine. Arguably better.

 

I make starters in a 2L or 1G jug with sanitized aluminum foil on the top. I don't have a stir plate, so I just shake it up whenever I think to do so. Seems to be working pretty well so far!

 

I suppose you could. It would be pretty shallow, but as long as you can keep the wort moving, I imagine it would be okay. Maybe someone who has actually done this can jump in.

Yes. But it doesn't necessarily have to be the same flask. And when I do multi-step starters, I cold crash and decant the starter beer in between the steps.

 

Multi-Step starters all have more than one step. The second step doesn't necessarily have to be bigger, though it usually is. It depends on how much yeast you are trying to propagate, the starting yeast count, what equipment you have available, and/or how efficiently (in terms of total DME needed) you want to get there. The steps may or may not be in the same flask, depending on the relative flask and step sizes, and on your preference I suppose.

There's a lot of information available on www.mrmalty.com. There's also a calculator there, but it doesn't directly support stepped starters. YeastCalc is another online calculator. It supports stepped starters and is good if you want to fiddle with the starter sizes and see what that does to the output. BrewCipher (a general purpose brewing spreadsheet) includes a yeast calculator that's integrated with your recipe and automatically recommends starter size(s). It also has parameters that can be tweaked if desired. I know there are others, but I don't have much/any experience with them.

 

1.080 is the approximate upper limit for a 2L flask on a stir plate with one pack of yeast and one step.

You can make bigger beers than that with the same setup by using two packs of yeast in the starter and one step.

Play with the Mr Malty calculator and you can determine what fits your needs.

 

A couple of suggestions: learn how many cells you want to pitch. The calculators referred to above, plus Brewers Friend calc, can help here. Then learn about yeast viability. Those little buggers die at ~21% per month . . . with the date of the packet and a calc you compute your real quantity. With these two numbers you 1)know what you have, 2)know where you're going. Then read the "Articles" section on Mr. Malty where there are two long reads about starters. If you understand this you're on the right path. Search this forum for "yeast starters" and "calculators" . . . lots of discussion on the subject.

Call me a geek, but I found it made more sense to get the 5-size flask set (50 - 1000 ml) plus the 2L flask. Once you start applying viability corrections to your quantities you'll end up doing a lot of 500 - 1000 ml initial starters (usually followed by a 2L starter). With this setup I can usually step a packet up to 400+ billion cells (typical lager pitch rate) with two steps. The tiny flasks (20 -250 ml) are handy for storing/measuring. Not a fan of 5L starters (brewing 5 gal batches) but a 3L flask makes sense. Remember, you typically fill the flask to about 75% capacity.

For the most efficient starters try and use a stir plate, oxygen, and yeast nutrient. Concentrate on sanitation like your beer's life depends on it (it does).

 

There's a poster in this forum doing a long-range viability study, but I haven't seen an update in a while. In general I'm of the thought that viability doesn't drop that quickly.

OP, I bought a 3L starter because I calculated that for decent-sized lagers I could grow enough yeast using two steps to pitch 11g. Anything I'd need more cells with, I decided I'd just buy another packet/vial. The 5L flask just seemed like too much for the stir plate I was going to buy (StirStarter, I can vouch for his guarantee) but a 2L was too small, hence the unusual 3L size I chose. In any case, just think about what you brew and then go to one of the online calculators and see what they say you'll need. I really like YeastCalc. In general I brew to package 10g and do a lot of starters on Monday for weekend brewing, whether that is two steps or two starters of two different strains. I always crash and decant before pitching.

 

If you are going to buy a 5L flask, make sure your stirplate will actually move that much liquid. I have built a couple stirplates (very easy to do), but they max out at 2L, maybe 2.5L

 

What viability loss rate do you use? Yeastcalculator.com uses the 21% rate, do you override this by entering a younger date? Do you have a preferred pitch rate?

 

I have 1 and 5 liter, The five give me excellent service for 5 gallon batch, high gravity and lagers. The size make it easy to roll the starter in the flask without stir plate. On the other hand it need space, for the starter process and for storage.

 

Yeah, I basically just fudge the manufacture date. It's by no means scientific. The fresher the yeast, the "fresher" I put into the calc. If I'm dealing with something past expiration I won't make much of a change.

I believe the guy doing viabilities here was showing 90+ more than 4 weeks out, and that just feels right to me intuitively, provided good storage conditions. So if I've got a fresh vial, or if it's yeast I've harvested myself, I'll discount the degradation a bit. If it's old yeast, I'll be more apt to err on the side of the calculators. I just think the curve is not what the calcs use, being flatter at the start and having a steeper dropoff, but again, totally unscientific.