Just curious if you have experience with pouring boiling water into glass jars?

[Chuck Banshee]

I'm just looking for practical real-world experience.

Today I had a bit of old tea powder left in a Lipton powdered iced tea
jar.

Instead of throwing it out or chipping it out, I simply poured boiling
water into it and drank it from the jar.

Since I half expected the glass jar to break, I did this in the sink -
but to my surprise, the glass held the just-boiled water.

I realize that glass can be made out of many materials (e.g., Pyrex) ...
but I wonder ...

Is this the general experience that typical American glass jars hold up
to boiling water?

[HeyBub]

Dunno in general, but with canning jars (i.e., Kerr) that's how you
sterilize them.

[Betelgeuse]

http://www.youtube.com/watch?v=UyhdMa1ikKM

[Ed Pawlowski]

Glass jars can easily take the 200 or so degrees of hot water. What
will do them in is thermal shock where it is heated too quickly in one
spot compared to other spots. As in a flame, for instance. or
freezer to oven or reverse.

Glass jars are heated fairly high when filled with the contents and
sealed. Heat killing bacteria is what allows it to keep product safe.

[Chuck Banshee]

On Fri, 06 Jan 2012 21:00:46 -0500, Betelgeuse wrote:
> http://www.youtube.com/watch?v=UyhdMa1ikKM

Review:
Over 150 incidents of glass 'bakeware' shattered (some with serious
injuries).

Borosilicon (often made in Europe) versus soda lime (which is more
shatter resistant).

They filled bakeware with dry sand, baked at 450 degrees F for 80
minutes, and then put it on wet graniteand.

The result was that 10/10 times the American-made soda lime bakeware
broke while the European Borosilicon didn't break (but most did at 500
degrees).

Revealingly, the ancient American Borosilicon did last at 500 degrees.

[Chuck Banshee]

On Sat, 07 Jan 2012 01:27:06 +0000, Chuck Banshee wrote:
> Since I half expected the glass jar to break, I did this in the sink -
> but to my surprise, the glass held the just-boiled water.

An unexpected bonus was the fact that the glue under the wrap-around
label heated up enough to be easily balled off with a kitchen utensil.

Maybe we accidentally found a way to remove the under-label glue without
solvents!

[tra...@optonline.net]

> sealed.  Heat killing bacteria is what allows it to keep product safe.- Hide quoted text -
>
> - Show quoted text -

I agree. I've poured boiling water into glass
containers over the years and never saw one
shatter either. I still do it carfully though.
I think the reverse is worse, ie
quickly quenching a hot glass.

[Don Phillipson]

"Chuck Banshee" <chuckb...@private.com> wrote in message
news:je871a$uvb$2...@speranza.aioe.org...

> Instead of throwing it out or chipping it out, I simply poured boiling
> water into it and drank it from the jar.
>
> Since I half expected the glass jar to break, I did this in the sink -
> but to my surprise, the glass held the just-boiled water.

Like most materials, glass expands when heated.
Heat breaks glass vessels when the glass is nonuniform,
i.e. has varying densities at various places. If some parts
expand faster than others, this introduces stresses that
may break the vessel. It is generally supposed that
older glass vessels are more uniform than modern
ones, thus can accept more heat without breaking.

--
Don Phillipson
Carlsbad Springs
(Ottawa, Canada)

[harry]

Thin glass is less likely to break than thick. (Differential
expansion.)

[Joe J]

"harry" <harol...@aol.com> wrote in message
news:deab723f-2974-4e7b...@j9g2000vby.googlegroups.com...

My mother always put a spoon in before pouring. Acts like a heat-sink
maybe?

[Bob F]

I've had them break. If you don't want them to, just pour in a little boiling
water, and swirl/shake it to warm the glass more slowly/evenly. Repeat with some
more water, then fill it.

I watch a fellow gash his hand with a wime glass once. It was fresh from the
dishwasher, filled with red wine. It suddenly broke in his hand while to stood
there holding it.

[Bob F]

I use heat to remove labels frequently.

[Frank]

On 1/6/2012 8:27 PM, Chuck Banshee wrote:

As others point out, it is the thermal stress that breaks the glass.
Pyrex type glass expands less and will take more stress but is too
expensive to use for throwaway jars. The cheap jars if heated slowly and
uniformly to minimize stress will take hot filling. In your case,
adding the hot water slowly with swirling would probably be OK.

Also not a good idea to microwave items in this type glass.

[cl...@snyder.on.ca]

Take that jar out of the freezed and splash some boiling water into
it, and it will react totally differently!!

[natp]

Owens-Corning sold the Pyrex brand name to a company that's now using
it for soda-lime glass (not heat-resistant).

I once canned some peaches and didn't get the air bubbles out of the
jars before putting them in the canner. The bottoms of the canning jars
popped off very neatly, as though they'd been cut with a glass cutter.

[Norminn]

You probably had the lids too tight to begin with...air is supposed to
escape during the canning bath and then the lids seal as the jars cool.
Should tighten before boiling so that the rubber seal barely touches,
not tight. The rings, if separate, are then tightened after cooling.
Test lid with a tap ..

The major issue with any kind of glass is even heating and cooling. One
t'giving, getting the turkey ready, I moved an empty Pyrex pie plate
onto a burner on our glass cook top. Sat down to dinner in the dining
room and a couple of minutes later there was an explosion in the
kitchen. The burner had been left on, and there were long shards of
glass all over the kitchen. Don't want to know what it would have been
like if one of us had still been in the kitchen.

Learned from glass crafting that various glasses have differing COE
(coefficient of expansion, I think)...can put glass in a kiln to melt or
fuse it, but two different glasses to be fused should have same COE or
they cool at different rates and then crack. Took grandson to a
glassblowing class...way cool. He had thought about being a glassblower
but decided to make it just a hobby :o)

[RonB]

It might depend on the "jar". My wife cans vegetables which exposes
the jars to all kinds of temperature changes. Usually the food going
into the jar has been blanched or cooked and is very hot when it goes
in. She puts lids and rings on the jars which allows them to cool
some. Then she puts them in a rack and immerses them in boiling water
for several minutes before putting the jars on the cabinet to cool and
seal. Granted, she uses canning jars for at least 80% of her canning
but she also uses some peanut butter, and other grocery store jars
with good, smooth rims.

RonB

[Chuck Banshee]

On Sat, 07 Jan 2012 12:19:42 -0600, Joe J wrote:
> My mother always put a spoon in before pouring. Acts like a heat-sink
> maybe?

In chemistry we did the same thing (with a glass rod).

I think the purpose is to use surface tension to prevent spills.

[JIMMIE]

Didnt know there was soda glass bakeware made in USA. Pyrex isthe only
glass bakeware I know of.

Jimmie

[John Gilmer]

>
> Like most materials, glass expands when heated.
> Heat breaks glass vessels when the glass is nonuniform,
> i.e. has varying densities at various places. If some parts
> expand faster than others, this introduces stresses that
> may break the vessel. It is generally supposed that
> older glass vessels are more uniform than modern
> ones, thus can accept more heat without breaking.

Well, not all "glass" is the same.

Pure quartz glass has a very low thermal coefficient of expansion.
Standard "Soda-Lime" glass has a relatively high thermal coefficient of
expansion.

The "Boru-silicate" glass features a thermal coefficient of expansion
close to pure quartz. It's advantage over quartz is a MUCH lower
melting point.

The original American Pyrex (r) was a Boru-silicate glass. Apparently,
the owners of the trademark decided that in the US market they would use
"tempered" soda-lime glass in place of the Boru-silicate glass.

The Tempered glass is good stuff. It's very, very break resistant and
is moderately resistant to thermal shock. (It's actually created via a
"thermal shock" process whereby the hot glass surface is suddenly
cooled; another process uses a "case hardening" process when Potassium
(K) replaces Sodium (Na). The potassium atom is a bit larger ad that
places the surface under stress which has the same effect as quickly
"tempering" the glass.

The neat thing about tempered glass is that when it does break it breaks
into small pieces which are unlikely to cause a fatal injury. OTOH,
true Pyrex (r) will, when broken, generate good sized slithers.

The types of lawsuits generated by broken tempered glass are as in the
noise as compared to that generated by broken soda-lime glass.


>

[Robert Macy]

On Jan 8, 7:12 pm, John Gilmer <jlgil...@localnet.com> wrote:
> ...snip...

> The neat thing about tempered glass is that when it does break it breaks
> into small pieces which are unlikely to cause a fatal injury.   OTOH,
> true Pyrex (r) will, when broken, generate good sized slithers.
>
> The types of lawsuits generated by broken tempered glass are as in the
> noise as compared to that generated by broken soda-lime glass.
>

Watch out for broken tempered glass! While external to the vehicle, I
had a front windshield shatter, in moving about the vehicle to
retrieve items on the front seat, I gently brushed my back against the
shattered widnshield. I did NOT even feel the small shards cut through
my shirt and down into flesh until someone pointed out the blood
running down my back. So yes, not fatal, but still as sharp as a
scalpel.

[DerbyDad03]

I've been removing labels from jars by soaking them in warm water for
decades - no, not soaking them for decades, using the soaking method
for decades. ;-)

The water goes right through the paper and dissolves the glue.

For stubborn adhesives or items I can't soak, cigarette lighter (not
barbecue) lighter fluid is my favorite substance. It also soaks
through labels, dissolves the glue and then evaporates.

[N8N]

On Jan 7, 8:23 pm, nob...@voyager.net (natp) wrote:

I've had that happen to me with glass drink bottles - probably bottled
iced tea as you'd buy at a gas station on a road trip or something.
You know how you get that cool "smack" sound when you hit the lid with
the flat of your hand? I just picked up a bottle out of the cooler,
idly smacked it for no real reason, and the bottom of the bottle
popped off and landed on the ground. Fortunately I was not in a car
but standing in a parking lot when that happened. I haven't done that
since :)

nate

[Chuck Banshee]

On Sun, 08 Jan 2012 15:29:53 -0800, JIMMIE wrote:
> Didnt know there was soda glass bakeware made in USA. Pyrex isthe only
> glass bakeware I know of.

The Consumer Reports article implied there is Anchor Hockings and Pyrex
and that Pyrex is no longer made by Corning (if I remember correctly).

[Chuck Banshee]

On Mon, 09 Jan 2012 08:32:38 -0800, Robert Macy wrote:
> Watch out for broken tempered glass! While external to the vehicle, I
> had a front windshield shatter

Is the windshield tempered?

I know the sides are (and they do break into little pieces - ask me how I
know).

But the windshield is laminated I thought. Not tempered.

[JIMMIE]

My HS physics teacher used to do that as a demo. Think its also on
Utube.


Jimmie

[chaniarts]

windshields aren't tempered.

i have buckets of chunks of tempered glass. i can run my hands through
them without any cuts.

[Frank]

I did not see the Pyrex brand on my old canning jars and doubt that they
were Pyrex.

Here's a Wiki link:

http://en.wikipedia.org/wiki/Pyrex

When I worked in a lab, all our glassware was Pyrex. I'd repair or
modify things on occasion but the complicated stuff went to the labs
professional glass blower. It was important to anneal the glass after
modifying to remove stresses. Looking at glass with polarized lenses
can show stress points.

[Daniel Prince]

"Don Phillipson" <e9...@SPAMBLOCK.ncf.ca> wrote:

>Like most materials, glass expands when heated.

Pyrex does not expand much when it is heated. I had two Pyrex one
quart storage bowls (7201 05) that got stuck together. I put ice
and salt in the inner one and put the outer one in very hot water.
The temperature difference was at least 120 degrees Fahrenheit. The
bowls were still stuck together. I did not see any change in
relative size.

I have read (or seen on TV) that Russians often make tea in glass
tumblers. They put a metal spoon in the glass to keep it from
breaking. A silver spoon would conduct heat much better than a
stainless steel spoon but stainless would probably be good enough.
--
When a cat sits in a human's lap both the human and the cat are usually
happy. The human is happy because he thinks the cat is sitting on him/her
because it loves her/him. The cat is happy because it thinks that by sitting
on the human it is dominant over the human.