Boiling in an Erlenmeyer flask
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Boiling in an Erlenmeyer flask
Well, that was exciting!
Usually I boil the dried malt extract for a yeast starter in a saucepan, transfer it to a jug with a lip, pour it into my 2 litre flask and then dump it in a sink full of cold water to cool.
This time I decided to speed the process and reduce the washing up by boiling the DME in the flask (It's boro silicate, so safe) and going straight into the sink.
One moment there was a litre of malt extract slowly warming on the hob, the next moment there was a fountain of boiling liquid. Messy!!
It turned out about 150ml had ejected itself from the flask, but there was still enough liquid left to pitch the yeast into for a starter.
So, how do I avoid similar excitement next time?
Thanks.
Guy
Usually I boil the dried malt extract for a yeast starter in a saucepan, transfer it to a jug with a lip, pour it into my 2 litre flask and then dump it in a sink full of cold water to cool.
This time I decided to speed the process and reduce the washing up by boiling the DME in the flask (It's boro silicate, so safe) and going straight into the sink.
One moment there was a litre of malt extract slowly warming on the hob, the next moment there was a fountain of boiling liquid. Messy!!
It turned out about 150ml had ejected itself from the flask, but there was still enough liquid left to pitch the yeast into for a starter.
So, how do I avoid similar excitement next time?
Thanks.
Guy
Re: Boiling in an Erlenmeyer flask
You can use product such as this which help. You only need a tiny amount in water and can then add when coming to the boil, give the flask a swirl and it will more or less control it. I keep it in a 50ml spray bottle, it means I no longer get any boil overs when making starters as you have just experienced.
Re: Boiling in an Erlenmeyer flask
Stand there and do not take your eyes off it. Be ready to turn the heat down and whip it away from the heat if it starts to climb to quickly. The other option is a wash bottle so you can squirt cold water at the foam and hope it collapses.
Re: Boiling in an Erlenmeyer flask
Swirl the water around periodically as it comes to the boil, stops layering.
- wally
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Re: Boiling in an Erlenmeyer flask
I find that one drop of Fermcap-S is enough to stop boil overs in a flask on the stove.
Re: Boiling in an Erlenmeyer flask
Patience is the key. I put the water in, then the dme and then give it a good swirl. Then its onto a low heat and every minute or so i give it another swirl. This makes sure all the dme has dissolved. I then continue on a low heat swirling now and then untill it very slightly starts to bubble. The heat then goes up very slightly untill i get a very soft boil. I then let it boil for 10 minutes. Whilst this is going on i have a spray bottle of star san ready. If you get a bit of foam nearing the tip, a quick squirt into the flask instantly drops it back. This can also be done to prevent a boil over.
Re: Boiling in an Erlenmeyer flask
I position flask over 1/4 to half the flame and it rolls the boiling wort and never boils up the flask
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Re: Boiling in an Erlenmeyer flask
Thanks all, much appreciated.
The anti foam stuff from Brew Uk looks interesting. Is it the same as the Fermcap-S, does anyone know? 100ml of it would last me the rest of my life at one drop/starter!
Next time I'll pay much more attention to it and not take any chances now I know how suddenly it can boil over.
Guy
The anti foam stuff from Brew Uk looks interesting. Is it the same as the Fermcap-S, does anyone know? 100ml of it would last me the rest of my life at one drop/starter!
Next time I'll pay much more attention to it and not take any chances now I know how suddenly it can boil over.
Guy
Re: Boiling in an Erlenmeyer flask
I am unsure on dosage comparison / concentration however it seems to be similar as silicone based. I find it very effective as I use it for starters and also in the kettle. Another tip when boiling in the flask is to never add yeast nutrient when boiling
. I add that with the DME before boiling.

Dimethicone (also called polymethylsiloxane or dimethylpolysiloxane) is a silicon-based polymer used as a lubricant and conditioning agent. It functions as an anti-foaming agent, skin conditioning agent, occlusive and skin protectant.
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Re: Boiling in an Erlenmeyer flask
Also helps to get a wire gauze to diffuse the heat.
Ingredients: Water, Barley, Hops, Yeast, Seaweed, Blood, Sweat, The swim bladder of a sturgeon, My enemies tears, Scenes of mild peril, An otter's handbag and Riboflavin.
Re: Boiling in an Erlenmeyer flask
You need the lowest possible heat,it pays to boil some water in a kettle first to dissolve the DME in a jug before adding to the flask and set at the lowest heat.It doesn't matter if it takes a while, and a very gentle simmer for 15 to 20 minutes will do the job .
I buy my grain & hops from here http://www.homebrewkent.co.uk/
I have taken more out of alcohol than alcohol has taken out of me - Winston Churchill
I have taken more out of alcohol than alcohol has taken out of me - Winston Churchill
Re: Boiling in an Erlenmeyer flask
That is exactly what I do. Disolve the DME in a little boiling water pour it into the flask and top up to required volume with more boiling water. Then simmer for 10 minutes.FUBAR wrote: ↑Sun Oct 07, 2018 12:36 amYou need the lowest possible heat,it pays to boil some water in a kettle first to dissolve the DME in a jug before adding to the flask and set at the lowest heat.It doesn't matter if it takes a while, and a very gentle simmer for 15 to 20 minutes will do the job .
"You're not drunk if you can lie on the floor without holding on." Dean Martin
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1. Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in sideways, thoroughly used, totally worn out and loudly proclaiming... "f*ck, what a trip
It's better to lose time with friends than to lose friends with time (Portuguese proverb)
Be who you are
Because those that mind don't matter
And those that matter don't mind
Re: Boiling in an Erlenmeyer flask
If I remember correctly, According to Walter White an erlenmeyer flask is for measuring and mixing, not boiling. 

The Doghouse Brewery (UK)
Re: Boiling in an Erlenmeyer flask
Maybe. But it works fine for boiling and it gets sterilised inside and out during the process
"You're not drunk if you can lie on the floor without holding on." Dean Martin
1. Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in sideways, thoroughly used, totally worn out and loudly proclaiming... "f*ck, what a trip
It's better to lose time with friends than to lose friends with time (Portuguese proverb)
Be who you are
Because those that mind don't matter
And those that matter don't mind
1. Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in sideways, thoroughly used, totally worn out and loudly proclaiming... "f*ck, what a trip
It's better to lose time with friends than to lose friends with time (Portuguese proverb)
Be who you are
Because those that mind don't matter
And those that matter don't mind