# Searing Meat does NOT "Lock in the Juices"



## -cp (Aug 22, 2007)

A great blog post here with credited information which dispells the myth of searing...

Welcome to WineFoot.com


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## siduri (Aug 13, 2006)

I've heard this before, and yet...
Meat that's been seared certainly not only tastes better, but *feels* juicier.

I don;t know what happens when meat is seared and when meat is cooked over low flame, but my experience with eating at other people's houses is this:
The many unexperienced cooks whose houses i've eaten at who put cold pork chops or steaks in a cold pan and then turn the heat on low, end up with a pan full of water. Where did that water come from? When i sear the meat i don;t end up with a panful of water.

I can come up with some possible explanations:

Maybe in the end, the water in the meat that's been seared has evaporated rather than leaked out into the pan, and it;s lost anyway. (This is good enough reason to sear it, since who wants boiled steak?)

Or maybe the *outside* of seared meat loses more juice (it certainly is drier on the browned sides) BUT it may also be that the *inside* is juicier, and that would account for the better texture and flavor and *experience *of juiciness. So maybe there is less overall water, but in the unseared meat the water is distributed evenly, so that the experience is that it's less juicy while in seared meat the outside is drier but the inside is more juicy, giving a better experience of juiciness, since you bite through the outside and get to the juicy inside part.
"Juiciness" is an experience, not a criterion that can be measured. We eat for the experience, not for what someone can measure with an instrument. If you dry out the outside and the inside, though smaller, has more juice, it might make the whole piece seem juicier, while if the moisture is distributed evenly, and the inside is the same as the outside, it may contain more moisture, but it certainly *feels* drier.
And who cares if it *is* drier, since we eat for our feel, our subjective experience. It may be drier on the whole, but the *inside* is definitely juicier.


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## eloki (Apr 3, 2006)

Hence the use of a sauce.


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## oldschool1982 (Jun 27, 2006)

Searing *is* a concept/theory and *not* an absolute. As Siduri pointed out the meat "feels juicier" because in a very real sense it is. Searing, like cauterizing, does help close the pores of the meat and allow a good bit of juice to be retained during cooking. But if your expecting the meat to be sealed like a water balloon and basically "explode" with juiciness when you stick your fork in it.....then you'll be disappointed.

The same concept is true for allowing the meat to rest for some time. The juice is not held back like a dam holds water. There will always bee some juice to seep during the resting process.

Also don't forget that like the menu says.............. "The Chef is not responsible for meat cooked above the temperature of Medium. Order at your own risk." This rule *is not* a concept and *is* an absolute.


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## jim berman (Oct 28, 1999)

If you want a great, scientific explanation, check out Harold McGee's On Food and Cooking for a worthwhile explanation. I might have to disagree with "Searing, like cauterizing, does help close the pores of the meat and allow a good bit of juice to be retained " in that the 'hiss and sizzle' you hear when applying heat is mositure coming in contact with a hot surface under the force of pressure. Check out page 112 in the first edition for the whole story.


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## kuan (Jun 11, 2001)

When you sear the meat, the surface loses a lot of moisture. A more definitive test would be to measure moisture content on the outside and in the center.


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## boar_d_laze (Feb 13, 2008)

Searing is an absolute. It creates a Maillard reaction crust on the surface of the meat. The crust TASTES good. 

Also, we like a piece of meat that's well-browned on the outside and barely pink in the middle. It sure looks better than one that is gray through and through. 

The quality of "juiciness" is a result of other factors. Some of which have to do with the way temperatures drive the meat's liquids away from the heat. Also, some have nothing to do with the moisture content of the meat, but with texture and taste. Now, that's subjective.

BDL


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## mezzaluna (Aug 29, 2000)

Here's the thread with Harol McGee. He addresses it nicely. 
http://www.cheftalk.com/forums/open-...-not-sear.html
In short: searing gives you flavor. It does nothing for "sealing" anything.


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## oldschool1982 (Jun 27, 2006)

Don't get me wrong I'm all for searing. Has been a favorite techinque since........ I can't remember when. Probably the first thing I learned after "how to boil water". 

Boar_d_laze, It might be that I could have been able to use different wording but "absolute" has always come to mind when trying to convey a point when it's one of those things that's not perfect and doesn't always perform exactly the way most are led to believe. Subjective came to mind but then it's really not. Maybe it's sort of the cusp between the two. Although, like I said in my original post, if you're expecting the meat to be sealed like a water balloon and basically "explode" with juiciness when you stick your fork in it.....then you'll be disappointed. You are correct. There is certainly a plethora of variables when performing searing. Thickness, cut (strip, rib, round when talking beef) seasoning, temp of product, temp of pan, recovery of temp when product is added, temp while cooking, processing, etc, etc. :roll:

Jim, I will stand by my statement that to sear is, or maybe should is a better choice, be considered......a form of cauterizing. Granted it's not living tissue with a pulse but if you have ever had to cauterize a wound or grabbed on to that pan handle that sat too long over the flame.....you get the same sizzle as you would raw meat on the pan.Maybe I'm reaching here but that's the gist of the explanation I was given so many years ago:look:

I don't know Mezz. Don't mean to sound adversarial about another's point of view but ya know we were al taught that Pluto was a planet that is until last year. I still have a hard time subscribing to the thought process it's not. Sometimes too much thought can be put into something. Not saying that it's right or wrong since the article makes sense. But............ then again......................who am I to contest it.


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## oregonyeti (Jun 16, 2007)

My 2 cents . . whether searing "seals" it or not, cooking meat at a temperature above the boiling point of water makes a big difference. You can't do that if there's water in the pan. Water will keep the cooking temperature lower until it's evaporated.


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## oregonyeti (Jun 16, 2007)

Water requires latent heat to evaporate. If you bring water to the boiling point, it will stay at that boiling point (212 F at sea level), until the water is boiled away. If water isn't allowed to accumulate in the pan, your cooking temp can be higher.


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## boar_d_laze (Feb 13, 2008)

Yeti,

Your reasoning begs many questions. Not saying that you can sear meat in a pan with a significant amount of water, but:

Can the temperature of the pan itself be higher than the BP of water with water present in the pan?

If so, how much higher

If a sufficiently high temperature to sear a given piece of meat in a dry pan, would energy transmitted by contact conduction in a wet pan sear or not?

If not, why not?

BDL


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## oregonyeti (Jun 16, 2007)

All depends on how much water is in the pan. If there are a few spots of water, those spots will be at water's boiling point. The metal of the pan may be at a higher temp, but where there's water it's not as hot.

If you are stir frying something, and the liquid is sizzling as it meets the pan, you are probably cooking at a higher temp.


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## oregonyeti (Jun 16, 2007)

Heat to a cut of meat in a pan will exceed water's boiling point easily if it's a really hot pan. It just has to be more than enough to evaporate any liquid that comes out of the meat.


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## oregonyeti (Jun 16, 2007)

And I think that's the basis of searing meat, the cooking temperature!


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## dannyboy (Mar 9, 2008)

I found this for you guys. I know Wiki has a bit of a bad rap sometimes but this stuff is pretty accurate.

From Wikipedia, the free encyclopedia

Searing (or pan searing) is a technique used in grilling, roasting, braising, sautéing, etc. that cooks the surface of the food (usually meat, poultry or fish) at high temperature so that a caramelized crust forms. A similar technique, browning, is typically used to sear or brown all sides of a particular piece of meat, fish, poultry, etc. before finishing it in the oven. To obtain the desired brown crust, the meat surface must exceed 300 °F (150 °C), so searing requires the meat surface be free of water, which boils at around 212 °F (100 °C).[1]
It is commonly believed that searing locks in the moisture or "seals in the juices" of the food. However, it has been scientifically shown[2] that searing results in a greater net loss of moisture versus cooking to the same internal temperature without first searing. Nonetheless it remains an essential technique in cooking meat for several reasons:
The browning creates desirable flavors through caramelization and the Maillard reaction.
The appearance of the food is usually improved with a well-browned crust.
The contrast in taste and texture between the crust and the interior makes the food more interesting to the palate.
Typically in grilling the food will be seared over very high heat and then moved to a lower-temperature area of the grill. In braising, the seared surface acts to flavor, color and otherwise enrich the liquid in which the food is being cooked.

The belief that searing meat "seals in the juices" is widespread and still often repeated. This theory was first put forth by Justus von Liebig,[2] a German chemist and food scientist, around 1850. The notion was embraced by contemporary cooks and authors including Auguste Escoffier.
Simple experimentation can test the theory: cook two similar cuts of meat, searing one first and not the other. Weigh the end results to see which loses more moisture. (The Food Network program Good Eats carried out such a test in episode EA1H22, Myth Smashers.) As early as the 1930s, such experiments were carried out; the seared roasts lost the same amount of moisture or more. (Generally more, since searing exposes the meat to higher temperatures.)
In short, the meat created by searing is in no way waterproof. Moisture in liquid and vapor form can and does continue to escape from a seared piece of meat. For this reason, searing is sometimes done at the end of the freezing process to gain the flavor benefits of the caramelization as well as the benefits of cooking for a greater duration with more moisture.

Hope that helped! Lol


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## luc_h (Jun 6, 2007)

Are you guys up for an experiment!!

Here is an interesting twist (cooking technique) in the searing steak debate:
khymos.org

Luc H.


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## cat man (May 7, 2007)

The article is very interesting but I'm not so sure there's enough information to truly qualify the stated results.

Different meat cuts have variables that need to be addressed and included.
Tenderloin has a different moisture/protein ratio than sirloin, especially the top cap (coulot).

I believe there is a direct corelation between moisture levels and shrink during cook. Fat content and marbling dispersion also come in to play.

The internal cook temp is also a variable. MR vs MW will certainly produce different shrink levels and percentages.

Also, the amount of moisture/humidity surrounding the meat while cooking will contribute to differing results as well, along with the cubic space to meat ratio.

Think about putting one single ribloin in an alto sham, vs loading it with nine whole loins. The shrink percentage is much higher for one than it is for nine. (I know this for a fact). The reason for this is that the moisture needed for creating a 90%+ humidity level (required by the FDA for low temp roasting) comes from the loin itself.

I guess what I'm saying is that I'm not so sure that the information about the effects of searing on shrink levels is conclusive.

Cat Man


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## boar_d_laze (Feb 13, 2008)

If this thread were started thirty years ago, it might make some sense to keep arguing against _those_ who believe "the conventional wisdom, 'searing seals in the juices.'" But, is there anyone on the planet who still argues that Liebig and Escoffier were right as a matter of science? That was debunked long ago.

It seems to me we're talking about the right ways to handle certain meats. Searing is all about surface texture and sweetness -- in other words the Maillard reaction. It's not about saving some measurable quanta of meat juice. It's interesting to note that in the _sous vide _"experiment" described in the above link, the person conducting the test did sear the meat -- if only after it was cooked. Otherwise the steak would have _appeared_ unpalatable and its taste would have been wildly compromised. That is, no sear = looks bad + tastes bad.

What have we learned from a positive standpoint? That we can combine searing and slow-cook ing? Sorry, already knew that. How long have we been pan-roasting? That we can slow cook first and sear afterwards? Knew that too. It's been common barbecue technique for putting some surface interest on "low and slow" cooked meats, especially problematic surfaces like chicken skin, since long before I was born. And I'm middle-aged.

Of more interest to me would be a discussion on the benefits and liabilities of "resting" meat after cooking. Now _that's _misunderstood!

BDL


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## cat man (May 7, 2007)

BDL
I too would be interested in learning more about the resting process.
While I practice it, I'm not really sure of the true benefits.
I'm also perplexed, to a certain degree, why many chefs insist on bringing lamb to room temp before cooking as well. Personally, this freaks me out a little, just from a simple food safety standpoint.

Cat Man


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## siduri (Aug 13, 2006)

I don't care how much the meat WEIGHS nor how much water is ACTUALLY in it,. what concerns me is how it FEELS, that is my EXPERIENCE of juiciness. if it's an illusion, who cares, i eat for taste and feel and not to please a scientific instrument. Now, that said, let's try the taste test!
In my small way, i've done the taste test many times at houses of people who put the meat in the cold pan and then turn on the heat. It tastes dry. I'd have to be convinced that it actually tastes juicier to give up searing. Now true, the test i refer to is not scientific, and the meat cooked like that lets out moisture and ends up boiling in the pan, which makes it tasteless and dry. But who has tested it scientifically, but with their own taste and texture experience, rather than with a scale.?


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## kuan (Jun 11, 2001)

Here's what I want to see. Take two pieces of meat. Sear one and not the other. Cook to the same temperature. Measure moisture content internally. This will avoid weighing the obviously dryer seared part of the meat.


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## boar_d_laze (Feb 13, 2008)

kuan,

It's been done many times. Searing does not prevent moisture loss. Other, but not all, cooking methods are more effective at keeping the moisture in. However, the quanta of liquid in one piece of meat compared to another is not necessarily determinative as to which is the better steak. 

BDL


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## kuan (Jun 11, 2001)

So how did they control for the seared part of the meat which was obviously dry, or drier?

Seriously I don't know how you can control for that short of taking a core sample.


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## boar_d_laze (Feb 13, 2008)

kuan,

Sorry. I misunderstood you. The question you asked relates only to the interior portion of the meat, and I responded based on a mis-reading in the belief that you asked about the entire steak -- exterior _and_ interior.

I don't know whether the measurements that interest you have ever been taken. However, based on experience -- a well seared steak is preferable to one which has been cooked in another way. If handled correctly, such a steak will certainly _seem_ juicy. To the diner, her subjective experience is everything, and to he*ll with absolute moisture content.

Regarding combining slow cooking with browning -- it's not particularly important which is done first. In fact, if smoking is part of the process, it's better to smoke first because partially cooked meat will not take on smoke as well as cool, raw meat.

BDL


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## siduri (Aug 13, 2006)

My question to you food scientists is this: when i've seen people cook meat by putting in the cold pan then heating it, the pan gets filled with water. If the pan is hot before the meat goes in it doesn't.
how do you explain that?


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## luc_h (Jun 6, 2007)

Hi Siduri,

Before I answer your question can you answer this one:

What will happen if you place a paper cup full of water in a 500F oven?
a) the cup will burst into flames in less then 30minutes and water will spill everywhere
b) the top edge of the cup will burst into flames
c) the water will boil and the cup will stay intact

Luc H.


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## cat man (May 7, 2007)

I'm thinking the cold pan method just lets you see the moisture before it evaporates, but the hot pan is sizzling away the moisture so you don't see as much

Cat Man


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## luc_h (Jun 6, 2007)

Excellent answer!!!!

(btw the cold pan method is a method I never heard about)
Luc H.


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## cat man (May 7, 2007)

Luc
I don't know any experienced cooks who would start in a cold pan either (unless you were cold smoking of course) and in certain cases would add to the risk of foodborne illness because of more time in the danger zone.

This is a bizarre, yet intriguing thread.

I think the answer to your question about the water in paper cup is....(could be wrong but...)

the water will evaporate long before the cup burns. I think the cup would ignite only once the humidity got low enough inside the oven. I am also assuming there is no heat conductor other than ambient air, meaning oven rack etc)


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## cat man (May 7, 2007)

Allow me to expand on this a little...
As the water temp rises, assuming the paper cup is full, some water will spill over as it expands. keeping the cup full and moist. The water inside the cup will also keep the paper cup itself from getting to hot to burn....for a while...once the water is gone, and the humidity inside the oven is low enough....i think the paper would burn at 500 degrees.


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## luc_h (Jun 6, 2007)

Correct again The Cat.

As long as liquid water is in contact with the paper, the paper will not burn (even if it rested directly on the oven rack). When water boils, it maintains a constant temperature of 100C (212F) (at sea level of course). Similarly, water in the freezer will stay at 0C (32F) until all of it turns to ice before going colder. 
We know these points as boiling point and freezing/fusion point. 

The principle applies in cooking. If liquid water is present, regardless of the heat applied to the pan, if the food is in contact with the water it will cook at 100C. If for example the pan is very hot and a steak is placed in it then the water in the meat vaporizes quickly and steams away from the surface. What happens is a thin layer of meat is dried. The water that was there is gone in steam and push towards the colder environment inside the meat. 
Meat proteins usually like to hold on to water but if cooked at high heat they denature (goes from red to gray). Denatured proteins are insoluble in water hence cannot hold water. A seared surface will always appear dry because it cannot soak up water. 
An extreme example of this is when you make boeuf bougignon and the meat cubes cook way too long. Even if cooked in a liquidy sauce the meat can actually be very dry. Overcooked proteins=cannot hold water.

The problem with the word juiciness in this thread is:
foodies relate juiciness with tenderness, moisture, mouthfeel and flavour.
Scientist relate juiciness to yield i.e. weight before and weight after and calculate how much water is retained.

I understand both camps and there are misconceptions and myths on both side. I have demonstrated how a seared roast beef prior to slow cooking loses more water then a slow cooked roast but is so much better tasting.
A seared surface does not seal the water inside. A lot of water is lost during the searing and not a lot after that because the moisture below the surface is pushed towards the colder center and will stay there until done. The resting time is good to equilibrate the temperature across the whole roast. A even temperature across the whole roast will have an even moisture. Moisture is related to temperature. 

A well seared roast will eventually leak at the surface, if rested too long, because the surface proteins are more severely denatured.

(that was a tad too long an explanation....)
Luc H.


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## kyheirloomer (Feb 1, 2007)

FWIW, as a scout leader we used to, as a stunt, show kids how to boil water in a paper cup. This was over an open fire, mind you, which may or may not have the same effect as an oven.

Wherever water is in contact the paper doesn't burn. That's true. Why, because the flash point of paper is greater than 212F. However, exposed paper (i.e., anything above the water level) did not burst into flame. Instead, it would char, and burn away like that. But never with actual flames. 

I have no explanation for why this is so. But anyone can observe it.


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## boar_d_laze (Feb 13, 2008)

Siduri,

Starting with a cold pan, the meat will appear to sweat as it heats up. Atmospheric water condenses on the upper surface of the meat which is (a) the coolest local region, and (b) below the dew point. The sweat rolls onto the surface of the pan and collects until the pan is hot enough to evaporate it. Also, as the meat slowly heats up, moisture held in the interstitial areas between the cells begins to flow freely and exits the meat through surface pores. In a cold pan the liquid appears as liquid. In a hot pan the protein strands in the liquid contract and form fond -- a semi-solid.



Luc,

As long as there's water in the cup the paper will not burst into flame. This is because the paper transfers the heat energy it gains through convection to the water through contact immersion. Although localized areas of the paper cup vary in temperature, paper is a sufficiently efficient conductor to transfer enough energy to stay below it's ignition temperature. The tendency of systems to equilibrate temperatures is a function of what physicists call The Zeroth Law of Thermodynamics. It's the zeroth because it's so basic and so intuitive. 

Finally, I'd like to correct what seems to be a general misapprehension in this thread. The boiling point for all of the water in the cup is not 212F (100C) -- even at sea level. That is, it won't all suddenly turn to vapor. The BP refers to the liquid/atmosphere interface and not the water below the surface. There, the pressure is higher and the BP rises according to depth. Water can be kept liquid at temperatures significantly above 100C by its own weight, and held in place by the meniscus surface tension alone. E.g., water superheated in a microwave. Under greater pressure, like the cooling systems of nuclear reactor, water can be heated to temperatures in excess of 300C without vaporizing.

Y'all each owe me a drink :beer:
BDL


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## oregonyeti (Jun 16, 2007)

Water won't instantly vaporize at 100 C because there's latent heat needed to boil it away. Latent heat is needed for phase change.

I've experienced superheated liquid water in a very clean pyrex cup when I was making tea. It didn't boil when I expected it to. 8 minutes of microwaving when it would usually boil in 5. When I opened the door of the microwave oven, somehow it got nucleation sites and boiled so furiously that most of instantly turned to steam. It was a good thing I didn't have my hand in there yet. It is regarded as a very rare thing, and I saw this very rare thing myself.

I'm not a chef by any means, but I am educated in chemistry and physics. I'm also very aware of the pressure factor involved in boiling point (or saturation point, as it is often called in my trade). I am an air conditioning technician now, but this is a new career for me at age 45. I worked at Hewlett Packard 17 years.


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## cat man (May 7, 2007)

Sounds like somehow a vacuum environment was created, and when the different air temps and pressures inside the mike and out met, all **** broke loose.


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## oregonyeti (Jun 16, 2007)

I think that's likely Cat Man, now that you mention it. thx. Probably there was higher pressure in there until I opened it up.


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## cat man (May 7, 2007)

Dr/Senor/Mr/Jeffe Luc will tell us for certain....I believe.

I was just guessing, sorta...

To me, this is as much logic (read: zero emotion in decision, emotional factor recognized and accounted for) as it is science, if not more.

Remember, when scientists (religious theologins originally, but same pig, prettier lipstick nowadays) declared their opinions as science? (Luc, this is not a bash on you or your peers at all, but I suspect you know what I mean)

Disclaimer: I'm currently reading World Without End, the Ken Follett sequel to Pillars of the Earth.....so I'm kinda living in the 13th century right now.
The crop harvesting technique storyline is really intriguing

Cat Man


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## cat man (May 7, 2007)

"Finally, I'd like to correct what seems to be a general misapprehension in this thread. The boiling point for all of the water in the cup is not 212F (100C) -- even at sea level. That is, it won't all suddenly turn to vapor. The BP refers to the liquid/atmosphere interface and not the water below the surface. There, the pressure is higher and the BP rises according to depth. Water can be kept liquid at temperatures significantly above 100C by its own weight, and held in place by the meniscus surface tension alone. E.g., water superheated in a microwave. Under greater pressure, like the cooling systems of nuclear reactor, water can be heated to temperatures in excess of 300C without vaporizing."

BDL
I am slightly confused by your post.
The boiling point for all the water in the cup is indeed 100C, exposed or not. Aside from air pressure variables.

Once water molecules reach that temp, things change, period. 
Outside of a contained environment, h2o turns from liquid to gas at 100C (sea level, more or less)

Yes, I understand surface temp vs immersed, but in this scenario we're discussing, immersed becomes surface at some point, eventually.


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## siduri (Aug 13, 2006)

Sorry, the discussion has gone on while i slept - your day is my night - 
anyway, this may well be true. However, once the pan is full of water, the meat boils, and the result is completely different to the palate (for one thing, my guess is the inside cooks through quicker resulting in meat that certainly tastes and feels drier - in the other posts i think someone said that when it's too well cooked protein won;t hold water) in any case, yuck.


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## siduri (Aug 13, 2006)

Yeah, and be grateful you haven't. It's not a "method" - it's what you get when you get invited to dinner around here in practically every house i've ever been in. (italian home cooking is not what it's cracked up to be by any means). Not that they think about it, they just do it. They load a pan up with meat, packed together, because people don;t seem to have more than one frying pan and if they do they don;t have big enough stoves to hold them, and then when it's time to cook it they turn it on (to low usually). I've watched this time and time again when i'm a guest at a friend's house. I have to literally sit on my hands to keep from interfering. Don't get me wrong, i'll eat practically anything, and am grateful to any invitation to dinner both for the company and not to have to do the cooking. But it's a very trying test of my friendship to not say something (like AARGH!!! STOP!!!)

anyway, thanks to all of you for your exhaustive answers.


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## boar_d_laze (Feb 13, 2008)

I'll start by quoting from Wikipedia

I was sloppier with language than I should have been in my previous post, and radically misused the term "Boiling Point." I didn't want to drag the discussion into science jargon. Not a particularly good reason, and confusing too. My bad. That cherry's certainly gone now. I'll try to be more precise.

My point was that there's a temperature gradient within the container itself; and if heat is applied to the bottom of a pan hotter temperatures exist below the surface than at the surface, even though water, at the surface is turning to steam. You see, that heat is going somewhere. The phase change can be retarded below the surface, so not all of it vaporizes instantly at BP -- and can be heated measurably higher. In a deep enough pan, even though roiling, the gradient is enough to serious effect thermometer calibration. I'm sure Yeti, in his professional life, learned to calibrate thermometers by placing the probe just below the surface, and waiting for a full, rolling boil before measuring.

Pressure, and/or containment can come from surprisingly simple sources. Surface tension alone can hold enough pressure for _superheating_.

I'm not sure what Yeti meant when he was talking about "latent heat." I know what the term means, although Yeti's term "heat" is not quite standard, "energy" is. And the term "latent" is archaic. I'm just not sure what Yeti meant. The modern (since the mid 20th Century) term for latent energy is _enthalpic energy._ However Yeti seemed to imply that some special energy other than the energy which brought the liquid to BP is necessary for phase change. If the implication is not just sloppy reading on my part, or sloppy writing on his, then: No. _enthalpic energy_ can be and usually is heat energy from the same source. But it's that extra wee bit (to use a scientific term) the system needs for phase shift after the liquid hits BP temp. Meanwhile the temperature of the liquid at the surface stays about the same. This is a function of the No Free Lunch Law of Energy.

The term "latent" (meaning hidden -- as opposed to "patent" meaning obvious) was originally used, because although heat energy was added to the system, temperatures did not increase. Now that we have a quantum understanding of enthalpy (H = U + pV) we're more precise.

There's some recognition of _enthalpic_ energy in the term _saturation temperature _which is the temperature at which a given liquid hits its _saturation pressure_ and undergoes phase change -- either gaseous or solid. "Saturation" refers is from the energy required for the phase change. I'm not familiar with the term "saturation point" used in this context.

Yeti actually covers a manifestation of these phenomena in his description of the superheated water in the microwave. Superheated means it was super hot. Super as in a lot higher than boiling point. What held it in the container? Surface tension -- the same thing which allows a bug to skate on a pond. Not vacuum or low pressure as you guessed. FWIW, it's not everyday, but not all that uncommon either. The FDA has warnings on microwaves.

Remember the deep pan with the temperature gradient?, with the heat applied to the bottom? As the water is heated, air dissolves out of the water and breaks the surface tension with small bubbles. Then the water at the bottom reaches its BP before the water at the top, some of it turns to steam, which forms bubbles, which then rise to the top, keeping the surface moving and a meniscus from forming.

Educational background seems to have reared its ugly head here, and it's a lane down which we probably don't want to go too far. It becomes competitive, feelings get hurt, CV's get fraudulated, and too many people with too much to offer feel excluded.

At any rate, returning to the intersection of science, educational _bona fides_ and cooking, when I was an undergrad in the late sixties - early seventies, I took Organic Chem from a professor named Calvin. Dr. Calvin was, among other things, a Noble Laureate. He used to laugh about how dumb housewives were because they believed a simmer would cook differently than a rolling boil -- when they were both 100C and obviously, _ab definito_ and _a priori_ would cook just alike. QED, what a maroon! Not to mention an officious, sexist pig.

Finally, I'm not sure if science was ever principally in the hands of "theologians." There were some important "natural philosophers" in the medieval church, but they tended not to be theologians. Not important ones, at any rate. Part of this is due to the shift in Catholic theology from Neo-Platonism to Aristoteleanism around the 13th C. Aristotle's deductive logic was very helpful with math (think Descartes, Pascal), but not with science, _per se_. It's true though that two of the medieval leaders of the inductive revolution in thought which became scientific method, and eventually modern science actually were priests who made important theological as well as natural-philosophy contributions -- Robert Grosseteste and Roger Bacon both of whom argued for "empricism" and induction.

Should I mention that Occam's contribution to science is overrated, and that his "razor," is almost never stated in any way to which he would agree? Or that when people claim to use it, they almost always use it wrong? No? Oh, well.

Important medieval and renaissance contributions were made by non-priests as well. Our modern understanding of European science in the middle ages is that it did go on, and not only in the priesthood. And outside of Europe, the Islamic world was certainly active. Indeed, Europe borrowed heavily both in technology and thought. When it comes to the renaissance, think of Brahe, Galileo and Newton. Not a priest among them. Brahe was an anti-priest if ever there was one. Galileo's relationship with the Church was hardly friendly. Actually Isaac Newton was something of a theologian (very weird, don't ask) if not a priest. But, even looking back from our modern day there was nothing quaint about Newton's renaissance science. Smartest man that ever lived? Maybe. For that matter, Bacon warn't no slouch neither.

Well it's not me,
BDL


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## luc_h (Jun 6, 2007)

Boar_D_laze I will be honest here I have not read your last post completely yet....

I read enough to say this: yes there is a gradient of temperature in depth but in a glass of water or even a deep pot that effect is entirely negligible and of zero consequence in cooking. The main reason why is because water heated from below has convection currents circulating upwards and falling downwards which mixes and creates an even mean temperature throughout a small volume of water relatively speaking. All the water must attain a temperature of 100C (at 1 atmosphere of pressure, sea level) to start the phase change process. Additional heat is required to actively create steam. 

The temperature gradient as per water depth explains extreme conditions like for example, Excessive water temperature (above 100C) around volcanic vents in the the deep ocean.

Super heating conditions happen when the applied heat is less directional like in a microwave where the heat is applied relatively evenly throughout the liquid (little or not convection currents). When this happens, nucleation is the clincher to break the equilibrium for spontaneous burst of bubbles. Water cannot be liquid at above 100C but the conditions in the microwave can trick water into this state. These liquids are flukes and are highly unstable.

Superheated water is like opening a pressure cooker already pressurized: boom. The water inside a pressure cooker is around 120C only because it is under pressure. If you suddenly open the lid and water at that temperature must turn to steam (very quickly).

Siduri,
I have been to those type of dinners... I hear you.. I also sit on my hands.

Luc H.


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## boar_d_laze (Feb 13, 2008)

You're missing the context of the entire conversation. Or at least my part in it.

That is as it may be. However, to move back into the cooking context, you need to discuss whether the surface temperature of a pan with a small amount of water can be at a temperature above water's BP. This goes to a question Siduri originally raised, i.e., whether meat can ever sear in a wet pan. I didn't answer the question because I don't _know_ whether the Maillard reaction is scotched more by the presence of water on the meat's surface interfering with the chemistry of the reaction, by the efficiency of immersion conduction in carrying heat away from the meat, or by the efficiency of immersion conduction in dissipating heat from the pan preventing the surface of the pan directly beneath the meat from reaching the 175C threshold for a (relatively) fast Maillard.

Meanwhile, Yeti answered with what I suspected was speculation. I asked some questions, and the conversation shifted from searing to some of the nuances of BP. Returning to Siduri's question: I speculate some combination of the factors I raised above. Do you happen to _know_?

To return to the scientific _knowledge_ context, you need to address Cat's contention (at least as I understand it) that at 100C+ all water in an open system instantly turns to steam.

Within the context of the conversation this might or might not be interesting (in the mathematical sense of the word -- that is, both true and informative). However, it does not go to Cat's (erroneous) contention that once a water molecule reaches BP temp[slightly restated, but _sic_], vaporization instantly occurs. I attempted to (a) explain that just ain't the way it happens; and, (b) talk about one or two of the reasons it ain't. Also, your expression, "an even mean temperature throughout a small volume of water relatively speaking" is meaningless. Relatively speaking. I think you meant, "within a small volume of water temperature differences from place to place are also small." If so, that's true. However, your explanation of "convection currents," if by which you meant _advection_ was not quite so true. In fact, the principal method of heat transfer in a small volume of water is by the diffusion of Brownian motion. If by "convection" you meant the combination of advection and diffusion then your statement is true, but not informative.

Yeti was circling around this, using the term _latent heat_, although he was a little unclear -- not that I can throw stones. I actually discussed this in the post to which you're responding, using the term _enthalpic energy_. As I said, "No Free Lunch."

That's an extreme example. But the temperature gradient effect is linear. It's just bigger at higher pressures -- doesn't mean it doesn't occur at lower.

Here, your use of the term "convection currents" clearly implies advection to the exclusion of diffusion. Does that apply to your previous use?

When you said, "[C]annot be liquid .... but conditions ... trick water into this state." (?!!) You didn't really say that, did you?

Also, I'm a little unsure about your characterization of "applied heat," in a microwave. A microwave doesn't work by "applying heat," or even heat energy, by which we usually mean energy in the infrared spectrum (003 - 4 x 10^14 Hz) is transferred by contact, radiance, or convection. By definition, microwave energy wavelength does not overlap infrared. That's what makes one micro and the other infra. A microwave oven applies (wait for it) _electro magnetic/I] radiation around 2.45 x 10^9 Hz. The energy cannot be transferred in any way other than radiation. The EMR actually increases the translational kinetic energy of the molecules within whatever it was you stuck in the oven. These molecules express their love as heat. The magnetron shooting said EMR is actually very directional. Very, very directional. It seems less directional though because of the degree of penetration.

Similar in the boom sense, but otherwise different. In the case of a pressure cooker, steam is superheated raising the pressure in the cooking vessel. The additional pressure increases the BP of the water in the vessel so the overall temperatures of both water and steam in the vessel are around 125C. In the case of the microwave, the surface tension of the water alone prevents vaporization. An interesting corollary to superheated fluid is a Bose-Einstein condensate.

We may be getting to a point where the precision in language required is out of proportion to the information which can be conveyed.

BDL
_________________________
Father of a Physics PhD candidate, do you?_


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## oregonyeti (Jun 16, 2007)

Latent heat of evaporation is 540 calories per gram . . this is by no means "just a little bit". Even rapidly boiling water takes quite a while to evaporate.

I'm not sure why Wikipedia calls the term "latent heat" obsolete. It's very much alive and defined.


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## luc_h (Jun 6, 2007)

Ok let me take a break here to reread these last long post and make sure I understand everything before i comment again.
Luc H.


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## oregonyeti (Jun 16, 2007)

I think this thread has morphed into something way different than the original intent. It doesn't have much to do with searing meat any more, and I am an offender. I'll let the seared meat rest.


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## dc sunshine (Feb 26, 2007)

Let sleeping dogs lie, let seared meat rest. Both are better off for it. It keeps their juices inside.


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## chefbbaltzley (Jul 15, 2007)

your totally right. i ****ing cant stand it when i see a beautiful piece of meat ruined by seizing up by having over excessive heat and carelesness due to lack of knowledge of basting and resting


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