Robert Jueneman

Sous Vide and the Smoking Gun Although I cook virtually all of my meat, and most vegetables (especially corn) sous vide, there is one thing missing from the outdoor BBQ, and that is the smoke-flavor that comes from a charcoal grill. Since I just received my new PolyScience "Smoking Gun," I thought it would be useful to try to add some smoke to a nice thick rib-eye we were having for dinner. The steak was cooked in my usual way, at 120F/50C for a couple of hours, then seared with a very hot Le Creuset panini grill and press to produce a cross-hatch pattern. I had previously spritzed the steak with a glucose solution plus some olive oil to enhance the Maillard reaction -- I don't oil the skillet and especially the top press, because it tends to flame too much if I have to heat it up again. Once the steaks were done, I covered them on a dinner plate with a large glass bowl, inverted, while I fired up the Smoking Gun. Then I inserted the tube under the bowl, and filled it with smoke from hickory chips. (In the process, I also imbued the kitchen, my clothes, and my face with some smoke, despite having the exhaust fan over the stove cranked up all the way, so maybe next time I'll do this on the porch, or outside.) The resulting overall taste and aroma was quite satisfying, and went well with the smoky Bloody Mary I had mixed earlier. I had had similar subtle but good results the previous evening with a smoky spinach salad, as per the PolyScience video. Compared to reviews of the Smoking Gun in eGullet from 2008-2009, this unit seems much improved. At least the bowl is no longer made out of wood, and although I haven't done it yet, it appears that the bowl and mesh should be relatively easy to clean. However, although perhaps I didn't use enough of the hickory chips and tamp it down firmly enough, I only got about 20-30 seconds of smoke, and had to fill it and light it again for the second steak. I've now learned to use a long candle lighter -- a cigarette lighter held upside down just gets too hot. But my main complaint is with the plastic stand that holds the gun. It is just light weight plastic, and several times I have had the unit fall over and dump smoldering particles on the kitchen counter. Not only is that annoying, it is also potentially dangerous. I'm going to have to see if I can find some thick metal, or perhaps a small but thick piece of ceramic tile, and glue it to the base to give it better stability. Three stars out of five, so far.

I agree with PedroG's points, but in addition I would suggest cooking your brisket for 72 hours. Bob

I've had my Thermomix for a couple of days now, and think I am going to really like it. So far, I've made the vegetable stock on page 17 of the cookbook (WAY, WAY too salty!), beef stroganoff (great!), chicken liver pate (not as solid as I would like, and I don't know what to do about it), and tonight it will be the mushroom risotto. The TMX recipe calls for 1100 g of water, but I think I will substitute store-bought chicken stock instead, and I probably won't use the vegetable stock -- or only a little. I may add some fresh tomatoes and basil, and perhaps some olives. For the last four or five years, I've cooked nearly everything sous vide, just because I don't have time to waste stirring the pot. But with the Thermomix to do that for me, things may change for the better! I really like the idea of drilling a whole in the spatula, so as to allow inserting an external thermometer for a more accurate temperature reading. Once you get used to demanding better than 0.5C accuracy for sous vide, it's a hard habit to break. The first step will be to calibrate the device to see how accurate it is, and then we'll see if any adjustments are possible. Has anyone had any experience using the Thermomix at high altitude? I'm at 7000 ft. (2133 m), so there is no way that water will reach 100C. What effect that will have on the Verona, and whether recipes need to be adjusted accordingly, I haven't any idea. Bob

This post, and in particular the "Culinary Biophysics: on the Nature of the 6XC Egg" paper that it references, has to be one of the most significant papers since Douglas Baldwin's Practical Guide to Sous Vide first appeared. It directly contradicts both Modernist Cuisine and Douglas Baldwin and what other most practitioners of sous vide have believed and taught, myself included. At least when it comes to an egg, both time and temperature matter, and matter greatly. Thanks, Smokalicious. You get my nomination for the best eGullet post of the year, so far. Great find.

Beef Cheeks - Mix together dijon mustard, chopped herbs (thyme, rosemary, dill), 1/2 crushed garlic and some cream of horseradish p. Slaver over the cheeks, place cheeks in vac pac add 1 jelly stock cube and 1 ice cube (or add 2 cubes your own frozen stock). Vac pack cook 60C for 72 hours. To finish remove cheeks and place liquid in a pan, bring to boil, strain, reduce liquid and use to make a sauce. I make batches of 6 of these and then either keep them in the cold temp draw in my fridge so I can have a great meal v quickly or freeze which only adds an extra 30mins to the reheat. My favorites are rib-eye, chuck, and brisket. Rib-eye is cook at 122F/51C for a time that is dependent upon the thickness and initial temperature (fridge or freezer), per Douglas Baldwin's tables, then post-seared using a very hot Le Creuset grill pan and a Le Creuset Panini press. Chuck is cooked at 131F/55C for 24 hours. An alternative is to cook it at 120F/50C for four hours to get the maximum enzymatic tenderizing effect consistent with food safety, then increase the temperature to 131F/55C. Post-searing as per the above. (Note to Fresh Meals Solutions, PolyScience, and others -- it sure would be nice to have a way to program this automatically!) ° Brisket is cooked at 131F/55C for 72 hours, then pan-seared and accompanied with your choice of BBQ sauce. I tried beef cheeks once, but was put off by a off smell that may have been caused by lactic acid -- maybe the meat wasn't a good as it should have been. I suspect those cuts don't turn over all quickly. Maybe I'll have to try them again, based ermintrude's recommendation. SV veggies remain under-explored, but to my taste, corn on the cob is much better at 140F/60C for 30 minutes, as recommended by nathanm, than the 185F for a hour approach recommended by some.

Geratherm Basal Thermometer (mercury free) Also referred to as an ovulation thermometer Manufacturer: Geratherm (Germany) URL: http://www.geratherm.com/en/ Price: $12.29 from Amazon Resolution: Markings at 0.1°F, to 0.02°F by visual interpolation Accuracy: No specific claims, but my unit agreed with my Traceable 4000 reference thermometer as closely as I could read it -- 0.02°F. Range: 96.1°F to 100.9°F Probe type: Clinical thermometer. Must be shaken down before use. Comments: Padded plastic case, with built-in magnifier. By far the most accurate thermometer for the money I have ever found. Well suited as a backup for a calibrated reference thermometer. Buy two at that price, and compare them.

TRACEABLE Control Company Model: 4000 Manufacturer: Control Company URL: http://www.control3.com/4000p.htm Price: $378.88 US Resolution: 0.001 degrees Accuracy: ±0.05°C between 0 and 100°C Range-50.000 to 150.000°C, -58.000 to 302.000°F Probe type: Various available, see URL. Traceable to NIST reference, calibration certificate included. Data logging capability available. Min/max and average readouts. 50 reading memory. Padded carrying case, AC Adaptor available Comments: I've been extremely pleased with this unit, and consider something at this level to be indispensable for a serious sous vide enthusiast, and certainly for a professional chef. My calibration expired 7/30/2010 -- I need to send it in for recalibration

Post -searing techniques I recently bought a Le Creuset grill pan and Panini press that has significantly improved my post-searing method for steaks, etc. I used to use a flat cast-iron pan, heated to the point of smoking, then toss in the blotted-dry steak and sear the top with a MAPP torch while the bottom was searing in the pan, then flip it over to get some additional juice on both sides. This technique worked reasonably well, although the torch tends to cause little black bumps, rather than a nice sear. But even if I SV'ed the steak at 120F/50C, this technique seemed to cook the entire steak too much, unless I went with a very thick steak (over 50mm). But with the Le Creuset combination, I can put both the grill pan and the cast iron press on the gas stove (on two different burners), so both get nice and hot, then sear both the top and bottom simultaneously. Then flip the steak and rotate it 90 degrees, then reapply the press for a perfect criss-cross grill mark pattern. (I should note that the instructions state than this cannot be used on a smooth glass-top cooking range, as the ridges of the press won't get hot enough. And I don't know about an induction range.) Spritzing the meat with a high smoke point oil (not olive oil) is an option, as is applying a brush of 5% glucose solution to enhance the Maillard reaction. I would avoid spraying the Panini press, so that it doesn't flame if you decide to reheat it, e.g, if you are cooking more than one steak. With this technique, not only did the steak look absolutely gorgeous, but the searing was a nice 1mm thick, and the interior of the steak even a bit too much on the rare side, at least for my wife's taste. I may do the next one at 122F/51C. And of course the combination can also be used for making Panini sandwiches. Bob

Pre-freezing the burgers seems like the way to go. But other than the fact that I don't happen to have small blocks of dry ice just lying around in my kitchen, I have some possible concerns about using CO2. My understanding is that it is used commercially to provide extended shelf life for say, chicken, under retail display conditions (not long-term storage). But doesn't CO2 plus water form carbonic acid (it's been a long, long time since my last chemistry class)? And although that might have beneficial bacteriostatic properties, do I really want carbonic acid on my burgers? If I do go the route of adding a gas port to my Minipack chamber vacuum, I'm thinking that I would probably want to use nitrogen, rather than C02 as the filler gas. Nathanm, you've got every appliance known to man -- do you have any thoughts on this issue?

I think this makes perfect sense from a theoretical perspective. A hamburger should be loosely held together when carefully formed and has air pockets between the strands of meat. Put it under vacuum and you make a sense puck out of it that won't crumble the same way a loose patty will. I'm sure the myocin protein has something to do with that as well. There is more meat to meat contact so the protein binds more of the meat strands together. My guess is: what Jason said. I can't confirm with double-blind anything, but if you had had the burgers I sealed to 99% using my spiffy new chamber sealer, well, you'd have no need for blindfolds. Same meat, same patty formations, same temps, same time: the four additional burgers I made using the Ziplok method were perfect (yes, best burgers ever, all that), whereas the four that were chamber sealed literally bounced when I dropped them on the counter. Interesting. And more from Kenji Lopez-Alt, talking about the Heston Blumenthal In Search of Perfection Hamburger, at http://aht.seriouseats.com/archives/2008/05/the-blumenburger-the-most-laborintensive-hamburger-in-the-world.html: "And finally, as for the meat: When meat is ground and salted, the salt and the mechanical action of grinding will cause some of the proteins in the meat (myosin, in particular) to denature and eventual link up with each other. The more you 'mush' the meat together, the more tangled up the myosin strands get, and the denser and rubbier your patty becomes. When you put meat through the small plate of a meat grinder, the long fibrils in the meat get cut into pieces that are at most the width and length of the plate (which in this case is 3mm) - small enough that it's not going to cause a sensation of toughness. What will cause toughness, however, is the relinking of myosin proteins after the meat has been ground. "That's why most good hamburger recipes where tenderness and open texture are key advise you to touch the meat as little as possible after grinding. What Heston is playing off of in his recipe is the fact that when meat is forced through the holes on the plate of a meat grinder, those myosin proteins are linking up with each other into long strands - strands which are tougher to bite through widthwise than they are to separate from each other lengthwise. "It's an interesting idea, but I don't think it really worked. I make burgers in which I nearly freeze the meat before grinding (cold proteins are less likely to denature and link up), and I think the burgers I get using that method are more tender than these ones were, even without the 'pain in the ass' aligning of ground meat strands." So nearly freezing the burgers before sealing them seems like a good idea, as does minimal compression and handling, and doing everything with meat that you grind yourself (preferably a mix of chuck, brisket, and dry-aged short ribs, if you can find them). Unfortunately, this sort of goes against one of my objectives, which would be to be able to pre-package such burgers and freeze them, rather than have to go through all of this when I'm in a hurry for dinner. And certainly freezing burgers in a Ziploc bag is going to produce freezer burn in relatively short order, and undesirable oxidation as well. Setting the chamber vacuum to a lower percentage, or stopping the FoodSaver when you start to see some compression would presumably help, but another alternative might be to use a Modified Atmosphere Packaging technique (for those with a really, really, really spiffy chamber vacuum -- one with a gas port), in which case you could suck out all of the oxygen and then introduce whatever amount of CO2 or nitrogen into the bag you choose (maybe 10-20%?) to avoid the compression factor. Of course the bags might then float, and might not get perfect contact with the water, but ... Or you could say forget about a burger, and just eat the chuck or brisket, etc., as a steak instead. Much simpler!

I think this makes perfect sense from a theoretical perspective. A hamburger should be loosely held together when carefully formed and has air pockets between the strands of meat. Put it under vacuum and you make a sense puck out of it that won't crumble the same way a loose patty will. I'm sure the myocin protein has something to do with that as well. There is more meat to meat contact so the protein binds more of the meat strands together. Kenji Lopez-Alt also uses the Ziplock technique, FWIW. Cf. http://www.seriouseats.com/recipes/2010/06/sous-vide-burgers-recipe.html On the other hand, there is an interesting post at http://www.fiftyfourdegrees.com/lang/en-us/archives/370, wherein he was careful to chill the burger before sealing it, so that it would hold its shape. If the patty is nearly frozen before being sealed, it would seem that the "hockey puck" compression effect would be minimized. Now, whether that would minimize the "rubbery" texture Chris talks about, I don't yet know. Yet another variable to consider. Finally, see http://blog.ideasinfood.com/ideas_in_food/2010/06/the-meat-grinder.html for a discussion about freshly ground beef vs. beef that has oxidized in the refrigerator overnight. Hey guys, this isn't Neanderthal-style cooking we're talking about here - this is about physics, and chemistry, even if it's in a beer cooler! Bob

The proper vacuum setting for various kinds of SV cooking is certainly one of the more contentious issues around, ranging from "just suck the air out of a Ziploc with a straw" to "use a chamber vacuum set at 99.9% plus 30 seconds for everything." Some people say that fish turns mushy under a hard vacuum, and others saying that fish normally experience much higher pressures when swimming than atmospheric pressure could possibly induce, and so this doesn't make any sense. The problem becomes even more complex when you consider the optimum conditions for long-term frozen storage, vs. simply cooking a meal, at least for those of us who would like to take a pre-sealed bag out of the freezer and throw it in the water bath, without having to mess with it again. Blackp and I tried to replicate Dave Arnold's finding that a hard vacuum causes dryness, but were unable to confirm the effect -- at least with chicken. And at least with my chicken tenders, the hard vacuum lost 2% LESS in turns of meat juices than the softer vacuum versions. Go figure. As I say, I don't cook hamburgers SV that often, and so I can neither confirm nor deny Chris' claim that a harder vacuum makes the hamburger rubbery. But I would like to see some double-blind tests done, before this bit of possible folklore gets enshrined. Maybe his results were due to a particular grind, etc., or maybe he discovered a Higgs boson, or whatever, but so far I don't understand the food science behind rubbery hamburgers and a hard vacuum. Can anyone else confirm or deny this?

I don't eat a lot of hamburger, but I have prepared them SV, and would certainly do so for anyone who might be immune compromised, pregnant, etc. Form nice big thick 1" patties however you'd like, including seasoning, onions, etc. SV them at 131F/55C for two hours to pasteurize them. Then post-sear on a very hot grill, or in a cast iron skillet that is smoking hot, to get the Maillard reaction and the outer char, while still keeping the inside a nice medium rare. If you aren't concerned about pasteurization, then SV them for a couple of hours at 125F/50C , and then sear as above for a deliciously rare interior. Sure beats all that crazy flipping, constantly watching, never quite knowing the right temperature on the grill, etc. And if you are cooking for a crowd, or on a picnic, it's even easier -- just package the pre-seasoned hamburgers four to a gallon FoodSaver bag, fill up a beer cooler with hot water, throw the bag in the hot water and drive off. When you get there, fire up the portable grill, throw the burgers on the grill and/or fan them with a torch, and pass the ketchup and mustard! If you have two coolers, fill one with hotter water (150F), bag up some corn on the cob with butter, lime juice, and chipotle, and throw those in the hot water for 30 minutes. Char briefly on the grill later, if you like. And if you have three coolers -- well, it is a BEER cooler, isn't it? :-)

This has been a fascinating and very enlightening thread, and I'd like to summarize what I've taken from it, vis a vis the food safety issues: 1. Pasteurizing beef at 131F/55C or higher kills (and keeps killing) all of the vegetative pathogens, so cooking/holding meat at that temperature is safe, virtually forever, although you don't want to overdo it, especially with cuts that are relatively tender to begin with. (We are primarily talking about beef here, and not poultry, and certainly not fish.) 2. Pasteurization does NOT kill the spores of certain harmful bacteria, such as C bot. So reducing the temperature after pasteurization to below 55C would allow those spores to germinate relatively rapidly. In the process, and especially in an anaerobic environment, potentially deadly neurotoxins could be produced. 3. Re-pasteurization at the end of such a process would again kill off any of the bacteria that had germinated from the spores. 4. Fortunately, those same neurotoxins (at least those from C. bot.) are broken down by heat, achieving an 8D reduction after 2 hours at 55C. So IF you re-pasteurized completely, as with Kenneth's pastrami-left-in-the-sink case, you are most likely safe, even disregarding things like nitrates, salt, and pH. However, this is a pretty tortuous and convoluted argument, and I would hate to think that we had overlooked something in the process. So I can't recommend that approach. 5. In any case, just because it doesn't kill you doesn't mean that the end result is going to taste or smell good. In particular, lactic acid build-up may not be harmful, but I wouldn't want to eat the results. Other possible decomposition (AKA spoilage) by-products could also exist. 6. The reason for proposing this not-very-well-thought-out violation of the standard cook-chill rules was an attempt to SV a relatively tough cut of meat, such as chuck, to make it as tender a possible, while still maintaining a rare degree of doneness. But it appears that the enzymes which help to age and thereby tenderize beef muscle operate at their maximum efficiency at around 120F/48C, and slowly become denatured at higher temperatures, thereby ceasing to be effective any more. So pasteurizing first, and then holding the meat at a lower temperature, as I had proposed, wouldn't do any good from a tenderizing perspective, over and above the complex food safety issues. 7. However, doing it the other way around, with a multi-stage heating approach as suggested in MC, does seem to make sense. The idea here is to SV the meat at around 120F/48C for four hours to promote maximum enzymatic action, and then to increase the temperature to 131F/55C and cook it for as long as seems necessary -- probably 20-24 hours in the case of chuck, or even 48-72 hours for brisket or short ribs, in order to slowly convert the collagen into gelatin -- a process that is primarily controlled by heat and time. 8. If for some reason the meat is not consumed immediately afterwards, either because you were preparing for later reheating, or because there were leftovers, the standard ice-bath discipline should be used to lower the temperature as quickly as possible, to below 4C. This is particularly important in the case of food that has not be exposed to oxygen, because C. bot is an anaerobic bacterium, and can germinate and produce neurotoxins while still sealed in the bag, unless the temperature is reduced to the point where their multiple rate becomes negligible. Did I miss anything?

I'm increasingly glad I threw out my experiment! But Douglas, maybe you can enlighten me. How can the spores of these bacteria be destroyed, BEFORE cooking/pasteurizing? In particular, considering pre-searing vs. blanching, would one method be better than another? (Seems to me a thorough pre-sear with a torch or a hot oil filled pan would be best -- it will get a lot hotter than blanching.) Likewise, suppose that some spores HAVE germinated -- the primary threat is the neurotoxins, right? How can they be neutralized/destroyed? I am assuming that the meat has not been Jaccarded or otherwise punctured, so (presumably) the interior of the meat is still sterile, and all we need to worry about is what might be on the surface. True? Bob

I did the same thing with six nice rib-eye's -- bagged them up with the chamber vacuum, then left them sitting on the counter! Repasteurization MIGHT be safe, but I would first open the package and smell it. You might have lactic acid build up, which although relatively benign, won't taste or smell very good. I'd say it was time to head for the local deli. Bob

You mean you violated the cook-chill recommendation for meat that isn't pasteurized correct? Because you were going to keep it at 120? If you brought it up to 131 for pasteurization time the 6 hour total no longer applies, right? Just want to make sure i'm understanding. Well, let's think about that. Because I was proposing that the meat be pasteurized initially, it's true that the 6 hour rule no longer applies, and I could hold it at the same pasteurization temperature until it completely falls apart. But I neglected to adequately consider the fact that pasteurization doesn't kill spores, which could then still germinate in that nice 120F Petri dish, and that that temperature is presumably NOT high enough to assure on-going pasteurization. How long it would take for a dangerous level of neurotoxins to develop, and how dangerous it might be, I'll leave up to someone who is a far better microbiologist than I'll ever be. I don't need Botox, either on the inside or the outside of me! Bob

Kenneth, just to make absolutely sure that I don't kill someone, please read my response to e-monster, above, and DON'T DO WHAT I WAS SUGGESTING IN MY EXPERIMENT! Bob

Hi Bob, I believe that you are mistaken in thinking that the issue of spores is only relevant to long-term storage under anaerobic conditions. There are both aerobic and anaerobic pathogens that you need to worry about. And you are talking about holding the spores in a growing medium for an extended period of time in the danger zone. To me, that sounds like an opportunity to incubate the spores and have them start growing. Keeping the meat in the high end of the danger zone is more likely to result in growing the spores and having the resulting bacteria multiply than storing unsterile but pasteurized meat for long times in the refrigerator where the multiplication rate is retarded by the temperature. Perhaps, I am mistaken. But I wouldn't risk it without hearing from someone with real expertise because if you are wrong, you could end up being very sorry. Best, Edward Edward, the more I think about it, the more I'm afraid you may have an excellent point, and may have saved me from an unpleasant experience. Basically, and without really thinking it through carefully, I was proposing to violate the cook-chill recommendations, whereby food should either be cooked and promptly eaten (still hot), or rapidly chilled (no more than 6 hours total, from cold to cooked to cold again) to below the germination point of the spores, or around 4C. As I understand it, spore production during the cooking cycle is not much of a concern, assuming the meat is being held within the pasteurization zone -- if a spore does germinate, the result would quickly be killed. (I'm not entirely clear on what happens to any neurotoxins in that case, but my understanding is that spore germination is a process that takes days, and not hours.) But in my experiment, although the meat would have been pasteurized initially, the spores would not have been destroyed, and they might then germinate and recontaminate the meat. Even thoroughly searing the meat (or reheating it back to 131F) prior to service wouldn't necessarily make it safe again, especially if any neurotoxins have already formed, since pasteurization does nothing to such toxins. (Whether searing would destroy such toxins I don't know (I suspect it would), but it would be difficult to sear the entire steak, including the edges, sufficiently well to be sure everything was safe. And I've got enough problems right now recovering from pneumonia without adding botulism to the list! So the conclusion is, DON'T EVER DO WHAT I SUGGESTED, PEOPLE! I'm going to toss out the meat that's been incubating overnight at 120F, and enjoy the 131F chuck for dinner. Thanks again for your concern.

Bob, Pasteurization only kills the living bacteria, it does not kill spores. So, pasteurizing the meat and then holding the meat at 120F sounds iffy to me. I think you would need to sterilize (rather than pasteurize) the outer surface. Killing the spores requires high temperature--so you would need to do that with a torch and be confident that you don't have spores in the bag, etc. If you search the old thread (it is probably in the index), you will find an extensive discussion in which Nathan and Douglas discuss the various methods by which meat becomes tender. As mentioned above, the enyzmatic process by which meat becomes tender is a completely different process than the breakdown of the collagen. They discuss the various temperatures at which these things happen and how temperature comes into play. My understanding is that the length of time needed to pasteurize the meat is probably long enough to denature the enzymes. The time that it takes collagen to break down at 120F may be many times what it takes at 131F. That's my take anyway. Best, Edward Edward, thanks for the comments. I do indeed understand the difference between pasteurization and sterilization with respect to killing spores, and not just bacteria, but to the best of my understanding, this is not likely to be a problem for meat that is being cooked and not stored for long times, e.g, under anaerobic conditions and not frozen. I guess I will have to go back and review the old threads with respect to meat tenderization, specifically with regard to the denaturation of enzymes, or read/reread that section of MC. But by tomorrow night I should have a practical answer as well, and hopefully it won't kill me! Bob

Jason, This doesn't specifically address safety, but in MC, page 2-274, "MAPP gas or oxyacetylene torches work better than propane or butane for producing high temperatures and no gas flavor" HTH, Larry Right, but they don't discuss MAP/Pro which is the MAPP replacement which is discontinued, and i find it kind of curious that they don't even in passing mention that it's food safe blah blah blah. I'm just wondering if anyone has any reference to feel that it's safe or not. See http://en.wikipedia.org/wiki/MAPP_gas, and the Material Data Safety Sheet at http://www.bernzomatic.com/Portals/8/Resources/msdsSheets/eng-Mapp_Gas_MSDS_2008.pdf. The gas is stated as having an unpleasant garlic/fishy odor at 100ppm (1/10 strength), and may be an asphyxiant, in addition to the liquid gas causing skin freezing. Oh, and the usual State of California cancer and birth defect warnings that apply to damn near everything, although the MDDS does not indicate any carcinogenicity. Personally, I have never smelled anything from my MAP/Pro torch, and the fact that it burns so hot means that I'm probably reducing the carcinogenicity of torching the meat. You could equally well worry about using canola oil, eating red meat in general, burning the house down, etc., all of which might be a higher risk. Now, if I were 50 years longer, and working in a restaurant and using it for 12 hours a day, day in and day out, I might worry a bit more, or change professions.

Kenneth, you may very well be right. However, it certainly isn't obvious to me, at least, that 131F will kill off all enzymatic activity, such that subsequent holding at 120F would then essentially do nothing. Do you believe that it is enzymes that converts collagen to gelatin? I though that was mostly just due to heat? I suppose enzymes must play a role, somehow, but I don't know at what point they would be come deactivated. But I doubt it is as low as 131F. I do understand that lowering the temperature after cooking meat for a relatively short while doesn't somehow "undo" the previous higher temperature, and make the meat go into reverse!. But on the other hand, it is not obvious that cooking something for say two hours at 131 followed by 48 hours at 120 is going to produce an identical result to holding the meat at 131 for the entire time. Certainly we know that as meat cooks, particularly at higher temperates (like in a braise), the muscle fibers contract and squeeze out the juice, and that is what causes an overdone piece of meat to become dry and tough. But it isn't obvious that this takes place instantaneously, such that once it's been subjected to 131F, that's it, and nothing more is ever going to happen. I therefore think that an experiment is in order. I happen to have a couple of pieces of chuck in the freezer, and sufficient SV apparatus to cook both simultaneously at two different temperatures, beginning later this afternoon for dinner tomorrow night. These are 30mm thick, so they will take 1:23 to come up to temperature, after which I will hold them for 90 minutes to pasteurize them throughout. I will then lower the temperature on one to 120F/50C, and keep the other at 131/55C, and taste the difference after 24 hours. Fair?

The issue here is tenderness vs. food safety. Chuck at 125 F for 48-72 hours would certainly be tender, but probably not safe. You can do anything you'd like if the food is not outside of the 4F-131F danger zone for more than four hours until it is eaten -- you can even eat it raw, like beef tartare. Unfortunately, the tougher cuts of meat, such as chuck or brisket, simply won't become tender at those low temperatures for such relatively short times. Instead, they take 24 to as much as 72 hours to turn the collagen sinews into gelatin. By cooking at 131F, you are effectively pasteurizing the beef, and thereby avoiding the potentially nasty bacteriological problems you might otherwise encounter. (I'm assuming here that you don't have access to a nuclear reactor or other way of irradiating your meat!) So you have a choice. If you like your steak really rare, buy a filet or a rib-eye, and cook it at 120F the way I do, and then post-sear briefly with a torch or a hot pan (I use both simultaneously). But if you want delicious flavor and reasonable tenderness at $2.50 a pound rather than $10+ a pound, try cooking a 70mm chuck steak for 24 hours at 131F, or a brisket for 72 hours. I think you'll be pleasantly surprised. It won't be blood-red, still-bawling rare, but it certainly won't be a gray medium, either. One more thing, and this is something that I haven't tried yet, but Modernist Cuisine talks about a two-stage cooking technique, where the meat might be cooked at 120F for up to four hours for flavor/tenderness, and then briefly heated to say 131F for the desired amount of doneness. I think it ought to be possible to reverse that approach, and heat the meat at 131F for just long enough to pasteurize it (see the tables in Douglas Baldwin's PDF), and then back off the heat to say 120 for as long as you'd like for tenderness. I don't know, and certainly can't guarantee, that this "backwards" approach would preserve the "rare" look and feel that you are looking for, but it might be worth a try, vs. cooking the meat for the whole time at 131F. Just a bit more on pre-searing and post-searing techniques. Many restaurants use a Jaccard to poke lots of tiny little holes in a steak before cooking it. By severing the meat fibers, it adds to the tenderness, and surprising, causes LESS juice to leak out, because the fibers don't contract as much. However, because of the strong possibility that the outside of the meat is contaminated, if you do use a Jaccard, you really ought to either pre-sear (very briefly -- maybe 15 seconds per side), or blanch the meat in boiling water for about the same amount of time, just to be sure. Also, I find that my Jaccard tends to compress the steak quite a bit, making them thinner than I would like (they then cook too fast when post-searing), so ask the butcher to cut them thicker than they usually do -- 60-70 mm is about right. (If Costco is Jaccarding their steaks before selling them, I would be very, very nervous, and would want to see their HAACP and how they are doing this.) With a nice thick steak, I can heat up a dry cast iron pan as high as my gas stove will go, throw in the steak, and while the bottom is cooking, hit the top of the steak with a MAP torch, then flip it briefly. Spritzing the surface before hand with a 4% corn syrup mixture (no high fructose syrup) will also help the Maillard reaction. This gives me about right tradeoff between having smoke and grease all over the kitchen (if I use something like grapeseed oil in the pan for even better browning), vs. the torch-only approach, which tends to burn the little bumps on the surface of the meat, but doesn't evenly brown the surface. If the steak is too thin, however, this double searing technique may overcook it, even if you SV at 120F. In that case you can compromise and use a cold cast iron pan and a torch, but in that case you might find that the steak is cold and underdone, depending on your taste. YMMV. And finally, adding the Scotch to the pan juices was a waste of good Scotch. It vaporized too quickly, make the whole kitchen smell like a distillery, and I couldn't taste any difference in the final result. Next time, I'll imbue the smokey flavor with the meat and the Scotch in my mouth!

I agree with Nick. I SV'ed a 60mm ribeye last night (enough for the two of us for two nights) at 50C, then seared it using a well-seasoned DRY cast iron pan that was preheated for about 10 minutes. I left the steak in the pan until smoke filled the room, but at least there was no significant grease spatter (I should have used a grease screen as well). Then I flipped it over, and did the other side, using the fat from the steak to intensify the Maillard reaction a bit. The combination formed a very nice crust without overcooking the meat, which however looked rather pink, rather than the reddish look I would prefer -- maybe due to the cut of meat? That was with a flat cast iron pan. Next time I'll try my ridged pan, to put some grill marks on it. Today I picked up six nice rib-eye's, and I want to prepare them a little differently that I usually do. I'm going to Jaccard them for a little extra tenderness, and then add maybe 5ml of Laphroig Scotch per steak to imbue them with a slightly smoky flavor. So the first question is, whether to scald the steaks quickly in boiling water (15 seconds) before Jaccarding them, or pre-sear them briefly with a torch or in a pan. I'm inclined to trim off some of the fat, render some of the fat in the pan at the same time using both the torch and hot pan method, then add the Scotch and set it ablaze briefly to cook off the alcohol (so that the vapor doesn't fill up the SV bag while cooking, preventing a close contact). I'll then pour some of that mix into each SV bag and chill it again in the fridge (standing upright) before vacuuming packing it with my chamber vacuum. I'll probably try some of the Sous Vide Supreme spice sheets at the same time, maybe the Southwest style, although that might go better with a little tequila and lime, rather than Scotch. I'll have to try several of them, on the different steaks. Based on several research reports I've read, it seems important to keep the oxygen level for storage below 0.1%, which would call for a vacuum setting of 99.5%. So far, at least, the concern about surface temperature boiling of the meat hasn't been confirmed, and in fact my tests with chicken saw very little change. And since I'm going to be cooking these at 50C rather than 63C, I don't expect to see any difference with this relatively hard vacuum. Then, once I've SV'ed the steak, I'll dry it, brush on a little Maillard-enhancing juice (4 g of corm syrup in 100 ml of water), and again sear it very briefly (so as not to overcook it) with the simultaneous hot pan and torch method. Any comments or improvement suggestions?

I recently repeated Peter's (blackp) experiment, with the same results. I purchased a tray of "chicken tenders" (cut from a chicken breast to a remarkably uniform size). I then weighed and cut each one to be as close to 50 grams as my scale would allow (+ or - one gram, or 2% accuracy). One was vacuum packed at 99.9% + 30 seconds. Another was vacuum packed at 99.9+30, then opened and repacked at 70%. A third was packed at 95%, and a fourth at 80%. All four were cooked SV for 2 hours at 63C, immediately afterwards. After cooking them, I opened and weighed each piece. Each weighed 46g, except for the one which was packed at 99.9% + 30 seconds, which weighed 44g. I didn't bother to photograph the pieces, because I couldn't detect any visible differences at all. As far as the organoleptic quality (taste, smell, visual appearance, mouth feel), I couldn't tell any significant difference. To the extent that there was any, the piece that was vacuum packed at 99.9+30 tasted somewhat less dry and more juicy than the others, despite the fact that it lost 2g more in juice! Go figure! My wife ate the remains of the test in an chicken sandwich, and liked it. I also cooked the rest of the package, put it in an ice bath until dinner, then grilled it on on my cast iron plancha and made a grilled chicken caesar salad with roasted caperberries. Quite good! As a result, I have to say that at least for very short vacuum times, there doesn't seem to be any significant difference between the different vacuum levels, and if anything, the higher vacuum settings seems to work as well or better, regardless of which way the water swirls going down the drain. Now, would things change if we packed the same chicken pieces in the same different vacuum levels, and then froze them for say a couple of months in that condition? TBD -- more research is required.