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Author Topic: Why Did My Coffee Just Bubble When I Put A Spoon In It ?  (Read 7802 times)

Offline neilep

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Dearest scientists, academics, engineers, analysts, klevur peeps and Kiwi fruit,

I just made this coffee !




Some coffee I just made !


Ewe'd think it's fairly straightforward ...ewe get your coffee, ewe add some milk then add the boiled water.

but..I added too much milk and so my coffee was not operating within acceptable temperate parameters...so...I whack it in the microwave for a couple of mins and it came out bubbling and kind of extra milky too !

When the boiling subsided I stirred it with the spoon and it immediately frothalised again for a few seconds !!

Why's that then ? Why Did My Coffee Just Bubble When I Put A Spoon In It ?....also...why did the microwave make it more milkyish ?!......is it because the milk was boiled too ?

whajafink ?


hugs and shmishes


mwah mwah mwah



Neil
Je vais Pendre Une Cafe
xxxxxxxxxxxxxxxxxxxxxxx


 

Offline Geezer

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #1 on: 11/10/2011 14:49:39 »
This is one of JP's favorites. He's always rabbiting on about it. What ewe might have done is superheated the water/milk in your "coffee" (quotes because there is only a loose association between that stuff and actual coffee).

When you superheat water, its temperature is at (or possibly even above?) the boiling point of water, which, in London, will be pretty close to 100°C (or 373.15K for the purists), but the water isn't actually boiling. When you stuck your spoon in it, the spoon became a nucleation site that "jiggled" the superheated water and made it boil. Hence the frothing.

That's one possibility anyway. I wonder if it might have happened because your coffee mug stored some of the heat energy from the microwave for a bit then the heat transferred into the coffee and made it boil, but I'm not sure if that's possible. 
 

Offline CZARCAR

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #2 on: 11/10/2011 19:45:43 »
how hot did the mug get? how cold was the spoon?
 

Offline Geezer

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #3 on: 11/10/2011 21:13:27 »
I suppose we might also ask why milk boils over the side of the pan but water doesn't (usually) do that. Or would that be a different question?
 

Offline Geezer

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #4 on: 11/10/2011 21:16:51 »
how hot did the mug get? how cold was the spoon?

Mug 92.64°C
Spoon 283.068°R

(How the heck would he know? He's a sheep!)
 

Offline damocles

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #5 on: 11/10/2011 22:34:12 »
Clearly 'twas a latte with ambition to become a cappuccino
 

Offline Geezer

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #6 on: 11/10/2011 22:46:53 »
If a sheep drinks too much coffee, does it turn into a wooly jumper?

http://www.shaunthesheep.com/games/woolyjumper/
 

Offline neilep

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #7 on: 12/10/2011 05:05:55 »
This is one of JP's favorites. He's always rabbiting on about it. What ewe might have done is superheated the water/milk in your "coffee" (quotes because there is only a loose association between that stuff and actual coffee).

When you superheat water, its temperature is at (or possibly even above?) the boiling point of water, which, in London, will be pretty close to 100°C (or 373.15K for the purists), but the water isn't actually boiling. When you stuck your spoon in it, the spoon became a nucleation site that "jiggled" the superheated water and made it boil. Hence the frothing.

That's one possibility anyway. I wonder if it might have happened because your coffee mug stored some of the heat energy from the microwave for a bit then the heat transferred into the coffee and made it boil, but I'm not sure if that's possible. 

Thanks Geezer !...gosh !..Nucleation !...ewe mean my coffee turned into a power station !...wow !..  ;)
 

Offline neilep

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #8 on: 12/10/2011 05:07:27 »
how hot did the mug get? how cold was the spoon?

Thanks CZARCAR .The mug was hot and the spoon was room temp... unfortunately I was fresh out of mug and spoon thermometers  !  ;)
 

Offline neilep

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #9 on: 12/10/2011 05:08:07 »
how hot did the mug get? how cold was the spoon?

Mug 92.64°C
Spoon 283.068°R

(How the heck would he know? He's a sheep!)

Voila !!...Baaa !!
 

Offline neilep

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #10 on: 12/10/2011 05:10:51 »
Clearly 'twas a latte with ambition to become a cappuccino

Thanks damocles...I'm sure ewe are right...nevertheless..the coffee did have that extra creamy enhancement !...ewe should try it....make a coffee then whack it in the microwave till it boils...it'll be more frothy and milky !  :)
 

Offline neilep

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #11 on: 12/10/2011 05:12:59 »
If a sheep drinks too much coffee, does it turn into a wooly jumper?

http://www.shaunthesheep.com/games/woolyjumper/

My record is 3...now that's a high score !!
 

Offline Geezer

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #12 on: 12/10/2011 08:31:16 »
If a sheep drinks too much coffee, does it turn into a wooly jumper?

http://www.shaunthesheep.com/games/woolyjumper/

My record is 3...now that's a high score !!

You're way ahead of me!

(What a great site! I stumbled on it by googling "wooly jumper". My daughter and I are Wallace and Gromit addicts. I even have a son-in-law called Sean!)
 

Offline damocles

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #13 on: 12/10/2011 08:56:04 »
It is quite possible that the extra "milkiness" is caused by some denaturing or demicellization of the protein casing (... err caesin ...) leading to greater exposure of the fat globules that constitute "milkiness".

I drink my coffee long and weak black.
 

Offline Karen W.

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #14 on: 12/10/2011 09:13:27 »
If a sheep drinks too much coffee, does it turn into a wooly jumper?

http://www.shaunthesheep.com/games/woolyjumper/

I tied your record of 3 on my phone...lol

My record is 3...now that's a high score !!
 

Offline damocles

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #15 on: 12/10/2011 13:55:39 »
Quote
If a sheep drinks too much coffee, does it turn into a wooly jumper?

Here in Oz, woolly jumpers are usually the result of the local 'roos socializing with the flock  ;D
 

Offline Geezer

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #16 on: 12/10/2011 22:44:06 »
Would the coffee go all frothy if you were to dangle your spoon over it for a bit?

(The dreaded Spoon of Damocles.)
 

Offline CZARCAR

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #17 on: 12/10/2011 23:42:28 »
where might the coffe in the mug get superheated?on bottom? then the spoon inserts & provides a thermal conductive metal path from bottom to top ?
 

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #18 on: 13/10/2011 02:48:26 »
I think the Dalek blasted the coffee with its death ray.
 

Offline neilep

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #19 on: 13/10/2011 19:09:29 »
If a sheep drinks too much coffee, does it turn into a wooly jumper?

http://www.shaunthesheep.com/games/woolyjumper/

My record is 3...now that's a high score !!

You're way ahead of me!

(What a great site! I stumbled on it by googling "wooly jumper". My daughter and I are Wallace and Gromit addicts. I even have a son-in-law called Sean!)

I just did 24 because I finally figured you have to click the arrows not move the friggin mouse like the stupid instructions say so !!
 

Offline neilep

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #20 on: 13/10/2011 19:11:33 »
It is quite possible that the extra "milkiness" is caused by some denaturing or demicellization of the protein casing (... err caesin ...) leading to greater exposure of the fat globules that constitute "milkiness".

I drink my coffee long and weak black.

Thanks so much damocles ....I understand what ' weak and black  ' is but what is a long coffee  ?!...thanks again !
 

Offline neilep

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #21 on: 13/10/2011 19:12:39 »
Would the coffee go all frothy if you were to dangle your spoon over it for a bit?

(The dreaded Spoon of Damocles.)

I will try this tomorrow.....I'll stand over my coffee, squat and dangle the spoon from an extremity ! :-)
 

Offline neilep

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #22 on: 13/10/2011 19:13:46 »
where might the coffe in the mug get superheated?on bottom? then the spoon inserts & provides a thermal conductive metal path from bottom to top ?

Thanks also CZARCAR..I do appreciate these answers.
 

Offline neilep

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #23 on: 13/10/2011 19:14:18 »
I think the Dalek blasted the coffee with its death ray.

I exterminated the coffee by drinking it !
 

Offline Geezer

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #24 on: 13/10/2011 19:24:49 »
If a sheep drinks too much coffee, does it turn into a wooly jumper?

http://www.shaunthesheep.com/games/woolyjumper/

My record is 3...now that's a high score !!

You're way ahead of me!

(What a great site! I stumbled on it by googling "wooly jumper". My daughter and I are Wallace and Gromit addicts. I even have a son-in-law called Sean!)

I just did 24 because I finally figured you have to click the arrows not move the friggin mouse like the stupid instructions say so !!

That explains it!

(Crap! Now I can't get the silly tune out of my head!)
« Last Edit: 13/10/2011 19:28:44 by Geezer »
 

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Why Did My Coffee Just Bubble When I Put A Spoon In It ?
« Reply #24 on: 13/10/2011 19:24:49 »

 

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