Erlynmeyer flask fail

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stephelton

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I had a 5000 ml erlynmeyer flask that I ordered from Rebel brewer. It worked well one time around, then I began heating it for a second time and it broke. There is a large (4 inch diameter or so) hole near the bottom. Fortunately, it was only water that I was heating.

I'm wondering how to prevent this in the future. I was heating on this guy:

http://www.academy.com/images/products/400/0267/0267-40037-0001-P1.jpg
 
Don't immediately put it on full heat. Let it warm up a bit on low, then raise the flame intensity. Just a thought.
 
are you sure that the flask is heat resistant? And even if it is, how fast can it change? I would think that a rapid temp change would cause it to crack and shatter. Untreated glass typically does that.
 
Well the 5L flask on rebel says is borosilicate and can be heated on gas stove. I had a 2L borosilicate flask crack on me for no apparent reason as well. I chocked it up to heating it too fast. Now I just make the wort and cool it. Then pour it in the flask.
 
Maybe a burner that's throwing less than 50,000 BTU's? ;)

A heat diffuser could help in the future. A cast iron griddle big enough to accommodate the flask would do the trick.
 
I would imagine that burner is just too overkill for the glass. I can't imagine it not being borosilicate glass but it still has it's limits.

Now I just make the wort and cool it. Then pour it in the flask.

What is the point of using a flask then? You could simply use a jar or something cheaper than a flask. The whole idea behind the flask is that you are sanitizing it while you boil and sanitize the wort. This becomes even more important when working with small quantities of yeast.

If you are worried about the integrity of the glass you are using simply heat it up like a double boiler. Fill a pot big enough to hold the flask with some room temp water. Place the flask with unboiled wort into the pot and water. Heat the entire thing on the stove. As others suggested you could also use a heat diffuser if you want to use direct heat.
 
Well considering it was replaced for free, then why wouldn't I? It's not like I went out and bought another one. Besides that, most jars/jugs have a highly curved bottom which won't allow me to use a stir plate...
 
Well considering it was replaced for free, then why wouldn't I? It's not like I went out and bought another one. Besides that, most jars/jugs have a highly curved bottom which won't allow me to use a stir plate...

I see, it's a replacement you are using. There are just relatively easy ways to prevent them from breaking. I simply don't want to do more dishes so I like to boil within the flask. Most importantly it reduces the risk of infection.
 
I don't necessarily have to do more dishes. Just throw a jar in the dishwasher after emptying it... I never said I make the wort every time :D
img_0274.jpg
 
If you are worried about the integrity of the glass you are using simply heat it up like a double boiler. Fill a pot big enough to hold the flask with some room temp water. Place the flask with unboiled wort into the pot and water. Heat the entire thing on the stove.

I'd bet the boiling point of wort is not the same as that of plain water. I don't know if it's higher or lower, but if the wort boiling point is higher, then that wouldn't work.
 
Crazy, I just typed in "5000 ml flask heat diffuser" in google and this post was the second result... i posted it only hours ago!

Anyway, I'll entertain the idea of a heat diffuser, but I'm having a hard time finding any more information about such a thing. Can anyone point me in the right direction?
 
My flask is only 2000ml but I go from boiling on the stove top to cooling water bath. It has worked for me twice last week. It makes me a bit nervous now that I know it is not impervious to shocking and cracking.
 
I'd bet the boiling point of wort is not the same as that of plain water. I don't know if it's higher or lower, but if the wort boiling point is higher, then that wouldn't work.

Well if the goal is boiling in your flask, then that is important, if the goal is sterilization, then getting upwards of I think 170 (200 is better/faster) is what is needed to kill the bacteria... I once broke a pyrex 4quart measuring cup by heating it on the stove - At the same time I could get it hotter with a microwave... something about how the heat goes into it.
 
I step up my starters with the flask. Keeping the original yeast starter in the flask and then adding additional wort over the course of a few days. This becomes especially Indispensable when ramping up lager starters.

I am kind of doing this by racking out a liter of yeast and adding a liter of wort to my 2000 ml flask.

Do you have a regimen of stepups figured out for your big flask?

Care to share the timing and stepup schedule?
 
Anyway, I'll entertain the idea of a heat diffuser, but I'm having a hard time finding any more information about such a thing. Can anyone point me in the right direction?

You don't need anything fancy, just something between the heat source and the flame. A large cast iron pan would work. Heck a piece of sheet metal might be enough. In lab use, they are heated with a hot plate, or when an open flame is used, the flask normally sits on a wire mesh, often filled in with a modern asbestos replacement. Plus burners not even close to yours are used
 
I don't necessarily have to do more dishes. Just throw a jar in the dishwasher after emptying it... I never said I make the wort every time :D
img_0274.jpg

+1 I have started to can my starter wort too. It's just a huge timesaver. Make a little beer once and have tons of starter for whenever you feel like using it. No muss, no fuss. Just sanitize the flask and add yeast and a can of wort.

But next I do it I will do a better job of filtering out the hot break. My jars looked much worse than yours. :(
 
Well if the goal is boiling in your flask, then that is important, if the goal is sterilization, then getting upwards of I think 170 (200 is better/faster) is what is needed to kill the bacteria...
Be careful to not confuse pasteurization (161ºF for 15-20 seconds) with sterilization (250º for 15 minutes). Pasteurizing will destroy a majority of bacteria, sterilization should destroy it all.
 
I use a pyrex 2L on my electric stove with a little bit of a trivet built. I wouldn't worry about a pyrex 2L flask.

Speaking of sterilization. The only theoretical true sterilization will occur in an autoclave. I've been thinking about using our big one at school to do up a bunch of wort and divide it up between some jars. My profs let me do a lot as long as I'm not growing human pathogens.
 
lol, human pathogens.

Beer Tip: If you have a pressure cooker/canner, then you have a home brew autoclave. That way if you stop going to school, you can still autoclave at home.

You could also get a personal autoclave like tattooists use, but they tend to cost more and are smaller.

I got a Presto pressure canner at Target for $70 and it does 15psi, which equates to 250* F. it can do 7 quart jars at a time. It's the older version of this without the guage Presto Pressure Cooker - Amazon
 
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I might be lucky but I have done many a starters with 2000ml flask, and I typically go from right from flame to ice bath minus the amount of time it takes me to get a hotglove and piece of foil to cover the top with. No problems for me "knocking on wood".
 
I always get boilovers when I cook directly in my flask. I've switched to a 2G pot and then sanitize funneling it into my flask.

How do you guys avoid boilovers when making a 1.5L starter in a 2L flask? Get a bigger flask?
 
Be careful to not confuse pasteurization (161ºF for 15-20 seconds) with sterilization (250º for 15 minutes). Pasteurizing will destroy a majority of bacteria, sterilization should destroy it all.

Right my bad Sterilization is a higher kill htan sanitation, but again, is sterilization what is needed for a yeast that is going to be pitched in a few days? I think as brewers we sometimes try to get things 100% bacteria free (better than sterilized!) when sanitation is what our goal generally needs to be.

I don't do many yeast starters - probably should, but I tend to buy either dry or smack packs.

I like the making of several mason jars of wort for yeast starter, and can see that sterilization/preasure cooker and canning are needed for that as it might be stored for a while.
 
Damn ive heated mine with direct heat probably close to 50 times and have never had a problem. Maybe their was a production issue or something with it. I would contact them.
 
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