427 replies to this topic

[reuvens]

Beefrib "Sous Vide"











1) Rib, 100 g Salt, 2000 ml Water (=5% Brine)...
2) After 24 hours in the walk in, then rinsed for 1 hour...
3) Sous Vide Bag in a 80 C waterbath poached for 12 hours...
4) Just out of the waterbath
5) The meat was absolutely tender with slightly resistance just like it should be...

[edsel]

Vue_de_cuisine,

Your beef ribs match almost exactly the way I did it just two weeks ago. Same time, same temperature, and I even use a Lauda MS with a big stock pot like yours. It's a small eGullet world!

Did you do any "finishing" cooking (to brown the meat) after the sous-vide? I tried it both ways and actually preferred the straight S-V in this case.

A couple of differences: I didn't brine the meat - just enclosed a pinch of salt in the bag. Also, my ribs had a larger cap of fat than the one in your photos. I'd probably do a better job of trimming the meat next time.

Nathan,

Thanks so much for sharing your research with us. I've tried to glean as much information as possible from Roca, Ducasse, and various web references, but I still find it hard to come up with reliable time/temperature combinations other than by trial-and-error. You've done a lot of research on the subject, and it's greatly appreciated.

BTW the table looks fine in my browser - perfectly legible.

[nathanm]

Try the short ribs at 55C for 24-36 hours. You will be amazed.

I will post more tables tonight. Thanks to Dave Scantland (Dave The Cook) for helping fix the formatting problem.

[reuvens]

Edsel:

The Brine is actually necessary as it keeps more liquid inside the meat during the cooking period...

I have to admit that the liquid inside the bag was a little bit too salty for my taste. The meat itself wasn´t at all...

Next project....candied Fruits / Veg "Sous Vide"

Nathanm:

I chose "just" 12 hours as i like a slightly, slightly resistance in the meat texture...

..but thanx again. Your advices are worth gold & diamonds !

[DaleJ]

nathanm: I'm missing something, I'm sure. When I look at your first four settings I see that if I cook at 133F the cooking time is 19 minutes. If I cook at 140F the cooking time is 53 minutes. I'm at a loss to understand this. Help. Thanks.

[nathanm]

The times are Hours: Minutes: Seconds

I think you may be looking at the second and third lines of the table where the time for 56C is 1 Minute, 19 seconds, and the time for 60C is 53 seconds.

Also, note that you need to make sure you are comparing rows which have the same thickness of product. A thicker product takes much more time.

[docsconz]

Nathan, These have to be some of the all time greatest posts on eGullet! Thank you for not only doing the work, but taking the time to share it with us on eGullet. Magnificent.

The one concern I still have with the food safety aspect is a lot of SV cooking temps make for a nice culture medium. It is therefore particularly important that hygeinic techniques re surface cultures be particularly adhered to.

[nathanm]

Glad you like the posts! Yes, you have to be very careful with any kind of cooking.

Cook and hold SV has MUCH more concerns associated with it.

Sous vide at temperatures above 130F/54.4C can be easily food safe. The only issue, as I discuss above, is that if you have a very large piece of food you could have a cooking time so long that there is a problem. Cooking long enough to sterilize is easy.

Cooking fish at 45C/113F is more of an issue - but as long as cooking time is a couple hours or less you are within guidelines. Note that this is only for immediate service not cook and hold.

[nathanm]

Moderator's Note: Please click here to see nathanm's fish cooking table.

Edited by Kitchen Host, 20 July 2008 - 03:21 PM.

[nathanm]

Moderator's Note: Please click here to see nathanm's table for cooking a wide variety of foods started at 5C/41F.

Edited by Kitchen Host, 20 July 2008 - 03:25 PM.

[nathanm]

Here is a little bit more about the big tables for cooking times and temperatures.

As explained in a post above, I generally cook at the lowest temperature setting, or perhaps just one above. So, I will cook at 131F / 55C for a 54.4C /130F final core temp. Joan Roca recommends 65C/149F. I don't know why he prefers the higher temperature - it speeds things up, but not enough that it is worth the various negatives.

Consider a 1 inch / 25mm thick piece of meat cooked to 54.4C/131F. At 55C it takes 41 minutes. At 65C it takes 17 minutes. Unfortunately if you really want the meat to be within +- 1 degrees C (or 1.8 F) then you must time this to plus or minus 50 seconds otherwise you overcook it. This is not the end of the world, but it is easy to mess up this way. And, if your meat is not exactly 25mm, well that makes a variation too. In the 55C case, you just leave it in a little longer and it can't overcook. Not so with the higher temperature bath.

If you want to sterilize it for food safety reasons (which is generally not required for beef steak, at least in the US) then you must use a second bath at 55C becaues it must sit there for an additional 112 minutes (see FDA chart I linked to in a post above) after the core reaches 54.4C/130F. You can't do that with your 65C bath. So, why not cook it at 55C to start with? I will probably write to Roca and ask.

Note that the cooking times depends very strongly on temperature and on thickness. Moving the temperature down 10C (65C to 55C) increases the cooking time by almost 3 fold.

Double the thickness to 50 mm and the 55C time goes to 2.5 hours, 65C time goes to just over an hour. That is a BIG change.

Note that the exact times here are for SV cooking, but the same principle holds for ANY kind of cooking - increasing the thickness, or the temperature differential, radically changes cooking times.

In SV we have an option that does not exist in most other kinds of cooking - we can cut the food to portion size prior to cooking. It is easy to do small vacuum bags that have an individual portion in them. In many approaches to meat cookery thick pieces are used primarily to prevent the center from being dried out or overcooked. That is not an issue with SV.

One big lesson from the chart is that cutting the food thinner radically reduces cooking time. So, rather than increase heat, I tend to cut the food size.

The only reason not to do thin pieces is if the post-SV cooking would be problematic. Many people like to brown or crisp the outside after SV, with a salamander, blow torch, hot pan or other method. A very thin piece of meat is easy to ruin that way. There are also aesthetic and other reasons to have big chunks of food. But the lesson from the tables is that thickness comes a big price.

Edited by nathanm, 05 August 2005 - 08:32 PM.

[Stagiaire]

This is awesome stuff, Nathan!

I was just wondering though....on your column for "rest time" which you define as the time the core temperature stops rising and begins to fall, how far does the core temperature rise? Did you note what the max core temp achieved was? Or am I understanding your table wrong?

Did you work with bone in cuts? Does the presence of the bone, like in a prime rib for example, have a great effect on cooking times? Or do we just measure the thickness of the meat disregarding the thickness of the bone (i.e. measure meat thickness only)?

Btw, it would be important to note, for those that are just casually browsing, that these tables represent minimum cooking times to achieve a target core temp, and does not take into account the time it takes for collagen to break down for tougher cuts of meat such as short ribs, etc. Is there, per chance, a project in the works to tabulate this? :)

I'm sure I'm not alone in saying that you've just garnered superhero status in these parts of cyberspace!

[nathanm]

This is the time for boneless cuts. Bone conducts heat differently than meat (although not as different as you might think.). I did the calibration tests with very uniform cuts of meat so as to keep everything simple.

Bones to one side - like a bone-on rib eye, T-bone, porterhouse are not going to affect the cooking time because the shortest path for heat transmission is not through the bone.

The maximum rise after the rest period is the desired temp - i.e. 54.4C/130F in that table, 45C/113F in the fish table. So, if you take out the meat at the point when the core reaches that temp, it will then overshoot to just reach the temp for the table before starting to drop.

You are correct that this is the minimum time to reach the core temperature. So, for a tender cut like fillet you are done. For a cut that needs collagen break down you need to then add as much time as is required. I do tough beef for 24 - 36 hours at 54.4C/130F. I have done it all the way up to 72 hours. I'll get around to tabulating some of that eventually.

Edited by nathanm, 06 August 2005 - 08:55 AM.

[jackal10]

Now I'm really confused.
I thought the whole point was to put the food in a bath at or about the final desired temperature, and leave it a long time, like until the next day. so the temperature stabilises thoughout That way there is no danger of overcooking, which is great for the chronically disorganised, like me, and the food is uniformly cooked. For all meats that is above 112 minutes at 54.4C, the sterilisation temperature limit specified by the FDA. For me 58C is the ideal core temperature to cook tender beef to. It sort of stands to reason that if the meat proteins are disrupted, then so are the biological processes in bugs.
Tougher cuts, like brisket cooked in BBQ style need more severe treatment, past the "stall" temperature at about 72C/165F

I agree that fish is different, as it cooks below that temperature, and also does not have collagen in the same way that needs to soften.

I'd like to know your thoughts on the other end - what is the maximum length of time you can leave something in a water bath at say 58C? I guess the limits are not bacterial spoilage, but chemical degredation, such as oxidation, or the fat breaking down to rancid components.

Personally I don't like the very long cooked meats - more than 18 hours or so where all the texture has gone, leaving only what seems to me to be meat paste with some hard lumps in it...

Edited by jackal10, 06 August 2005 - 12:25 AM.

[Stagiaire]

Now I'm really confused.
I thought the whole point was to put the food in a bath at or about the final desired temperature, and leave it a long time, like until the next day. so the temperature stabilises thoughout 

Actually, the second your core temp reaches your target temp, the entire piece of meat is AT target temp, assuming your water bath is at target temp.

I guess the limits are not bacterial spoilage, but chemical degredation, such as oxidation, or the fat breaking down to rancid components.

There should be no oxidation as there is no oxygen. The protein is packed in a vacuum bag. Fat shouldn't be breaking down to rancid components as the temp is too low to break down the fat and there *should be* nothing there to turn it rancid assuming you took the necessary precautions during prep. People fry things in animal fat, and that is done at much higher temperatures. As long as you are below the smoke point (which is much much higher than the max temp for sous vide, 212F, then you don't run the risk of breaking down the fat.

Personally I don't like the very long cooked meats - more than 18 hours or so where all the texture has gone, leaving only what seems to me to be meat paste with some hard lumps in it...

Meat should not turn into "meat paste" or breaking down and totally denaturing again due to the low temperature that you are cooking it. One of the main reasons why you cook sous vide is to be able to cook at a temperature low enough that the proteins don't seize up and squeeze out all the juicy goodness out of them.

[jackal10]

There are oxidation reactions within biological chemicals in the meat - not from the oxygen in the air, which I agree mostly excluded, but each other. I'm sure the fat will also slowly degrade, although I don't know how fast.

Although the temperature is low enough for the protein not to degrade and the muscle fibres not to contract, eventually the connective collagen turns to gelatine, and the meat falls apart, As I said, the texture reminds me most of meat paste, or perhaps rilletes, except that there are still hard bits (nerves? small blood vessels?) that have not degraded embedded in it.

Edited by jackal10, 06 August 2005 - 08:21 AM.

[nathanm]

.......

I thought the whole point was to put the food in a bath at or about the final desired temperature, and leave it a long time, like until the next day. so the temperature stabilises thoughout  That way there is no danger of overcooking, which is great for the chronically disorganised, like me, and the food is uniformly cooked.  For all meats that is above 112 minutes at 54.4C, the sterilisation temperature limit specified by the FDA. 

.......

Tougher cuts, like brisket cooked in BBQ style need more severe treatment, past the "stall" temperature at about 72C/165F

...........

I'd like to know your thoughts on the other end - what is the maximum length of time you can leave something in a water bath at say 58C? I guess the limits are not bacterial spoilage, but chemical degredation, such as oxidation, or the fat breaking down to rancid components.

Personally I don't like the very long cooked meats - more than 18 hours or so where all the texture has gone, leaving only what seems to me to be meat paste with some hard lumps in it...

Originally, the primary use of SV was about storage of the food after cooking and before service - cook and hold SV. In that version they used much higher temperatures due to food safety concerns.

More recently immediate service of SV has become the main use - at least in high end restaurants. The idea of cooking in a bath at 55C to get a 54.4C result is pretty recent.

Tender cuts of meat don't need the long treatment, and in fact will eventually become mushy as you suggest.

If 58C is your preference, fine, but remember that with sufficient time you can tenderize other cuts. Brisket, for example, does not need to go to 72C/165F. I have cooked tender brisket at 54.4C/130F - it just takes 36 hours, whereas the reaction is much faster at 72C - a few hours will do.

I am not sure what the limit is. The longest I have cooked anything is 72 hours. I did two experiments - flat iron steak (paleron in French) and beef cheeks. I did that at 54.4C/130F and 57.8C/136F. The flat iron steak was great at 36 hours and too soft at 72 hours. The beef cheeks were terrible, they seem to need more temperature or more time.

When you say cooking over 18 hours is not to your preference, I'd suggest that you try some meat cooked at a lower temperature. The difference between 54.4C and 58C is striking. It isn't just the time - it is the combination of time and temperature. At low temperature (54.4C) I can show you tough meat that is still way too tough at 18 hours.

[nathanm]

The collagen to gelatine transformation is the main thing you are trying to achieve by cooking for a long period of time. However, there are lots of other proteins that are reacting and eventually these reactions will have an affect on the meat.

If you are going to cook for a long time - say 24 hours - then you want a cut with a lot of collagen to begin with.

The same is true if you cook at higher temperatures. If you want to make confit - duck confit, pork, lamb, carnitas whatever - then I cook at higher temperature, because the goal is to achieve a particular effect. I generally cook those at 80C/176F for 8 to 12 hours.

This is similar to the conventional cooking process for them because you are trying to achieve a similar affect. You could cook duck legs for 24 hours (or there abouts - I have only done a couple expermients so far) at low temperature say 54.4C to 58C and get a good result. It would taste good, but it would not be at all similar to traditional duck confit.

But that sort of confit treatment will destroy a tender cut. I do a lamb confit based on lamb shanks cooked SV with oil in the bag for 8 hours at 80C/176F. The collagen in the shank turns to gelatin and the result is great. Put a lamb tenderloin through that and you'd get something terrible.

We have not mentioned what you put in the bag with the meat. That can also break down the meat proteins, so you have to be very careful, particularly for the long cooking times.

[jackal10]

Very interesting. I will have to try at 55C for longer.
Have you tried Brisket, for faux BBQ this way?

I wonder also if these lower temperatures for longer can be usefully applied to other preservation techniques, such as canning (called bottling in the UK).
I have a surplus of fruit such as greengages coming up. Processing at the recommended temperature regime, for example the HMSO handbook recommends 82C/180F for 15 mins, results in overcooked fruit. The FDA guidelines (section 3-401.13) implies 57C/135F, but doesn't specify time, but by analogy with meat of about the same thickness I would guess 40 minutes or so. If meat is safe, and the bacteria disabled after about 4O mins at 57C I wonder if same can be said for fruit? What is the effect on yeasts? Most yeasts in bread making are killed at well below these temperatures, so it may be OK.

[Boris_A]

The longest I have cooked anything is 72 hours.  I did two experiments - flat iron steak (paleron in French) and beef cheeks.  I did that at 54.4C/130F and 57.8C/136F.  The flat iron steak was great at 36 hours and too soft at 72 hours.  The beef cheeks were terrible, they seem to need more temperature or more time.

I did the beef cheeks too (the Ducasse recipe at 54C/72h) and I found them relatively firm as well, though not terribly (and they developped a taste not unlike tongue, BTW). For several times, I did veal breasts (tendrons de veau) at 62C/ 19-24 h and found the results to be uneven.

My general impression is that the quality of the raw material is very important with SV cooking over extended time. Maybe the cheeks of a well stored/matured Charolais beef is a different matter. For me, beef cheeks are difficult to obtain (on order only) and I presume they came directly from the slaughterhouse with absolutely no storage. I have to try to get some first class material - for cheeks and for tendrons as well.

[Stagiaire]

Nathan,

You might want to try the cheeks at 170F for 8 hours. Prior to cooking sous vide, marinate them first overnight in white wine, mire poix (onions, carrots, leeks cut into fairly large chunks due to the cooking time). Then dry the cheeks, season, dredge in flour, brown them and cool them down. In the vacuum pouch go the cheeks, 1x mire poix, 1x white wine, 3x veal stock. Vacuum seal then into the water bath or combi they go. Good stuff.

[docsconz]

A question of technique- How does one manage to vacuum seal liquid without making a huge mess?

[nathanm]

vacuum sealing a liquid depends on your vacuum machine.

On consumer level machines that do edge sealing (like FoodSavr), liquid can be a mess. One techique to control that is to freeze the liguid into ice cubes first, then it seals just fine.

Professional chamber style machines can take liquid directly. However, if you put too much in, or are not careful, you can still make a mess. The liquid will boil when the vacuum hits its peak and that can cause it to boil over. So, you have to be careful to not put too much in the bag, and then watch it to shut the vacuum off if it starts to boil over.

In fact, I store all of the stock I make in vacuum bags.

[nathanm]

Very interesting. I will have to try at 55C for longer.
Have you tried Brisket, for faux BBQ this way?

I wonder also if these lower temperatures for longer can be usefully applied to other preservation techniques, such as canning (called bottling in the UK).
I have a surplus of fruit such as greengages coming up. Processing at the recommended temperature regime, for example the HMSO handbook recommends 82C/180F for 15 mins, results in overcooked fruit. The FDA guidelines (section 3-401.13) implies 57C/135F, but doesn't specify time, but by analogy with meat of about the same thickness I would guess 40 minutes or so.  If meat is safe, and the bacteria disabled after about 4O mins at 57C I wonder if same can be said for fruit? What is the effect on yeasts? Most yeasts in bread making are killed at well below these temperatures, so it may be OK.

Yes, I have tried brisket and it comes out very good, although not with the barbeque flavor. One could do a two stage process to get that.

Joan Roca makes "smoked" fish by taking a smoke infused oil, and the cooking things in it sous vide. He does this with fish primarily. Might work with something else.

The canning question is more complicated.

For short duration, in the presence of oxygen there is no problem. As one example, there are two ways to pasteurize milk - HTST (high temperature, short time) and LTLT (low temperature low time). LTLT is generally defined as 30 minutes at 143F/61.7C. It is an approved method for dairy product pasteurization.

The primary caveat is that canning must be able to kill botulism spores. The botulism organism Clostridium botulinum dies easily - it is not hard to kill. The spores are more resilient however. In food served immediately, the spores are not a problem - they are not harmful to eat, and the organism cannot grow in the presence of oxygen which is surely present during service and consumption. However, in canning, or in cook and hold SV, there is the potential opportunity for the spores to grow and produce the bacterium, which then produces the toxin which is what makes you sick or kills you. It is the long term storage, without oxygen, that makes canned food susceptible - basically the bacterium dies during sterilization / pasteurization, but the spores can survive and grow if the are in an anoxic situation.

As a secondary issue, canning generally seeks to achieve a 10D to 12D reduction in bacterial population - that is a 10 to the 12th reduction. FDA food safety is generally 6.5D to 7D, and many experts concede that 5D is enough. So, the times would wind up being longer even besides the spore issue.

Those are the primary differences between canning and food safety for immediate service.

You also ask what the difference is between meat and fruit - the main issue there is pH, some bugs live in specific pH ranges. You can kill them outright with the right pH and not need heat at all, or more generally pH changes the time you need to kill the spores. Acidic foods are in general much lower risk. There are also some proteins present in beef and other meats that can allow botulism spores to survive even in low pH. So to be really certain you need to have empirical data relevant to the conditions under which you are operating.

An alternative approach is to sterilize the food a second time after canning. The botulism toxin is destroyed by heat - 10 minutes at 170F is supposed to be enough. So, cooked food that is meant to be cooked to that level.

Here is some background on botulism:

http://edis.ifas.ufl.edu/FS104

Here is a very good explanation of the math behind the thermal death curves for botulism, and how it applies.

http://www.nzifst.or....htm#thermdeath

Using this approach you could design a process for canning. However to be sure you have to look at the factors like pH, and other things that may affect survival. If you look hard enough on the web you may find somebody has done this already.

Two final warnings here, which contradict one another.

First, you take your life in your hands when you cook, at all, and especially so with home canning. You need to be careful before you adopt a new approach to make sure that it is really going to work and not make you sick or kill you or your guests.

Second, because of this dire risk, most of the information you find on the topic is wildly exaggerated. People tend to "round up" the actual amount of time by adding one safety factor after another with the result that the actual consumer level advice is not really to be trusted - it has been exaggerated "for your own good" to a point that is often excessive and wildly out of keeping with the actual science. Last year there were 169 cases of botulism in the US, some from wounds and other sources, and very few of them fatal. Meanwhile about 40,000 people die from car accidents. If the same worry were applied to cars we would be told not to drive over 10 MPH. That might actually be good for us, but I don't anybody would be accept it.

So, the lesson of these two is that you have to be informed by the best science and then you need to take the level of risk you feel comfortable with.

Also, remember that ANY food safety guideline can be undone by a stupid mistake like dirty fingernails or other poor hygiene practices.

[tan319]

A question,
Even though I've been around cryovac machines (pro chamberstyle machines, correct?), I've never spent time working wih them or hanging out around them.
How do they take liquid directly?
Thanks in advance.

[edsel]

Ted, the chamber machines can do liquids because the vacuum is applied to the entire chamber, not just the pouch.

With a clamp machine (FoodSaver) the pouch is exposed to the atmosphere, so as the air is sucked out the surrounding air pushes in on the bag. If there's any liquid content it will get pushed into the machine. That's why you have to freeze liquids and chill fats so that they're solid if you're working with a FoodSaver.

With a chamber machine there's no air outside of the bag to push on it - the whole chamber is under vacuum. When a chamber machine is doing its thing the pouch just sits there rather than collapsing. After the air is removed the sealing bar closes and seals the open end of the bag. Then the machine releases the vacuum - it's at that point that you'll see the bag collapse.

[Really Nice!]

Last Thursday I did a duck breast at 143°F for 9 hours. Seared the skin side in a hot skillet for about a minute. Sprinkled it with a little fleur de sel and it was very good. The texture was unlike any I've encountered before.

Tomorrows experiment is a brined cornish hen.

Brine: low fat milk and kosher salt. I've been brining in milk for about 5 years. Based on the results I get I think there's something about the lactic acid in the milk that makes the meat creamy.

Fat: when cooking via sous vide, putting fat in the bag makes the density outside the food higher than it is inside and the juices stay in. I'll make a fresh poultry seasoning using black pepper, nutmeg, and fresh thyme, sage, marjoram, rosemary and whip into some butter and evo.

Cooking: I'm going to aim for 12 hours at 160°F.

[nathanm]

Sounds like you are having fun.

One minor quibble - fat in the bag isn't going to help keep juices in because its density is actually lower than the juices. You can see this because if you pour off the juices and fat, (or stock and fat etc.) fat floats to the surface. Its density is lighter than water, or meat juices.

[johnder]

I am the proud new owner of an MGW Lauda MT Immersion Circulator Water Bath Heater on ebay for 70 bucks. :-)

Can't wait to try it out with these new recipes.

[Really Nice!]

Sounds like you are having fun. 

One minor quibble - fat in the bag isn't going to help keep juices in because its density is actually lower than the juices. You can see this because if you pour off the juices and fat, (or stock and fat etc.)  fat floats to the surface.  Its density is lighter than water, or meat juices.

You're right, fat floats. But somehow the fat does keep the juices in. See my post in this topic (number 130; fourth photo) as the butter has no meat juice in it even after four hours of cooking. And when I cut open the bag, there was not one drop of pink juice. When I did the duck breast, I did it without additional fat and there was about three tablespoons of juice in the bag when it was done.