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Is Sous Vide "Real Cooking"?


coquus
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I'm not sure this communicates the point as well as it should, but here's a picture of a lamb loin I had at StudioKitchen:

gallery_23992_1545_41745.jpg

It was just amazing how it was exactly the same degree of medium rare from the edge to the center, except for a slight ring around the outside where it was seared, for an added dimension of flavor. It was tender, juicy, with an especially intense flavor. You just can't get that same effect on a grill or in an oven. Is it worth the trouble? I thought so, but then I didn't have to cook it, I just ate it.

If you cook your meat properly in a pan/oven or even on the grill, and give it a proper rest, you can achieve the same result (the same degree of doneness throughout the entire piece of meat).

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The thing about sous-vide cooking that I enjoy is the texture of the finished product.  Perfectly cooked protein.  Also the vacuum packing allows the chef to practically inject the juices or any marinade they might wish to use deep into the protein so it retains juiciness and incredible flavor.

With the use of a large syringe, you can literally inject the juices or marinade into the protein...

It works great on roasts (but also any meat), after you take the meat out of the oven, inject some juice (cooking juice, or a flavoured finishing sauce) into your meat just before you rest it, the protein will absorb the juice as it rests (same concept as the juices being re-dispersed throughout the meat as a result of resting).

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Admin: Split from the thread on sous vide recipes.

Is anyone sick of this method, do we really need this type of cooking.  I hate this method.  If you can't cook, try, try again, and you're welcome for the helpful advice.  If you think these fancy methods are going to make you a chef you are dead wrong.

For me, it's just another tool - something to be explored and enjoyed. If it was all I did, over and over again, I'd get sick of it. Hell, if I had to look at the Eiffel Tower everyday of my life, I'd get sick of it too. But right now its 1889 and I'm at the World's Fair!

Peter Gamble aka "Peter the eater"

I just made a cornish game hen with chestnut stuffing. . .

Would you believe a pigeon stuffed with spam? . . .

Would you believe a rat filled with cough drops?

Moe Sizlack

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If you cook your meat properly in a pan/oven or even on the grill, and give it a proper rest, you can achieve the same result (the same degree of doneness throughout the entire piece of meat).

I'm afraid that's not true. Please explain how this is possible if the heat that works its way through the protein being cooked is at a higher temperature than the desired core temperature.

Of course, there is merit to a traditionally cooked piece of protein, but the results are fundamentally different.

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If you cook your meat properly in a pan/oven or even on the grill, and give it a proper rest, you can achieve the same result (the same degree of doneness throughout the entire piece of meat).

I'm afraid that's not true. Please explain how this is possible if the heat that works its way through the protein being cooked is at a higher temperature than the desired core temperature.

Of course, there is merit to a traditionally cooked piece of protein, but the results are fundamentally different.

Maybe if I ever get a camera I can show that a traditionally cooked piece of meat can achieve the same uniform colour throughout. Obviously there is some extra moisture loss compared to sous-vide cooking, but you can still get that nice uniform colour and texture in the meat.

Anyhow, Hervé This explains resting meat, cooking proteins, etc..., much better than I (or anyone else for that matter), I'd suggest reading some of his material. Once you understand what actually goes on inside the meat, you understand why sous-vide works, but also how to improve traditional methods.

Edited by Mikeb19 (log)
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Maybe if I ever get a camera I can show that a traditionally cooked piece of meat can achieve the same uniform colour throughout.  Obviously there is some extra moisture loss compared to sous-vide cooking, but you can still get that nice uniform colour and texture in the meat. 

Maybe this is what people are thinking when they imply that sous vide takes the "soul" out of cooking. When cooking a piece of meat sous vide one can get perfect results every time with almost complete reproducibility, and with a minimal amount of skill -- just follow the recipe and set the temperature correct. Achieving even qualitatively similar results using "traditional" methods, on the other hand, requires a great deal of skill, even if it can be done.

Chris Hennes
Director of Operations
chennes@egullet.org

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Maybe this is what people are thinking when they imply that sous vide takes the "soul" out of cooking. When cooking a piece of meat sous vide one can get perfect results every time with almost complete reproducibility, and with a minimal amount of skill -- just follow the recipe and set the temperature correct. Achieving even qualitatively similar results using "traditional" methods, on the other hand, requires a great deal of skill, even if it can be done.

Very true. There is quite a bit involved in the process, and resting is almost as important as the cooking itself. First you want to bring the meat up in temperature before cooking, then cook it gently in a pan, on a grill, etc..., then rest for at least 10 minutes (for any sizeable cut of meat - large roasts benefit from 20-30 minutes or more - some BBQ competitors rest their brisket for over an hour).

Also, I meant to add in my other post addressed to BryanZ, that the temperature of your oven/water bath isn't the only determining factor in 'doneness' or how well it's cooked or whatever. I mean, if you cook two pieces of meat at 60 degrees C, one sous-vide and the other in an oven without any covering, they're going to turn out different.

Just thought of another example - you put a pot of water on the stove, and bring it to a boil. The water will be a relatively uniform temperature, yet the heat source is only in contact through the bottom of your pot, at a much higher temperature...

Edited by Mikeb19 (log)
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Just thought of another example - you put a pot of water on the stove, and bring it to a boil.  The water will be a relatively uniform temperature, yet the heat source is only in contact through the bottom of your pot, at a much higher temperature...

And a piece of steel the same size will show considerable variation in temperature... the difference between a liquid and a solid. Naturally, a piece of beef has some liquid, but its movement is significantly impeded by the solid portion, preventing the heat from evenly diffusing. The heat must convect in from the outside, with none of the mixing action that is occurring in that pot of water. This is why you let it rest - the outer layers cool a bit and the inner layers warm up, as the heat slowly redistributes throughout the meat. The idea with sous vide is that the redistribution is not necessary: once the core reaches the temperature of the water, the heat is evenly distributed and the meat is "done". With a traditional cooking method, where the temperature of the cooking surface (air, steel, cast iron, etc.) is significantly higher than the desired final temperature of the product, there is no real way to achieve the same results as with sous vide -- there is simply too much temperature variation across the product. If perfect uniformity is the goal, sous vide is the solution. Which is not to say that perfect uniformity should be the goal... but if that is the standard we are setting, then sous vide is going to win that battle every time, by definition.

Chris Hennes
Director of Operations
chennes@egullet.org

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And a piece of steel the same size will show considerable variation in temperature... the difference between a liquid and a solid.

It's actually the difference between a material with a high specific heat capacity (which is also affected by the phase of matter, but water shows a high heat capacity in all phases, highest in liquid), and a material with a low specific heat capacity (steel). But that's a whole other story, I could go on for hours (days?) about physics (before I became a chef I was going to pursue a career as a physicist).

Anyhow, the short point - meat contains lots of water, and organic materials also have a high specific heat capacity. That's why meat is so slow to heat up in an oven, relative to the temperature of the oven itself (liquid water has a specific heat capacity approximately 4 times that of air). Anyhow, the temperature variation is there, but resting the meat allows it to reach equilibrium, and for much of the protein to re-absorb liquid that had previously been expelled. But now we're talking about a cell's ability to hold water, and bio-chemistry isn't my strong suit, but guys like Hervé This are able to explain it much better.

Sous-vide is a slightly more straitforward way of getting the result of a 'perfectly' (a subjective term anyway) cooked piece of meat, and I do like the technique (have used it MANY times in restaurants and at home), but it's not as big a leap as alot of people claim.

Edit - anyhow I find sous-vide really doesn't make a huge difference when you're talking about prime pieces of meat (for instance a rib eye or filet, sous-vide really isn't much of an improvement, I'd argue no improvement to my subjective criteria over traditional cooking), but is put to much better use with tougher pieces of meat, ones that require an extended exposure to heat, which would traditionally be braised (after all, sous-vide is just a form of very low-temperature braising).

Edited by Mikeb19 (log)
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*edit to remove screwy quote formatting*

It seems to me that sous-vide is more of a combination of low-temperature poaching and braising, right? I mean, Alton in his poaching episode and in his first book talks about poaching with the liquid at the desired end temperature. I understand, of course, that this will not be a braise because of the liquid actually being in contact with the protein, but for things like chicken or fish, which would get a short sous-vide anyway, I'd imagine there isn't much difference in terms of texture, at least. Flavor penetration, etc, is of course a different matter. But hey, without the vacuum, no worries about botulism!

Edited by conor610 (log)

"Degenerates. Degenerates. They'll all turn into monkeys." --Zizek on vegetarians

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As a chef, my biggest concern with sous vide cookings is evaporation. When I cook, I count on evaporation to remove the flavorless water from my food as it cooks, concentrating the flavor of whatever I am cooking. Although sous vide may be a more economical approach to cooking and also a better way of retaining moisture and temperature, I am worried that the water that should be leaving the product is actually staying, and (for lack of a better word) diluting the product. What seems like a great way of controlling temperature, seems to me, like a new fangled way of steaming food. And personally, no matter how I try, steaming never really imparts to much flavor into food. But that's just one person's perspective.

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If you cook your meat properly in a pan/oven or even on the grill, and give it a proper rest, you can achieve the same result (the same degree of doneness throughout the entire piece of meat).

I'm afraid I'm with Bryan on this one. What you suggest is an impossibility as a simple matter of physics (unless you were to cook the meat in a pan heated to, say, 60C -- which I hope we can agree is not likely to happen).

...after you take the meat out of the oven, inject some juice (cooking juice, or a flavoured finishing sauce) into your meat just before you rest it, the protein will absorb the juice as it rests (same concept as the juices being re-dispersed throughout the meat as a result of resting).

It's not clear to me that there is any "redistribution" of juices when meat is rested. Rather, the rest serves for the temperature to equilibrate throughout the piece of meat and for there to be an overall reduction in temperature. Also, once meat proteins contract and squeeze out liquid, there's no putting the liquid back in to "reabsorb." You can inject juices into a cooked piece of meat, but it's just going to come running out when you cut into it. Regardless, there is no way that a dry heat method (e.g., cooking in the oven or in a pan) can retain as much moisture as sous vide, or can have as even a level of "doneness." This is somewhat mitigated with LT/LT oven cooking techniques (often employing a steam oven).

As a chef, my biggest concern with sous vide cookings is evaporation. When I cook, I count on evaporation to remove the flavorless water from my food as it cooks, concentrating the flavor of whatever I am cooking. Although sous vide may be a more economical approach to cooking and also a better way of retaining moisture and temperature, I am worried that the water that should be leaving the product is actually staying, and (for lack of a better word) diluting the product. What seems like a great way of controlling temperature, seems to me, like a new fangled way of steaming food. And personally, no matter how I try, steaming never really imparts to much flavor into food. But that's just one person's perspective.

I suppose it depends on what you are cooking and how you are cooking it. Certainly sous vide isn't a technique that works for every single food (there are only a few specific applications for vegetables). For example, some foods are improved by being dried out a little, and sometimes it's nice to have a piece of food that has wide variations in the "doneness" throughout.

However, I've never felt that any foods I've cooked using that method has suffered from "dilution of flavor." Quite to the contrary, actually. When you cook foods in an open container and smell all those wonderful cooking aromas, those are simply flavor molecules that are flying off into the air. Ultimately, that represents lost flavor. When you cook sous vide, those molecules (many of them quite volatile) are trapped in the bag and remain in the finished dish. Cooking sous vide, one actually has to be quite careful about aromatic herbs and spices, or the added flavor can wind up too intense (one short sprig of fresh rosemary in a big bag of 48 hour short ribs will flavor the meat all the way to the bone).

I agree that steaming can often (but not always!) provide a less-than-interesting result, but this is more often than not due to the fact that steaming doesn't produce any maillardization, etc. When one is cooking sous vide, these external flavors are created (either before cooking, after cooking or both) by using a blowtorch, superhot pan or some other method that will quickly cook the outside of the food to the desided degree without having the temperature penetrate too deeply.

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I'm afraid I'm with Bryan on this one.  What you suggest is an impossibility as a simple matter of physics (unless you were to cook the meat in a pan heated to, say, 60C -- which I hope we can agree is not likely to happen). 

Just last night I enjoyed a striploin steak. It had a nice uniform texture and colour throughout the entire piece of meat (minus the seared crust) - just like that picture of the sous-vide cooked lamb. I cooked it under a broiler. It's not impossible - it's just that it takes care to PROPERLY cook a piece of meat using conventional cooking.

Conventional cooking will never be able to replicate the EXACT product that sous-vide can (and vice versa), but you can certainly get a piece of meat that has the same colour (which most people use as the benchmark for 'doneness') throughout, which was the original point I refuted. If you can't get that result, you're not cooking properly.

Also, keep in mind that different cooking mediums (air and water), have different specific heat capacities. If you don't know what specific heat capacity means, in a nutshell, it's referring to the amount of thermal energy a specific amount of a certain material contains. Water's specific heat capacity is approximately 4 times that of air.

When you cook a product containing mostly water (meat), in a water bath, the water is able to transfer alot of energy to the meat, and heat it up to a specific temperature rather quickly. However when you cook meat in an air environment, the differences in specific heat capacity means that the air temperature has to be much higher to provide the same amount of thermal energy to the meat.

It's not clear to me that there is any "redistribution" of juices when meat is rested. Rather, the rest serves for the temperature to equilibrate throughout the piece of meat and for there to be an overall reduction in temperature. Also, once meat proteins contract and squeeze out liquid, there's no putting the liquid back in to "reabsorb." You can inject juices into a cooked piece of meat, but it's just going to come running out when you cut into it.

Well, a scientist with much more experience in this matter than either of us (or anyone else alive for that matter) - Hervé This, disagrees with you. As do many chefs, barbeque enthusiasts, etc..., people who have observed that there is indeed a redistribution of water in the cooked product (myself included).

Try this - take a roast out of the oven and slice it right away. Take a second identical roast, let it rest an hour wrapped in foil and a towel - there will be a difference, and I'm not just talking about the temperature difference...

Edited by Mikeb19 (log)
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I'm afraid I'm with Bryan on this one.  What you suggest is an impossibility as a simple matter of physics (unless you were to cook the meat in a pan heated to, say, 60C -- which I hope we can agree is not likely to happen).

Just last night I enjoyed a striploin steak. It had a nice uniform texture and colour throughout the entire piece of meat (minus the seared crust) - just like that picture of the sous-vide cooked lamb. I cooked it under a broiler. It's not impossible - it's just that it takes care to PROPERLY cook a piece of meat using conventional cooking.

Conventional cooking will never be able to replicate the EXACT product that sous-vide can (and vice versa), but you can certainly get a piece of meat that has the same colour (which most people use as the benchmark for 'doneness') throughout, which was the original point I refuted. If you can't get that result, you're not cooking properly.

If you can show me a picture of a two-inch thick piece of meat that is uniformly medium rare with no gradations of color/doneness and a mailliardized outside with "more than medium rare" penetration of less than 1/8th of an inch (preferably less than 1/16th of an inch) cooked using conventional techniques, I'll believe you. But I've never seen it. This would be easy to do (and I have done it many times) using sous vide and a blowtorch. It this is possible to do under a broiler, I assume it wouldn't be difficult for you to take a picture and post it to this thread.

I also take exception with the idea that anyone who can't achieve dead-on perfect medium rare with extremely temperature sensitive proteins "isn't cooking properly." We're talking about situations in which sometimes a single degree can have an appreciable difference, and even experts using first rate equipment and cooking thousands of iterations of the same dish using the very best and most consistent ingredients available (e.g., the broiler guys at Peter Luger) don't get it just right with anywhere near 100% consistency.

Now, like I said, I think there are plenty of reasons to go for the standard preparations. I'd rather have a Peter Luger-style porterhouse that's blasted under a power-of-the-sun broiler and has gradations of doneness. But I still say that, as a matter of simple physics, it is impossible to get the same uniformity of doneness using a broiler, grill, conventional oven or pan as one can do using sous vide.

It's not clear to me that there is any "redistribution" of juices when meat is rested. Rather, the rest serves for the temperature to equilibrate throughout the piece of meat and for there to be an overall reduction in temperature. Also, once meat proteins contract and squeeze out liquid, there's no putting the liquid back in to "reabsorb." You can inject juices into a cooked piece of meat, but it's just going to come running out when you cut into it.

Well, a scientist which much more experience in this matter than either of us (or anyone else alive for that matter) - Hervé This, disagrees with you. As do many chefs, barbeque enthusiasts, etc..., people who have observed that there is indeed a redistribution of water in the cooked product (myself included).

Try this - take a roast out of the oven and slice it right away. Take a second identical roast, let it rest an hour wrapped in foil and a towel - there will be a difference, and I'm not just talking about the temperature difference...

I'll say these things about that:

1. That any "redistribution of juices" is a secondary effect of temperature equilibration, as food that is hotter on the outside than it is on the inside will have liquids behaving in different ways.

2. I'm not quite sure how it follows that the juices running out of unrested meat proves that the meat juices have "redistributed" (i.e., moved out of some areas of the meat and into other areas of the meat). The effect of more juices running out of a roast that is cut straight out of the oven compared to rested does not necessarily "prove" that "juices have redistrubuted." What it proves is that a roast that is rested has had temperature equilibration and has had an overall reduction in temperature, both of which are condusive to retention of liquids.

3. If, indeed, liquids "redistributed" throughout a piece of meat as it was resting, one would expect that liquid would "redistribute" from the relatively moist center of the meat to those areas of the meat that are dry immediately following cooking (e.g., the well-done areas right below the surface of the meat). This would result in those areas meing moist and juicy instead of dry. Unfortunately, this doesn't happen. Try cutting off that outer bit of meat just under the crust and see for yourself whether or not it's dry or juicy.

4. Now, that said, I do think that there is some movement of liquids within a piece of meat as it rests. I just think that this movement doesn't happen on a particularly large scale and that it may be largely attributable to temperature equilibriation. For what it's worth, proteins cooked to temperature sous vide do not need to be rested.

Edited by slkinsey (log)

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[if you can show me a picture of a two-inch thick piece of meat that is uniformly medium rare with no gradations of color/doneness and a mailliardized outside with "more than medium rare" penetration of less than 1/8th of an inch (preferably less than 1/16th of an inch) cooked using conventional techniques, I'll believe you.  But I've never seen it. 

Well, apparently I'm the only person in the world nowadays without a camera, or a camera phone (or an Ipod, or any of those other mostly-useless gadgets...). I'll try to get around to it though, maybe snagging a camera from some family or friends...

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Who knew that responding to a 4 month old topic would cause such passion.

While I do not claim to know or understand all of the science behind it, I can attest that a pork tenderloin cooked sous vide was unlike any other I have ever cooked. The texture was noticeably different - softer. I am not a pro, but a pretty well accomplished home cook and I have no idea how many tenderloins I have cooked over the years, but I know it is plenty, and this one was better.

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Things like pork loin and pork tenderloin, especially nowadays when pork is so low in fat, are extremely temperature sensitive. One degree C can make a difference. This is one reason these particular cuts of meat lend themselves so well to sous vide treatment.

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When you cook a product containing mostly water (meat), in a water bath, the water is able to transfer alot of energy to the meat, and heat it up to a specific temperature rather quickly.  However when you cook meat in an air environment, the differences in specific heat capacity means that the air temperature has to be much higher to provide the same amount of thermal energy to the meat.

I believe the part I highlighted above is the point of contention. You are obviously saying that you are cooking with temperatures much higher than the desired final temperature. For example, if you have a 2 inch thick steak and throw it into a 130F sous vide bath for a while you'll get a 130F steak. If you take that steak and instead throw it into a 500F oven, how do you get the center to 130F without the layers outside of the center being at a much higher temperature?

If you have a non-sous vide technique for doing such a thing with a steak I would surely like to hear how you do it. Because I don't know any way to do it.

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When you cook a product containing mostly water (meat), in a water bath, the water is able to transfer alot of energy to the meat, and heat it up to a specific temperature rather quickly.  However when you cook meat in an air environment, the differences in specific heat capacity means that the air temperature has to be much higher to provide the same amount of thermal energy to the meat.

I believe the part I highlighted above is the point of contention. You are obviously saying that you are cooking with temperatures much higher than the desired final temperature. For example, if you have a 2 inch thick steak and throw it into a 130F sous vide bath for a while you'll get a 130F steak. If you take that steak and instead throw it into a 500F oven, how do you get the center to 130F without the layers outside of the center being at a much higher temperature?

If you have a non-sous vide technique for doing such a thing with a steak I would surely like to hear how you do it. Because I don't know any way to do it.

Because of a steak's high heat capacity (since it's mostly water, not to mention organic compounds naturally have high heat capacities), it's slow to warm up relative to the environment.

Think about it like this - you can put your hand in a 250 degree oven without much discomfort. Even a 350 degree oven. You can't put your hand in boiling water, you'll get burnt. Why? Because 212 degree water contains ALOT more thermal energy than the same amount of air at 3, 4 hundred degrees. Air is a gentler medium to cook with. Or how about this - I live in a dry climate. Temperatures here can vary between 40 degrees below zero ©, and 35 degrees above zero, and for most of that range it's tolerable. However in humid climates, you FEEL the temperature much more intensely, because the vapour in the air holds alot more thermal energy.

Anyhow, you put your steak in the oven. Does the outside of the steak reach 500 degrees immediately? No, it slowly gains temperature. It also transfers heat to the interior of the steak, raising it's temperature and at the same time cooling (or in this case, slowing the rising of temperature relative to that of the air in the oven) the outside of the steak (to reach thermal equilibrium).

Now, there WILL be a slight difference in outer and inner temperatures initially (the higher the oven temperature, the higher the difference), that's one of the reasons we rest the meat. 10-20 minutes and the whole steak will be the same temperature. Also, theres plenty of biochemical reactions going on inside the steak both while it's cooking and resting. As it rests, water from the centre of the steak moves outward (in an attempt to restore equilibrium). All explained wonderfully by Hervé This in his english book (and I'm sure theres plenty of other sources explaining this). Of course, this requires timing, taking the steak out at the right time, and doing stuff like first raising the temperature of the steak at room temperature.

Cooks are lazy though, with sous-vide, we can throw a dozen steaks in a 60 degree water bath for awhile, then take them out and sear them to the final temperature to order. We can also hold sauces all service long without evaporation, instead of making them to order. Or making soups and vegetable purees, put your stuff in a bag, throw it in water, forget about it all afternoon, pop it in the blender before service.

Anyhow, there is nothing mystical about cooking, the application of heat is nothing but physics, the reaction of the food to the heat is chemistry, biology and physics. I'm really not too interested in explaining anything more about basic thermodynamics.

Also, I'm surprised that in 2007 we're having discussions about sous-vide and whether it's 'real cooking'. It's been around for decades, fine dining restaurants in France have been using the technique since the 1970's and 1980's. I've been using the technique since I was a green apprentice (I had the luck of working with French and Japanese chefs who were very experienced with sous-vide cooking, they'd been using it since before most North Americans even knew what the words meant). The fact that sous-vide cooking is just beginning to be widely accepted is proof of how far behind North American cooks are from Europeans and Japanese. (not to mention spherification techniques are several decades old, the use of agar-agar, lecithin, etc...)

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Sous vide could in the next 5 to 10 yrs make an entry into the domestic market for reheating food.

My microwave does this today.

I love kitchen gadgets but I also think there are too many on the market today. Who needs a separate Magarita making machine?

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"Did you see what Julia Child did to that chicken?" ... Howard Borden on "Bob Newhart"

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Sous vide could in the next 5 to 10 yrs make an entry into the domestic market for reheating food.

My microwave does this today.

I love kitchen gadgets but I also think there are too many on the market today. Who needs a separate Magarita making machine?

Very true. I've already seen/eaten plenty of sous-vide packaged foods (mostly mass produced asian meals and side dishes) you can simply reheat in the bag in the microwave (heck, I had one for dinner last night - most of them are pretty tasty too) - or in a water bath if you wanted I guess.

They're also very nice for camping/backpacking (my favourite hobby) - they pack away very compact, are easy to reheat (boil whole bag in water, or spill out contents and heat up in a pot), and taste a hell of a lot better than dehydrated foods, plus they're more convenient and take up less space than canned items.

Miltary IMPs (Individual Meal Packs) are also vacuum packed, and heated in the bag using a chemical heating device (basically a sleeve you put the IMP into, then activate with a small amount of water).

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When you cook a product containing mostly water (meat), in a water bath, the water is able to transfer alot of energy to the meat, and heat it up to a specific temperature rather quickly.  However when you cook meat in an air environment, the differences in specific heat capacity means that the air temperature has to be much higher to provide the same amount of thermal energy to the meat.

I believe the part I highlighted above is the point of contention. You are obviously saying that you are cooking with temperatures much higher than the desired final temperature. For example, if you have a 2 inch thick steak and throw it into a 130F sous vide bath for a while you'll get a 130F steak. If you take that steak and instead throw it into a 500F oven, how do you get the center to 130F without the layers outside of the center being at a much higher temperature?

If you have a non-sous vide technique for doing such a thing with a steak I would surely like to hear how you do it. Because I don't know any way to do it.

Because of a steak's high heat capacity (since it's mostly water, not to mention organic compounds naturally have high heat capacities), it's slow to warm up relative to the environment.

Mike, here's the thing: you are forgetting thermal conductivity. Water not only has a high heat capacity, but it also has low thermal conductivity (0.609 W/m/K compared to, say, 401 W/m/K for copper). So... you have a piece of 21C (room temperature) beef you want to bring to 54C (medium rare) in a 260C oven. Thermal conductivity says that the outside of that roast is going to be at a much higher temperature than 54C by the time the inside reaches the target temperature, and that there will be a fairly pronounced temperature gradient all the way into the center of the roast. We try to mitigate this temperature disequilibrium somewhat by pulling the roast out of the oven before the inside reaches 54C. When we rest the steak, thermal energy is conducted from the higher temperature outer areas of the steak to the lower temperature inner areas of the steak, and when the temperature equilibrates we hope to have an overall temperature of around 54C. The fact that oven cooking, which transfers heat by a combination of convection and radiation, is extremely inefficient only magnifies this effect. But the bigger the roast and the hotter the oven, the more the outside of the roast will be at a higher temperature than the center of the roast and the more variability in "doneness" throughout the roast will be apparent. This is simple physics.

All explained wonderfully by Hervé This in his english book (and I'm sure theres plenty of other sources explaining this).  Of course, this requires timing, taking the steak out at the right time, and doing stuff like first raising the temperature of the steak at room temperature.

I think you may find that Hervé This was talking about cooking in a low-temperature oven, in which case what he was saying would be correct. Convection/radiation is an extremely gentle cooking method at low temperatures. Not so much at higher temperatures.

Anyhow, there is nothing mystical about cooking, the application of heat is nothing but physics, the reaction of the food to the heat is chemistry, biology and physics.  I'm really not too interested in explaining anything more about basic thermodynamics.

I'm not quite sure what you have explained about "basic thermodynamics" -- except that you seem to have forgotten to account for thermal conductivity, which explains the commonly observed result that the outside of a roast cooked by conventional means (i.e., with a pan, oven or broiler at a significantly higher temperature than the desired end result) is more "done" than the inside of a roast. Again, I say that it is impossible as a matter of basic thermodynamics that it will be any other way.

Edited by slkinsey (log)

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Mike, here's the thing:  you are forgetting thermal conductivity.  Water not only has a high heat capacity, but it also has low thermal conductivity (0.609 W/m/K compared to, say, 401 W/m/K for copper).  So...  you have a piece of 21C (room temperature) beef you want to bring to 54C (medium rare) in a 260C oven.  Thermal conductivity says that the outside of that roast is going to be at a much higher temperature than 54C by the time the inside reaches the target temperature, and that there will be a fairly pronounced temperature gradient all the way into the center of the roast.  We try to mitigate this temperature disequilibrium somewhat by pulling the roast out of the oven before the inside reaches 54C.  When we rest the steak, thermal energy is conducted from the higher temperature outer areas of the steak to the lower temperature inner areas of the steak, and when the temperature equilibrates we hope to have an overall temperature of around 54C.  The fact that oven cooking, which transfers heat by a combination of convection and radiation, is extremely inefficient only magnifies this effect.  But the bigger the roast and the hotter the oven, the more the outside of the roast will be at a higher temperature than the center of the roast and the more variability in "doneness" throughout the roast will be apparent.  This is simple physics.

All of what you're saying is correct. BTW, the reference to Hervé This was just about resting meats and re-injecting liqiuds into it, which he is a strong supporter of. And yes, the larger the roast and temperature difference between the roast and the oven, the more uneven the cooking will be. I'm not going to argue that.

But what I am saying in a nutshell, is this: For a 1 to 2 inch thick steak, you can get beautiful, even cooking using traditional techniques (broiler, oven). The difference in temperature between the outside of the steak and the centre is equalized quickly enough (not to mention the redistribution of water in the meat while resting) that you can get a perfectly cooked steak without resorting to using sous-vide cooking.

Obviously, for a bigger cut like a roast you need to apply a different technique than a 1-2 inch steak. For roasts I usually like to start them out in a very hot oven or in a pan to get a nice crust, then roast them in a slow oven (250-300 degrees).

Anyhow, if thermal dynamics and temperature were the ONLY factors in cooking a piece of meat, sous-vide would win every time. But theres more going on, I'm just saying that between the thermal reactions and the bio-chemical reactions, by taking advantage of knowledge of both you can get a perfectly cooked steak using a traditional cooking apparatus.

PS: Air has a much lower thermal conductivity rating than water, meaning that the steak is going to be conducting heat throughout itself better than the oven will be conducting heat to the air immediately surrounding the steak, making it a gentler cooking method than would appear just by adding up the temperature numbers. (adding to my argument)

Edited by Mikeb19 (log)
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