Why is it that every single time I make a yeast starter, it foams up and overflows. I’m using a 2L flask and from a 1L starter to a 2L starter it overflows. I’ve used fermcap and it still overflows. What’s the point in having a stir plate if every single time it overflows and makes a mess. I really don’t understand what I’m doing wrong here.
Yeast starters overflow every single time
- Thread starter Dhagey90
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If you have a Pyrex brand 2L flask, it does not really hold 2L. It will have the highest mark at 1800ml.
If you have a "student grade" knock off flask (from your lhbs, morebeer, northern brewer, etc) then it should have the 2L mark plus headspace.
I have a pyrex i got from the amazon. It overflows every time i do a full 2L starter.
What the hell. I thought I was doing the right thing by buying the more expensive Pyrex brand one. Max marked at 1.8L. I guess I’ll have to buy a 5L flask. However, I feel like these starters will bubble and foam until eternity and the flask size won’t make a difference....
CodeSection
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As pointed out, you will not have that problem with a flask from MoreBeer. I bought their 5L flask Erlenmeyer Flask - 5000 mL | MoreBeer.
While you are researching for a possible replacement flask, you may want to research about silicone in Fermcap and FDA's warning as compared with Patco 376 defoamer. Here is a link to help you get started Where to Buy Birko Corporation's Patco 376 100% Oil Based Defoamer
Ha! Me, too! I have a pyrex 2L, too.
If you have a local home brew shop, it may be best to buy this 5L flask in person as the bottom can be wonky, which makes the stir plate hard to work sometimes.
I got tired of loosing yeast out of my 2L flask and found a 4L on Am-----n for a lot less than the 5L. Plenty big for my needs as I usually over build starters to keep up my yeast bank . I make a 2.5 to 3L starter and bank the extra in half pint mason jars. I can also do starters big enough for Lagers with a 4 L. I almost never use my 2L flask anymore because if the loss of yeast.
I've used regular Fermcap and Fermcap S with great success. I never come close to boil overs in my flasks anymore. I've done up to a 4.5L starter in a 5L flask.
The biggest factor is turning down the flame when it's just ABOUT to boil. Try this: When starting, you can keep the flame on high, as long as you've mixed the dme completely, otherwise you risk scorching the DME. Watch closely when it's almost to a boil. Once you start to see bubbles, turn the flame down to medium low or even low. If you use 3-5 drops of Fermcap, you will not get a boil over. The boil over will open happen if you keep the flame on high.
The biggest factor is turning down the flame when it's just ABOUT to boil. Try this: When starting, you can keep the flame on high, as long as you've mixed the dme completely, otherwise you risk scorching the DME. Watch closely when it's almost to a boil. Once you start to see bubbles, turn the flame down to medium low or even low. If you use 3-5 drops of Fermcap, you will not get a boil over. The boil over will open happen if you keep the flame on high.
Good points.
I dont want to speak for the OP, but i assumed he meant during the 24-48 hours of growth, during Krausen.
My pyrex 2L flask will always over flow during krasuen even with fermcap. And with a hefe strain it is insane
Edit- if i use a full 2L. I can do a 1.5L starter and it is usually ok. Note- hefe's are their own wild beast tho. Use at your own risk!!
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Gotcha. Well, coincidentally, I made a starter this Wednesday and didn't use Fermcap, because I decided not to boil the DME (I heated up to boil, then let cool). 1318 almost jumped right out. Every time I've used Fermcap it's been fine. YMMV, I guess. Maybe I've just been lucky?
Is that a Pyrex brand 2Lor a morebeer like student grade 2L?
Pyrex brand has 1800ml as highest mark, then headspace gets to 2L.
Student grade is 2L, then headspace
Says Pyrex. I got it at a local home brew shop. The one in the picture is a 5L. I have a 2L too, which is Pyrex also.
I've learned to put the stirplate in a plastic "dishpan".
I've cleaned up too may messes, sometimes, the fermcap keeps things under control, others not so much.
I've cleaned up too may messes, sometimes, the fermcap keeps things under control, others not so much.
troglodytes
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I rarely have bubble overs in my starters when I'm doing a 1-1.2L starter in a 2L flask.
However, I, with 100% certainty, will have it bubble over if I stop the stir bar and restart it. It happens every time. Its like the pause in stirring allows a restart to expel all of the CO2 in solution once it restarts.
However, I, with 100% certainty, will have it bubble over if I stop the stir bar and restart it. It happens every time. Its like the pause in stirring allows a restart to expel all of the CO2 in solution once it restarts.
It’s always within the first 5 hours or so that it just freakin foams like hell. I don’t have a problem with it while boiling the wort. It’s when it’s on the stir plate that it foams like hell. It foams so much that I don’t see how even a 5L flask will stop it, but I’m gonna try a 1 gallon glass growler first.
troglodytes
Well-Known Member
Is it possible you have the stir bar spinning too fast and its knocking all the CO2 out of suspension. I try to start my stir bar at a speed just high enough to get a visible whirlpool going, and then back off just a little.
Is anyone decanting after overflow? What about the yeast stuck to tge walls of the flask and rim?
maybe dont use a stir plate. I am in the game with 2 liter and making 1 liter starters. use the shaken and not stirred method. On time after degassing the bubbles reached the top. otherwise not even close.
That's insane. I've made 100s of starters and only had a few blowout. Maybe try 5 drops fermcap during boil? I usually only boil for 10 min or so. I've switched to Propper Starter cans from Omega, and starters have gotten much easier.
Not that it has anything to do with rampaging starters but there really is no need to boil a starter - certainly not longer than a second or so - as pasteurization is actually accomplished in a matter of seconds once the wort temperature rises above 160°F. For this reason I don't actually boil starter wort at all. I bring the prescribed volume of water to a boil in a pot, place the pot in the kitchen sink, stir in three drops of Fermcap, add the DME and stir 'til dissolved, then block the sink drain and add cold water to chill the starter wort to pitching temperature at which point I pour the starter wort into a Star San sanitized e-flask then add the wort...
Cheers!
Cheers!
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