Using glass-top stove for boiling starters?

[Shawn3997]

Is anyone successfully using their glass-top stove to boil 5L starters? "Successful" meaning no broken flasks. I *really* don't want to have to clean up 5L of boiling wort and broken glass if ya know what I mean. Oh, and buy a new flask.

What about just pouring boiling water into the flask? Would that be more or less likely to break the flask?

 

[pshankstar]

I never boil anything in my flasks b/c I don't want to chance it. I will boil the starter wort in one of my pots that I use for cooking, cool it in the pot then transfer it to my flask. This way there is no worries of a huge mess, stitches or replacing equipment.

I would also worry about dumping boiling water into the flask causing it to break too. You hear of horror stories of glass carboys breaking b/c of thermal shock, I don't even want to risk that with a flask. Just my two cents. Brew on!

 

[Amadeo38]

I have a glass stove top and do the exact same thing as pshankstar and for all the same reasons/fears. Not helpful, but when I had a gas stovetop it was awesome being able to boil right in my Erlenmeyer...although DME has to be added much slower that way.

 

[Upthewazzu]

I boil the wort in a saucepan then pour it into the Erlenmeyer flask and cool it in that. I'm not so much worried about the heat differential b/t the hot wort and cold ice water, but more so the direct heating on the glasstop.

 

[imasickboy]

Here's some useful info from a few years back: https://www.homebrewtalk.com/forum/threads/erlenmeyer-flask-on-electric-stove.148279/

Edit: FWIW, I boil in my flasks, directly on a glass stove, and slide to a cool spot for a few minutes when done, before plopping it in the ice bath.

 

[Indian_villager]

Here's some useful info from a few years back: https://www.homebrewtalk.com/forum/threads/erlenmeyer-flask-on-electric-stove.148279/

Edit: FWIW, I boil in my flasks, directly on a glass stove, and slide to a cool spot for a few minutes when done, before plopping it in the ice bath.

Same here. I have the stir bar in there as well to act as a boiling site.

 

[Amadeo38]

Since reading the other threads linked on this thread, I’ve started boiling directly in my 2L flask on glass top stove with no problems!

 

[BeerChemistWhiskey]

At the lab where I work I boil in erlenmeyers all day, every day. I have never had one break due to thermal shock. A regular practice is to boil ~400 mL for 3 minutes on a ceramic hot plate set to full heat, then pull off to immediately run cold tap water over the glass to cool.

These are Pyrex of course, not sure if all erlenmeyer flasks sold for homebrewing are Pyrex.

I think, within reasonable use, the only way to get one to break would be to boil it dry, or adding cold water to the flask with too little hot liquid already in the flask when heating. Or accidently bump it on something hard .

 

[Andre3000]

I do this all the time with my 3L flask. Careful with the heat though, I've found it's easy to scorch it and get chunks, so I keep the heat at a 2-3.

Also, no need to fully boil it to pasteurize it. I just bring mine to about 170, kill the heat, put some tinfoil on top while it sits on the hot element and a few minutes later, into the ice bath it goes.

 

[kh54s10]

I have boiled on a glass top stove in the flask. But I stopped doing that because it was a PITA. I now boil in a sauce pan, cool it, then add it to the flask. That is so much easier I don't know why anyone boils DME in a flask.

 

[Derp]

I now boil in a sauce pan, cool it, then add it to the flask. That is so much easier I don't know why anyone boils DME in a flask.

I would assume they do it in order to sanitize the flask.

 

[kh54s10]

I would assume they do it in order to sanitize the flask.

Sanitize the flask with Starsan. It is much easier to boil the DME in a pan.

 

[Amadeo38]

I did it because I had done a mixed culture starter (with lacto, brett, pedio) in mine and wanted to make extra sure it was sanitized before using for clean beers again.

 

[madscientist451]

Agree with comment that if you are using extract for a starter, no need to boil it, its already been boiled; just get it hot enough to pasteurize.

 

[Andre3000]

Another tip, I actually blend a portion of the water with the DME to dissolve it, add it to the flask, then top off my final volume as it heats up. Do not blend it fast or it'll foam like crazy. As it warms up the foam really subsides and you can add the water.

This is all just so I know it's well mixed before it goes into the flask.

 

[ddibbern5]

I have a glass top range.
I boil in a sauce pan, cool in my sink with cold water for a few minutes then pour in my sanitized pyrex flask ~+100f when I transfer. I then cool the flask to temps appropriate for pitching.

 

[passedpawn]

Another tip, I actually blend a portion of the water with the DME to dissolve it, add it to the flask, then top off my final volume as it heats up. Do not blend it fast or it'll foam like crazy. As it warms up the foam really subsides and you can add the water.

This is all just so I know it's well mixed before it goes into the flask.

Exactly. You MUST make sure the DME is not thickly caked on the bottom of the flask before you start heating or the flask WILL break.

 

[mongoose33]

I have boiled on a glass top stove in the flask. But I stopped doing that because it was a PITA. I now boil in a sauce pan, cool it, then add it to the flask. That is so much easier I don't know why anyone boils DME in a flask.

Why boil in the flask? Among other things, I don't have an extra pan to clean. Couldn't be easier.

I looked into boiling in a pan before xfering to a flask, and for the life of me, I couldn't figure out the advantage. No extra sanitizing step the way I do it, no extra pan to clean. I stick a long thermometer in the flask prior to the boil so I can easily tell when I've gotten to my pitching temp.

I've boiled on our glass-top stove with both the 2L and 5L Ehrlenmeyer flasks. To cool I just put it in a shallow container of cool tap water, then add ice cubes to the water.

Boiling in the flask for a few minutes ensures it's sanitized, which is another benefit of boiling directly in the flask.

 

[kh54s10]

Why boil in the flask? Among other things, I don't have an extra pan to clean.

I've boiled on our glass-top stove with both the 2L and 5L Ehrlenmeyer flasks. To cool I just put it in a shallow container of cool tap water, then add ice cubes to the water.

Boiling in the flask for a few minutes ensures it's sanitized, which is another benefit of boiling directly in the flask.

For me it is TONS easier to get the DME in a pan than in the flask. I never have to worry about it going volcanic out of a flask. I put the pan in the freezer and monitor the temperature until it is pitching temperature. No messing about with ice.... And it is easy enough to clean a pan. Rinse it out and put it in the dishwasher.

 

[mongoose33]

For me it is TONS easier to get the DME in a pan than in the flask. I never have to worry about it going volcanic out of a flask. I put the pan in the freezer and monitor the temperature until it is pitching temperature. No messing about with ice.... And it is easy enough to clean a pan. Rinse it out and put it in the dishwasher.

I never worry about that, never had a boilover. Why? Fermcap-S. One drop in the flask and no boilovers. Easy peasy.

 

[kh54s10]

I never worry about that, never had a boilover. Why? Fermcap-S. One drop in the flask and no boilovers. Easy peasy.

I stopped using Fermcap-s when 1) I got a boilover even when using it. 2) got a blow-off when using it. 3) saw the FDA recommendation to filter it out.. YMMV.

 

[lump42]

Here's some useful info from a few years back: https://www.homebrewtalk.com/forum/threads/erlenmeyer-flask-on-electric-stove.148279/

Edit: FWIW, I boil in my flasks, directly on a glass stove, and slide to a cool spot for a few minutes when done, before plopping it in the ice bath.

Same here. I have the stir bar in there as well to act as a boiling site.

This is what I do, except I use an old hard drive magnet to pull the stir bar to the top of the liquid. I have neodymium don't want to risk the stir bar being demagnetized by the heat on the bottom. The max operating temp is 248ºF (120ºC). It's still sanitized and provide peace of mind.

For me it is TONS easier to get the DME in a pan than in the flask. I never have to worry about it going volcanic out of a flask. I put the pan in the freezer and monitor the temperature until it is pitching temperature. No messing about with ice.... And it is easy enough to clean a pan. Rinse it out and put it in the dishwasher.

I add the DME to a dry flask, then add cold water with a stir bar. I let the stir bar and plate mix everything up for me before it goes on the directly on the stove. Boil for 3-5 min, then let cool on its own. I use an autoclavable foam stopper and it can sit a few days without any contamination.

 

[kh54s10]

I add the DME to a dry flask, then add cold water with a stir bar. I let the stir bar and plate mix everything up for me before it goes on the directly on the stove. Boil for 3-5 min, then let cool on its own. I use an autoclavable foam stopper and it can sit a few days without any contamination.

May have to try this stirplate method some day. I have added the DME to cold water in a pan and it clumps like crazy. I would think that cold water to the DME would do the same. So I start heating water then add the DME when it is something like hot tap water hot. It dissolves much more easily. I bring just to a boil then cool. That way I know it got hot enough to kill any nasties.

For me it seems so much easier to use a pan. YMMV.