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The secret to pouring a smooth beer? Keep your eye on the vacuum, physicist says
Phys.Org ^ | 09-12-2013 | Provided by University at Buffalo

Posted on 09/12/2013 8:32:07 AM PDT by Red Badger

Hong Luo doesn't drink beer himself—he's allergic to alcohol. But Luo, chair of the University at Buffalo's physics department, knows all about the secrets of pouring a smooth brew. That's because it's just basic physics.

"You see so many things in everyday life that seem simple, but if you look at the physics more closely, it's really quite neat," he said. "There's science everywhere."

So as fall gets underway and tailgating parties abound, drink safely and take note: Cans with significantly wider mouths or two holes—which some brands are newly marketing—really do cut down on foam and awkward glugging, Luo says. It's not just an advertising gimmick.

Though most people know this intuitively, they may not be knowledgeable about the science behind why this happens.

Allow Luo to fill you in.

The first concept to understand is atmospheric pressure. In a nutshell, the atmosphere of the Earth—all the air molecules floating around us—exerts a force that pushes on objects.

To demonstrate how this works, Luo sometimes shows his classes a simple experiment: He fills a mug to the brim with water, caps it with a smooth glass plate, holds the pieces tight, flips the whole contraption upside down and lets go. The water will stay in the mug. Why? The pressure that the atmosphere exerts is enough to keep the plate pushed up against the water.

"Atmospheric pressure is quite strong," says Luo, who teaches an undergraduate seminar titled, "Who Needs Physics in the Real World?" "It's enough to hold 10 meters worth of water. You don't feel it because your body is used to the pressure, but it's there."

What does this have to do with drinking beer?

As liquid exits a can, it leaves behind a vacuum—a totally empty space in which you won't find anything, not even air molecules.

"Once you create this vacuum, the atmospheric pressure is going to push air in," Luo says. "It's a dramatic effect: Each time you drink, you create a small vacuum, and the atmosphere responds by pushing air in." (This is the same, simple principal many modern pumps rely on: They push air out of a space, creating a vacuum that air or water rush to fill.)

A super-wide hole or a second hole placed some distance away from the first enables this pressure equalization to occur without obstructing the beer leaving the can, Luo says.

As such, when it comes to getting an unbubbly pour, today's single-hole, pop-top beer cans may be inferior to old-time counterparts like those seen on the hit show Mad Men, which required revelers to punch a hole on each side of a smooth lid—one for drinking, the other for taking in air. Luo hasn't seen Mad Men (he's more of a fan of the Big Bang Theory, a show that features physicists prominently), but he says the old-fashioned beer cans sound like winners.

One last important question: What would happen if you drank beer in a vacuum?

Nothing much, Luo says. The mini-vacuum drinkers create by sipping on beer would just stay inside the can.

But worries about beer would probably be the least of your concerns in such a situation, Luo adds.

"If you've ever seen the movie Total Recall, Arnold Schwarzenegger dreams he landed on a planet where there was no air, and his eyeballs came out," Luo says. "That may not actually happen, but your body may swell."

"Here on Earth, you don't feel the atmospheric pressure because our bodies have an inside pressure that's the same as the outside," he says. "But when you suddenly put someone in a vacuum, that inside pressure is still there, but the outside pressure is gone."


TOPICS: Food; Health/Medicine; Science
KEYWORDS: alcohol; ale; beer; liquor

Image: John White

Okay, who has the BEER PING LIST?.............

1 posted on 09/12/2013 8:32:07 AM PDT by Red Badger
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To: Red Badger

I always enjoy a beer when the wife is doing the vacuuming.


2 posted on 09/12/2013 8:35:05 AM PDT by Cowboy Bob (Democrats: Robbing Peter to buy Paul's vote.)
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To: Red Badger

“As liquid exits a can, it leaves behind a vacuum—a totally empty space in which you won’t find anything, not even air molecules.”

I’m not sure that’s quite right. As the liquid exits the can, the air in the can must expand to fill the extra space, and the pressure in the can is reduced to something lower than atmospheric pressure....and this creates the effect. Its a partial vacuum.

The total vacuum the reporter describes would suck your lips right off.


3 posted on 09/12/2013 8:40:04 AM PDT by lacrew (Mr. Soetoro, we regret to inform you that your race card is over the credit limit.)
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To: Red Badger

Ah, the science behind shotgunning a beer


4 posted on 09/12/2013 8:41:29 AM PDT by NonValueAdded (Henceforth, the Office of the President shall be known as IMPOTUS)
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To: Red Badger

5 posted on 09/12/2013 8:43:31 AM PDT by 1rudeboy
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To: lacrew

Sounds like the perfect definition of a politician:

“As words exit the man, it leaves behind a vacuum—a totally empty space in which you won’t find anything, not even air molecules.”............


6 posted on 09/12/2013 8:44:52 AM PDT by Red Badger (It is dangerous to be right in matters where established men are wrong. .....Voltaire)
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To: Red Badger

Does anyone remember pouring liquid from a tin can or even the old oil cans? You would punch a hole or holes in the can and 180 degrees from that point you would punch an air inlet hole.


7 posted on 09/12/2013 8:48:42 AM PDT by rey
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To: Cowboy Bob

LOL!


8 posted on 09/12/2013 8:49:24 AM PDT by FrdmLvr
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To: Red Badger

“Yeah! Science!!” — Jesse Pinkman


9 posted on 09/12/2013 8:53:25 AM PDT by ClearCase_guy (21st century. I'm not a fan.)
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To: Red Badger
The secret to pouring a smooth beer? Keep your eye on the vacuum,

Mine's locked up in the closet and I only get it out about twice a year......

10 posted on 09/12/2013 8:56:29 AM PDT by Hot Tabasco (')
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To: Red Badger
Hong Luo doesn't drink beer himself—he's allergic to alcohol.

Let me guess, it makes him giggly and he starts hitting on ugly girls....but they get better looking as the night goes on.

11 posted on 09/12/2013 9:02:10 AM PDT by Hot Tabasco (')
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To: Red Badger
Although I have tasted some sucky beer, I doubt very much there is deep space vacuum in the back of my can.

12 posted on 09/12/2013 9:02:45 AM PDT by BitWielder1 (Corporate Profits are better than Government Waste)
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To: Cowboy Bob

Yeah.....whoever did this research obviously led a sheltered life in college and never shotgunned a beer before.


13 posted on 09/12/2013 9:03:12 AM PDT by wbill
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To: lacrew
I’m not sure that’s quite right. As the liquid exits the can, the air in the can must expand to fill the extra space, and the pressure in the can is reduced to something lower than atmospheric pressure....and this creates the effect. Its a partial vacuum.

The pressure over the liquid beer must be greater than or equal to the vapor pressure of beer.

14 posted on 09/12/2013 9:55:05 AM PDT by Steely Tom (If the Constitution can be a living document, I guess a corporation can be a person.)
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To: All

Turn ‘Das Boot’ when you see the air bubble.


15 posted on 09/12/2013 10:42:37 AM PDT by mmichaels1970
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To: Red Badger

Somehow I don’t think this makes much difference when drinking Keystone Light.


16 posted on 09/12/2013 10:51:44 AM PDT by The Great RJ
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To: Hot Tabasco

Ha!

(btw - love your bio...the “local liberal” - now that’s funny!)


17 posted on 09/12/2013 11:00:06 AM PDT by jonno (Having an opinion is not the same as having the answer...)
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To: Red Badger

“Atmospheric pressure is quite strong,”

I realized this once when I was working in a lab that had a vacuum chamber. The operator had started it going, and the “roughing pump” was pumping away. He stated “I left a port plate off, so I’ll have to shut it down and put the plate on.

The absence of the plate left a three inch diamater hole. I put the palm of my hand over the hole, which sealed it and the pressure inside started to drop. In about five seconds my hand became more and more tightly sucked agains the hole. I very quickly calculated what fifteen pounds per square inch would do to my hand, and peeled it off in a hurry.


18 posted on 09/12/2013 11:30:19 AM PDT by Flash Bazbeaux
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To: Red Badger

I’m not worried about beer pouring. That’s for panty-waists. A real man simply chugs it down.

What I want to know is why all the coffee pots dribble coffee all over the place when you pour out a cup. That little lip they have doesn’t give a clean pour a lot of the time.


19 posted on 09/12/2013 12:06:22 PM PDT by wildbill
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To: wildbill

I’ve made that same observation myself. We have had maybe ten coffee makers over the years and every single one drips..............


20 posted on 09/12/2013 12:10:20 PM PDT by Red Badger (It is dangerous to be right in matters where established men are wrong. .....Voltaire)
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To: mmichaels1970

Das Boot? That’s ‘The Boat’ in German..........


21 posted on 09/12/2013 12:12:20 PM PDT by Red Badger (It is dangerous to be right in matters where established men are wrong. .....Voltaire)
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To: 1rudeboy

Parenting at it’s best.


22 posted on 09/12/2013 12:14:30 PM PDT by Dick Cinnamon
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To: The Great RJ

It does about 10 min afterwards, your bladder reminds you why you should not drink Keystone Light.


23 posted on 09/12/2013 12:15:41 PM PDT by Dick Cinnamon
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To: Red Badger

The guy who figures out the science of this and produces a coffee maker that corrects this universal annoyance will make a fortune.


24 posted on 09/12/2013 12:20:55 PM PDT by wildbill
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To: lacrew

There are a few over-simplifications in the article. Your body is “used to” the atmospheric pressure? the junction of your body and the atmosphere is equalized at 14 lbs/sq in. He makes it sound like you just jumped into a swimming pool, and you’re cold at first.


25 posted on 09/12/2013 12:33:09 PM PDT by Cyber Liberty (It's hard to accept the truth when the lies were exactly what you wanted to hear.)
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To: wildbill
What I want to know is why all the coffee pots dribble coffee all over the place when you pour out a cup. That little lip they have doesn’t give a clean pour a lot of the time.

Whoa! I thought it was just mine.........I'm thinking LAWSUIT! You in bro?

26 posted on 09/12/2013 1:15:34 PM PDT by Hot Tabasco (')
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To: Hot Tabasco
Let me guess, it makes him giggly and he starts hitting on ugly girls....but they get better looking as the night goes on.

Luckily, I take allergy shots.

27 posted on 09/12/2013 1:23:04 PM PDT by tnlibertarian (Was Ted Cruz born by c-section? If so, he's not a 'natural born' citizen.)
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To: Red Badger
Hong Luo doesn't drink beer himself

Here's a liitle more about professor Luo:

1. Graduated from HS at the top of his class in China

2. Graduated from the U. of Buffalo at the top of his class, majoring in physics.

3. Never attended a frat party.

4. Never got invited to a frat party.

5. The first and last time he ever drank beer, he got so drunk he ended up sleeping with a butt ugly gal he met in a bar and contracted gonorrhea....

6. Professor Luo blames the gonorrhea as an allergic reaction to beer..........

28 posted on 09/12/2013 1:31:12 PM PDT by Hot Tabasco (')
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To: Hot Tabasco

7. Lost a testicle due to the Gonorrhea, hence his name......


29 posted on 09/12/2013 1:33:35 PM PDT by Red Badger (It is dangerous to be right in matters where established men are wrong. .....Voltaire)
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To: Red Badger

Hong Luo - a man...(doffs hat respectfully)...a man who does not drink and yet dedicates his life to the perfect beer. A saint, surely.


30 posted on 09/12/2013 1:41:05 PM PDT by Billthedrill
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To: Red Badger

Oh, and sorry for calling you “Shirley”...


31 posted on 09/12/2013 1:57:32 PM PDT by Billthedrill
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To: Billthedrill

That’s my uncle........


32 posted on 09/12/2013 1:58:50 PM PDT by Red Badger (It is dangerous to be right in matters where established men are wrong. .....Voltaire)
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To: Red Badger
Das Boot? That’s ‘The Boat’ in German..........

Nein....Das Boot!


33 posted on 09/12/2013 2:04:40 PM PDT by mmichaels1970
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