erlenmeyer flask boilover

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Black Island Brewer

An Ode to Beer
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I just can't seem to boil starter wort in an erlenmeyer without a boil over. Today I even tried boiling on a pot until the hot break dropped, then put it in the flask and returned it to a boil, only to have it boil over. Other than additives, does anyone have and suggestions? What do you do to make your starters?
 
I ended buying a 4l flask for a 2 or 3l starter. Before that, I would gradually ramp the temp up (2l starter in a 2l flask) on the stove and boil at a the lowest temp possible. If I took it easy on the temperature I could get away with it. Like I said though I got tired of babying the 2l flask and just bought a larger one.
 
I recently started using a couple drops of fermcap in order to boil in my 5L Erlenmeyer and I still need to watch it like a hawk.

What I used to do is boil the starter wort in a separate pot while also boiling some water in the assembled (flask, stirbar, foam stopper) Erlenmeyer rig to sanitize. Once done drain the flask and pour in the wort with a large sanitized funnel.
 
I used to place a long skewer in the flask. It seems to give early nucleation sites, and the boil happens a bit early and no boil over. It seems to work, but its probably all in my mind. Fermcap S is fantastic but the op asked for no additives. Personally, I've gone to Fermcap S.
 
Other than slowly increasing heat which will take forever, using a gas stove with more precise control or getting a bigger flask, no additive free suggestions. I use one drop of ferm cap in a 2L of starter and it works great but you still need to watch it. By the time I crash cool and pour off the wort and pitch the slurry it is less than a drop total in 10 gallons which is pretty minimal. I also think I read somewhere that some of it gets boiled off so I really don't think the one drop in a starter something to be concerned about.
 
DWhitwell said:
I just can't seem to boil starter wort in an erlenmeyer without a boil over. Today I even tried boiling on a pot until the hot break dropped, then put it in the flask and returned it to a boil, only to have it boil over. Other than additives, does anyone have and suggestions? What do you do to make your starters?

I had the same problem. Now I boil in a separate pot for 10 minutes. Transfer to a sanitized flask and bing to a gentle boil. It takes little to no heat on the flask if pre boiled.

I mainly just want my flask as a flat bottomed vessel I can use extremely hot liquids in and quick cool down without it shattering. Then onto a stir plate.

Extra pot involved and a few more minutes but this works okay for me
 
Fermcap works awesome. It's good too for when you throw your bar and then have to start spinning again mid ferment.

I don't boil the starter anymore though. I just get it close and call it good.
 
I had the same problem. Now I boil in a separate pot for 10 minutes. Transfer to a sanitized flask and bing to a gentle boil. It takes little to no heat on the flask if pre boiled.

I mainly just want my flask as a flat bottomed vessel I can use extremely hot liquids in and quick cool down without it shattering. Then onto a stir plate.

Extra pot involved and a few more minutes but this works okay for me

Dan, this is what I was attempting, what I didn't do was preheat the flask. It seems to be the best solution without adding non-beer ingredients. I think next time I'll make my starter wort a little higher gravity, and while it's boiling I'll boil the rest of the water in the flask, turn off the heat, add the wort, then get it back up to a gentle boil.

I wonder, though, if returning it to a boil is really necessary. I'm thinking I could sterilize the flasks in the oven, allow to cool with the foil on top, and add the boiled wort to the flask.

I'm also wondering if anyone pressure cans starter wort? It sure would save the time of boiling and cooling separate starters.

Thanks for the help, all! I'm glad it wasn't just me having the problem!
 
I boil in a pot now and chill the wort in the covered pot. I then pour it into the sanitized flash and add the yeast, then start the stirplate. I don't boil at all in my flask anymore. It is so much easier in a pot.
 
I submerge my flask, the foam stopper, & a funnel in star san.
I boil my wort in a small pot, then set it in an ice bath to chill it.
When its at room temp, I pour my wort into the flask, using the funnel.
Then add my yeast & the stopper and I'm good to go.
 
Boiling in a pot can work but when working with yeast you have to be extra cautious with sanitation. The reason for boiling in the flask is you eliminate the chance of infecting a batch while transferring from the pot to the flask and it ensures the flask is totally sanitary as well. If you do choose to boil in a pot inside of the pot I would recommend using a stainless steel pot rather than non-stick so that you can take a lighter to the rim of the pot where you are going to pour it into the flask.

Do you guys who do not use fermcap ever have issues with krausen spilling out the top of the flask? That is another thing it is good for preventing. The one drop I add before boiling solves the boil over issue and reduces krausen.

I really don't understand what the issue with fermcap is. The amount that ends up in the final beer from one drop in your starter is minimal. If you use a no rinse sanitizer small amounts of that end up in your beer. If you use bottles instead of kegs then even more sanitizer ends up in the beer. For the most part my beer is just barley, water, hops and yeast with the exception of minerals because my water is really soft and the one drop of fermcap.

I was curious about how much that one drop really is so I did the math. In my 10 gallon batches that one drop is close to 1 part per million and potentially even less because I crash cool my starters so I can pour off the wort and just pitch the yeast. So in a 5 gallon batch the one drop in the starter would be 2 parts per million or less. The FDA guidelines require it to be less than 10 parts per million which it already is way under. What this doesn't take into account is that yeast will also work to eliminate the fermcap, basically any that is left after fermentation has adhered to the yeast so when you move your beer from the yeast cake, the final product in the bottle or keg with far less yeast in it is going to have way way way less than the one or two parts per million you started with so with the 10ppm guideline and only having a fraction of a ppm in your final beer I think you should be good to go.

If you are really worried about it I think there are also some more natural oil based anti-foam agents.
 
I boil in a pot now and chill the wort in the covered pot. I then pour it into the sanitized flash and add the yeast, then start the stirplate. I don't boil at all in my flask anymore. It is so much easier in a pot.

I'm thinking for chilling the wort, this would be easier. Don't know why I've been so dead set on boiling in the flask. Maybe because everyone says that's what they do. BAAAAH, I say! (as all sheep do...)
 
Boiling in a pot can work but when working with yeast you have to be extra cautious with sanitation. The reason for boiling in the flask is you eliminate the chance of infecting a batch while transferring from the pot to the flask and it ensures the flask is totally sanitary as well. If you do choose to boil in a pot inside of the pot I would recommend using a stainless steel pot rather than non-stick so that you can take a lighter to the rim of the pot where you are going to pour it into the flask..

Good point, so I'm back to thinking that a quick boil in the flask might be easier, although I like the idea of flaming the rim of the pan. And as someone who avoids agents like fermcap (although apparently anyone eating chicken mcnuggets is eating polydimethylsiloxane - i've been off the nuggets for years now) I also don't cook on non-stick pans.

I really don't understand what the issue with fermcap is. The amount that ends up in the final beer from one drop in your starter is minimal. If you use a no rinse sanitizer small amounts of that end up in your beer. If you use bottles instead of kegs then even more sanitizer ends up in the beer. For the most part my beer is just barley, water, hops and yeast with the exception of minerals because my water is really soft and the one drop of fermcap.

I was curious about how much that one drop really is so I did the math. In my 10 gallon batches that one drop is close to 1 part per million and potentially even less because I crash cool my starters so I can pour off the wort and just pitch the yeast. So in a 5 gallon batch the one drop in the starter would be 2 parts per million or less. The FDA guidelines require it to be less than 10 parts per million which it already is way under. What this doesn't take into account is that yeast will also work to eliminate the fermcap, basically any that is left after fermentation has adhered to the yeast so when you move your beer from the yeast cake, the final product in the bottle or keg with far less yeast in it is going to have way way way less than the one or two parts per million you started with so with the 10ppm guideline and only having a fraction of a ppm in your final beer I think you should be good to go.

I respect how you arrive at your decision. I wasn't able to verify that yeast use or absorb polydimethylsiloxane the same way it utilizes the ingredients in starsan, though. As for me, I just try to limit my exposure to additives like fermcap out of general principle. If I can do without it, I'd rather do it that way. :mug:

So, from all of the input (and thanks to all of you for it), I think I'm going to boil the starter in a pot and chill it in the pot, boil a small amount of water in the flask with the foil to sanitize both and let it cool with the foil on, sanitize a funnel, flame the rim of the pot, add the starter to the flask, drop in the yeast and stir bar, and get it on the plate.

Just as a caution for anyone who doesn't already know: don't open your WLP vial immediately after vigorously shaking it. I did. You won't like it.
 
I boil in a pot now and chill the wort in the covered pot. I then pour it into the sanitized flash and add the yeast, then start the stirplate. I don't boil at all in my flask anymore. It is so much easier in a pot.

this. not sure why so many believe it to be necessary to boil in the flask. When we boil things in a flask in the lab we use boil beads. These are glass beads that disperse the heat and keep it from getting out of control. This of course would not work all that well with our application. I have never boiled in the flask at home.
 
Replys:
Boiling in a pot can work but when working with yeast you have to be extra cautious with sanitation. The reason for boiling in the flask is you eliminate the chance of infecting a batch while transferring from the pot to the flask and it ensures the flask is totally sanitary as well. If you do choose to boil in a pot inside of the pot I would recommend using a stainless steel pot rather than non-stick so that you can take a lighter to the rim of the pot where you are going to pour it into the flask.

I have made about 30 starters, Boiled in the flask for only the first couple. I rinse everything in Starsan, never flame anything, make step starters and have had no issues.

Do you guys who do not use fermcap ever have issues with krausen spilling out the top of the flask? That is another thing it is good for preventing. The one drop I add before boiling solves the boil over issue and reduces krausen.

I don't use fermcap in my starters. I use a stirplate and rarely get much more that 1/8 to 1/4 inch of krausen.

I really don't understand what the issue with fermcap is. The amount that ends up in the final beer from one drop in your starter is minimal. If you use a no rinse sanitizer small amounts of that end up in your beer. If you use bottles instead of kegs then even more sanitizer ends up in the beer. For the most part my beer is just barley, water, hops and yeast with the exception of minerals because my water is really soft and the one drop of fermcap.

Starsan is just a very weak acid and water it just changes the chemistry of the water. Fermcap is silicon. I don't really worry about the silicon and use it occasionally. It is recommended that you filter it out of the beer. Though very few do this since it settles to the bottom and stays in the trub that gets discarded.

I was curious about how much that one drop really is so I did the math. In my 10 gallon batches that one drop is close to 1 part per million and potentially even less because I crash cool my starters so I can pour off the wort and just pitch the yeast. So in a 5 gallon batch the one drop in the starter would be 2 parts per million or less. The FDA guidelines require it to be less than 10 parts per million which it already is way under. What this doesn't take into account is that yeast will also work to eliminate the fermcap, basically any that is left after fermentation has adhered to the yeast so when you move your beer from the yeast cake, the final product in the bottle or keg with far less yeast in it is going to have way way way less than the one or two parts per million you started with so with the 10ppm guideline and only having a fraction of a ppm in your final beer I think you should be good to go.

If you are really worried about it I think there are also some more natural oil based anti-foam agents.

There is a non silicon version of Fermcap.

IMO, a lot of people obsess over sanitation to the extreme. I am just relatively careful.
 
DWhitwell said:
So, from all of the input (and thanks to all of you for it), I think I'm going to boil the starter in a pot and chill it in the pot, boil a small amount of water in the flask with the foil to sanitize both and let it cool with the foil on, sanitize a funnel, flame the rim of the pot, add the starter to the flask, drop in the yeast and stir bar, and get it on the plate.

After boiling the water to sanitize the flask you could try pouring the wort in the flask while it is still hot as an added precautionary step for sanitation, not sure if it would react and cause a boil over doing this but it's worth a try.

Also I use a glass Pyrex measuring cup full of sanitizer for the stir bar, when I take the flask off the stove I pour off the sanitizer carefully so as not to pour out the stir bar and then dump the stir bar in the flask while it is still hot as an extra step to make sure the stir bar is also totally sanitary. The stir bars are HDPE which is food grade up to 230 degrees so it should be ok to dump it in the hot water in your flask after you take it off the stove but I wouldn't put it in there while it is still boiling because the glass at the bottom may be too hot.
 
After boiling the water to sanitize the flask you could try pouring the wort in the flask while it is still hot as an added precautionary step for sanitation, not sure if it would react and cause a boil over doing this but it's worth a try.

This is what I do. The only trouble is trying not to spill when you transfer to the flask.
 
My first flask starter was a boil over. What a mess! It hasn't happened since then.

Use a timer to remind you when to pay attention and reduce the heat. I start off at 75% flame and reduce it to around 25% when it gets close to boiling. It will boil at the lower heat setting. Defoamers help, but you can still boil over.

Having a pair of waterproof oven mitts on standby is a good thing to have. If you quickly move the flask off the hot burner, it can prevent a mess. My first boil over continued to spew after shutting off the flame. Moving it off the hot burner stopped it immediately.
 
kh54s10 said:
IMO, a lot of people obsess over sanitation to the extreme. I am just relatively careful.

I sort of agree as in that inexperienced brewers tend to freak out about it and create those "I dropped something unsanitized in my beer, is it ruined?" threads and their beer usually turns out fine. I still think you should take every reasonable step possible to ensure everything is sanitary, especially before your beer has fermented. I am a little more lax after fermentation because the lack of sugars for bugs to eat and alcohol in finished beer act as a safety net against infections. For a while I got more careless and was "just relatively careful" and then had several issues with infections so I went back to the thinking that I really need to be careful about sanitation. I don't go overboard like sanitizing the spoon before stirring the boiling wort in my brew pot but anything that touches the beer is sanitized.

For yeast propagation you need to be extra careful because those few bad bugs that make it into a starter have a better chance of out getting a foothold in the starter than if the same number of bugs made it into a 5 gallon batch. If you get bad bugs in your starter they can multiply and then you are pitching more of them in your 5 gallon batch than you would get if the beer had simply come into contact with a piece of infected equipment such as improperly sanitized tubing.
 
I wonder, though, if returning it to a boil is really necessary. I'm thinking I could sterilize the flasks in the oven, allow to cool with the foil on top, and add the boiled wort to the flask.

Is this what you do with your fermenting vessels?

Why does the flask for starters need to be sanitized so much better than the fermenter?
 
Is this what you do with your fermenting vessels?

Why does the flask for starters need to be sanitized so much better than the fermenter?

Apparently they want to believe they all have a micro biology lab in there house. this is thread is totally over thought. clean and sanitized is perfectly fine for most brewers need. unless you are trying to use a flask that had brett or something similar, which really you should just get separate equipment for. boiling in a flask CAN be dangerous for those accident prone types and even for a seasoned lab tech that gets distracted. if you are working up from a slant or a isolated colony from a plate i would be more careful at first but after the first few steps this level of over thinking a process becomes dubious and stems from paranoia from the lack of familiarity with microbiology and microbiology laboratory techniques.

If i set my house on fire that will sterilize everything.

you see the mole hill........let's make it a mountain.
 
bja said:
Is this what you do with your fermenting vessels?

Why does the flask for starters need to be sanitized so much better than the fermenter?

Soaking the flask in sanitizer is probably enough but boiling some water in it to steam sanitize is even better and easy to do. My last post explained why you need to sanitize more carefully when working with yeast than your actual beer. If your starter gets infected the bacteria or wild yeast have the ability to multiply in your starter meaning you may pitch a lot of off flavor producing bugs into your beer. This is much more likely to produce a beer with off flavors than accidentally infecting your beer because you forgot to sanitize a spoon or your siphon hose because you will most likely be pitching way more bugs than you would get from the un-sanitized piece of equipment.

These numbers are totally made up but used only to explain what i said above better. Lets say your starter got infected with 100 cells of an off flavor producing bacteria and those 100 cells multiply to 1000 cells. This may be enough that your starter tastes funny but if 100 cells multiplied to 1000 in a 5 gallon batch it may not be enough to really affect the flavor. However, if you pitched that infected starter after it multiplied to 1000 cells in your 5 gallon batch they may then multiply from 1000 to 10,000 cells which produce a much more pronounced off flavor in your final beer.

I always pour a little of the starter beer off into a glass and taste it before pitching the starter into the beer as a safety precaution. If the starter tastes off I pitch dry yeast instead. This happened to me a couple times before I got a flask and just used a growler that had a sanitizer soak for starters.
 
Dolomieu said:
Apparently they want to believe they all have a micro biology lab in there house.

Just because you don't have a microbiology lab doesn't mean you shouldn't take reasonable steps to keep things sanitized. I am completely aware of the fact that you are going to end up with organisms in your starters and beer that can potentially spoil beer no matter how well you sanitize. What you are really doing is minimizing the risk that they do spoil your beer by introducing as few of those spoilage organisms as possible. There is a reason it is called sanitizing your equipment rather than sterilizing your equipment, because without having a lab and specialized equipment it will never be truly sterile. Even the yeast we buy at the LBHS has very minuscule amounts of spoilage organisms such as acetobacter in it but it is so little that not enough to really affect your beer. The whole point is to minimize these organisms and as I explained in my previous post minimizing it in starters is far more crucial than in your final batch which has more volume to buffer the off flavors these organism produce.
 
I boil in a pot now and chill the wort in the covered pot. I then pour it into the sanitized flash and add the yeast, then start the stirplate. I don't boil at all in my flask anymore. It is so much easier in a pot.

This
 
Just because you don't have a microbiology lab doesn't mean you shouldn't take reasonable steps to keep things sanitized. I am completely aware of the fact that you are going to end up with organisms in your starters and beer that can potentially spoil beer no matter how well you sanitize. What you are really doing is minimizing the risk that they do spoil your beer by introducing as few of those spoilage organisms as possible. There is a reason it is called sanitizing your equipment rather than sterilizing your equipment, because without having a lab and specialized equipment it will never be truly sterile. Even the yeast we buy at the LBHS has very minuscule amounts of spoilage organisms such as acetobacter in it but it is so little that not enough to really affect your beer. The whole point is to minimize these organisms and as I explained in my previous post minimizing it in starters is far more crucial than in your final batch which has more volume to buffer the off flavors these organism produce.

I realize what you are getting at. Its been a while but I did work in micro lab. I really believe that for our purposes you are really over stating the issue. I also understand the difference be sterile and sanitized. A good wash and soak in San star will works just fine for us that aren't white labs. Again if you are working up from a plate or slant more precaution is advisable.
 
You don't need to hold a boil for any length of time. I just stand there watching and pull it off the stove when it reaches boiling. Easy peasy.
 
I put a temp probe in my flask and set the alarm for 200°. I don't have to watch it that close just be close by. If using an electric stove I kill the heat then and there is usually enough heat left in the burner to bring it to a slow boil for 30 seconds. On a gass burner I set the alarm temp a little higher.
 
kh54s10 said:
I boil in a pot now and chill the wort in the covered pot. I then pour it into the sanitized flash and add the yeast, then start the stirplate. I don't boil at all in my flask anymore. It is so much easier in a pot.

+1^
Also metal conducts better so cooling is faster in the sink afterward. Just dunk everything in starsan and pour the cooled wort in. Much easier
 
I'm also in the boil-then-transfer camp. Actually, I don't even use a flask. I have a huge glass flower vase from Wally World for 3 bucks. It's about 4 L, open top, and covered with foil. Works great. Unless you're boiling in the flask, there's really no reason to absolutely have an expensive borosilicate flask.
 
The way I do it is I hold the whole time, until the boil happens and stabilizes. I have a pair of fire fighting gloves that I used to use at the firehouse. You can grab a cheap pair for $30-40. Well worth it for other activities too (cooking, grilling, bon fire action). Just hold it by the flame and pull when you need to.
 
I use a drop of fermcap in my flask and never have problems anymore. Last few batches have been dry yeast though. Love us05. So easy not having to worry about a starter.
 
I gave up on boiling in the flask.

I measure my water in the flask then pour 90% of the water into a SS pot (my original partial boil kettle). I bring the flask to a boil and then cover with foil and set aside. Much happier with this method and have had no issues.
 
Sorry to revive one of last weeks threads but I thought of something to add that was not mentioned. If you brew all grain you can do what I did and make a big batch of starter wort from grain and then use a pressure canner to make sure the wort is absolutely sterile (to avoid botulism). It will take up a day pressure canning it all but you can do other things while it is on the stove boiling. The great thing about it is next time you make a starter you don't even have to boil the wort. You just sanitize your flask and stir rod and pour the sterile wort which should be at room temperature already directly from the canning jar to the flask and add your yeast and you are good to go. It's nice because there are no boil overs and you don't have to spend 40 minutes prepping a starter every time you want to brew. If you don't have a pressure canner you can often find them on Craigslist or at thrift stores or garage sales. Make sure you get one that can hold at least 4 quart jars.
 
Pressure canning wort is exactly what I do. I borrow a canner from my mom that will hold 7 quarts of wort and can away! It is SO much easier to get a starter going and the canned wort can be stored in the cabinet at room temp.

I also "can" water to sterilize and use it for rinsing yeast that I plan on saving.
 
Pressure canning wort is exactly what I do. I borrow a canner from my mom that will hold 7 quarts of wort and can away! It is SO much easier to get a starter going and the canned wort can be stored in the cabinet at room temp.

I also "can" water to sterilize and use it for rinsing yeast that I plan on saving.

Just an update on the whole boiling flask issue: after reading the sticky on yeast slanting, I decide to give it a try, since I have all of the equipment except the vials and agar. Went through Cynmar and picked up 24 vials, but because they have a $25 minimum, picked up an alcohol lamp to use instead of the candle mentioned in the sticky, and a nichrome loop to use instead of the paperclip, which took me to $25 and change, plus another $10+ for shipping.

Anyway, since I have to sterilize the vials and media in a pressure cooker, I just pressure canned some wort at the same time using the process from the Maltose Falcons, and will use that instead of making fresh wort each time I make a starter.

Boil in a flask. Pfffft.
 
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