How tough IS Pyrex...

[bottlebomber]

I make starters on the stovetop in an erlenmeyer flask like most everyone else. Then, I put the flask in the sink, and start a somewhat annoying process of using the sink gun to spray around on the sides of the flask with progressively cooler water until im satisified that the flask isn't going to crack, then I fill the sink with cold water and let it sit in there till I can pitch.

What im wondering though is has anyone ever tried plunging very hot Pyrex into quit cool water? I really don't want to risk a $30 dollar flask on it, but I do know the stuff is pretty tough. The cookware can go from freezer to oven im pretty sure, but that's not as much a shock as water.

 

[beninan]

I have never personally done it, but if it's a true Pyrex (borosilicate glass) it should be able to withstand temperature shocks. A guy at my LHBS says he boils his flask on the stove, and directly places the glass in an ice water bath to cool it, with no issues.

Edit: What I do, is boil the flask on the stove, let it sit for about 5 minutes after the boil, then place it in a bath of cold water (faucet temperature cold, not ice cold).

 

[kapbrew13]

Real Pyrex should handle extreme temp changes but I don't risk it. Made in China? I pressure cook starter wort in advance, store in fridge, and take it out to reach room temp when making a starter. Have enough to make 6 2L starters right now.

 

[bottlebomber]

I have never personally done it, but if it's a true Pyrex (borosilicate glass) it should be able to withstand temperature shocks. A guy at my LHBS says he boils his flask on the stove, and directly places the glass in an ice water bath to cool it, with no issues.

One is "Pyrex" and the other is some kind of no name chinese glassware. I might just have to take the risk for the good of anybody who wants to know.

Real Pyrex should handle extreme temp changes but I don't risk it. Made in China? I pressure cook starter wort in advance, store in fridge, and take it out to reach room temp when making a starter. Have enough to make 6 2L starters right now.

Interesting... how long do you feel these starters are good for? I have a pressure cooker. Does it make the wort more sanitary to be heated above 212 or something?

 

[Zamial]

I have a pressure cooker. Does it make the wort more sanitary to be heated above 212 or something?

This one I can answer...With a pressure cooker you may have a "poorman's autoclave" ...depending on how much pressure it will cook at, as follows:

LBS = Temp in F
0 = 212
5 = 220
10= 235
15= 250

Almost all life ends at 250F. silicone, stainless steel as well as some glasses like Pyrex can all be autoclaved.

 

[kapbrew13]

One is "Pyrex" and the other is some kind of no name chinese glassware. I might just have to take the risk for the good of anybody who wants to know.

Interesting... how long do you feel these starters are good for? I have a pressure cooker. Does it make the wort more sanitary to be heated above 212 or something?

I do 15lbs for 15-20 minutes. So everything bad should be dead. I guess I can store it in my pantry if i didn't have the fridge space.

 

[bad coffee]

I totally go stove to ice bath with my flask. It's Kimax borosilicate glass. I have no worries in the world.

I know the old pyrex bakewear was borosilicate. Now it's just plain glass. Lots of reports of people's dishes blowing up. Pyrex is now just a brand name, not an actual classification...

B

 

[strat_thru_marshall]

I also go straight from boiling on the stove top directly into an ice batch. Done it many times. Those borosilicate glass flasks are designed for this kind of stuff.

 

[makomachine]

I also go straight from boiling on the stove top directly into an ice batch. Done it many times. Those borosilicate glass flasks are designed for this kind of stuff.

I think people are concerned about the Chinese origin of many of the home brew flasks people get online. Might be worth a poll to see how many do this successfully.

 

[osagedr]

One is "Pyrex" and the other is some kind of no name chinese glassware. I might just have to take the risk for the good of anybody who wants to know.

Sank you berry much.

 

[Homercidal]

I've always let mine sit on the stove for a few minutes then place in a pan with cold water and add ice after the flask is in there.

Soon as I get a new regulator for my mom's old pressure cooker, I'm doing a large batch of start wort and canning it. No more boiling in the flask. No more chilling in ice.

Just pop the top on that jar of starter wort and pour it in the flask!

 

[kapbrew13]

I've always let mine sit on the stove for a few minutes then place in a pan with cold water and add ice after the flask is in there.

Soon as I get a new regulator for my mom's old pressure cooker, I'm doing a large batch of start wort and canning it. No more boiling in the flask. No more chilling in ice.

Just pop the top on that jar of starter wort and pour it in the flask!

Saves so much time.

 

[bottlebomber]

So the solution is obviously to make starter in bulk, and use it as needed... that sound great, ill have to give it a shot. So are people just boiling or sanitizing canning jars to put it in or what?

 

[BrewThruYou]

I bought a cheapo 2L flask from Northern Brewer for like $22...made in India.

When I first got it, I let it cool on the stove, then put it into warm water, then cool, then ice bath. Now, it's immediately from boiling to ice bath. If it breaks, oh well.

 

[Homercidal]

So the solution is obviously to make starter in bulk, and use it as needed... that sound great, ill have to give it a shot. So are people just boiling or sanitizing canning jars to put it in or what?

I got the pressure canner but had no regulator. So I brewed some wort up on the stove and boiled it for a while to kill everything (well, whatever a 20 minute boil will kill).

I heated water up in some jars in the canner to about boiling temp and then poured the water out and poured the wort in. I heated the jars up in the water until it started to boil, and then placed boiled lids on and screwed them down.

As far as I know nothing bad happened, but for true sterility, you should probably pressure can them with the lid and pounds of pressure to really make sure it's all dead.

It will be SOO nice to be able to pull a jar off the shelf and use it whenever I want to build a starter!

 

[bottlebomber]

Rumors confirmed. Stepping up my starter tonight, I threw caution to the wind and took my Pyrex from boiling to cold water just fine.

 

[bottlebomber]

Fak! Word to the wise, don't have a foam stopper in your flask when you cool it down quickly. Now I gotta figure out how to get this out, and then ill probably boil it again :/

 

[kapbrew13]

So the solution is obviously to make starter in bulk, and use it as needed... that sound great, ill have to give it a shot. So are people just boiling or sanitizing canning jars to put it in or what?

I boil starter wort, pour into Mason jars and put the lids on. Pressure cook at 15lbs for 15+ minutes. This kills everything from my research. So the pressure sterilizes which is better then sanitizing.

 

[bottlebomber]

I boil starter wort, pour into Mason jars and put the lids on. Pressure cook at 15lbs for 15+ minutes. This kills everything from my research. So the pressure sterilizes which is better then sanitizing.

You must put some water in there with the jars though... how much?

 

[eastoak]

i found the outer limits of a 1 liter borosilicate flask. heated it on the stove the poured a bit of tap water in and CRACK! when it's full of hot wort it can handle being quickly cooled but not empty. it was not totally unexpected, i was curious, and i still have a 2 liter and a 4 liter flask to work with.

 

[bovineblitz]

Fak! Word to the wise, don't have a foam stopper in your flask when you cool it down quickly. Now I gotta figure out how to get this out, and then ill probably boil it again :/

hahaha

I lol'd.

 

[bovineblitz]

i found the outer limits of a 1 liter borosilicate flask. heated it on the stove the poured a bit of tap water in and CRACK! when it's full of hot wort it can handle being quickly cooled but not empty. it was not totally unexpected, i was curious, and i still have a 2 liter and a 4 liter flask to work with.

My 1L flask seems to be thinner and weaker than my 2L... and they're made by the same company and came from a laboratory.

 

[jar1087]

Funny you should ask. I recently broke my borosilicate 2000mL flask, although not by putting it into cold water; I just barely tapped it against a ceramic crock that was sitting on my table and bam, the bottom fell out.

Barring freak accidents, I usually boil a small volume of water (~250mL) in my flask to sanitize it and the foil over the top. I then take it off the stove, let it cool for 5-10 minutes and then pour in canned starter wort (~1.5L); since the wort is already cool and a much larger volume then the water, it cools it down to a reasonable starter temperature almost immediately.

 

[rico567]

I've always let mine sit on the stove for a few minutes then place in a pan with cold water and add ice after the flask is in there.

Soon as I get a new regulator for my mom's old pressure cooker, I'm doing a large batch of start wort and canning it. No more boiling in the flask. No more chilling in ice.

Just pop the top on that jar of starter wort and pour it in the flask!

This is the answer. I also use the canning method for water for yeast harvesting. Of course, it helps that I already had the canner, jars, etc. around before any of this came up........

AFA the use of Pyrex, Kimax etc. lab glassware, you'll probably get away with giving it thermal shocks for a while, but given the nature of glass, not indefinitely.

 

[kapbrew13]

You must put some water in there with the jars though... how much?

I put 3 quarts as per direction into the pressure cooker during canning.