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Sous Vide: Recipes, Techniques & Equipment, 2011


Qwerty
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I suspect that you'll find that at least one of these developers has relied even more heavily on Douglas' tables than you. It is no accident that Douglas is studying for his PhD in applied mathematics, the calculations involved in creating the tables are somewhat complex.

Nick Reynolds, aka "nickrey"

"The Internet is full of false information." Plato
My eG Foodblog

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Hi Seth, welcome to eGullet and the sous vide community.

See my earlier comment on the new version of Douglas Baldwin's Practical Guide. Many other tables or apps may be based on the older version of Douglas' tables which did not yet take into account E.coli for pasteurization times.

Peter F. Gruber aka Pedro

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Thanks for your responses. Pedro, I have read through most of D. Baldwin's updated guide and certainly want to be sure to eliminate/minimize all the bugs possible, including E. Coli - think I'll stick with those numbers.

Thanks to everyone for all the recipes and photos - keep them coming!

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I've been having some trouble with my bagged items getting sucked towards the circulator and blocking the pump, so i decided to make a guard of sorts.

I have 1 question though. I got a decorative aluminum sheet made out of mill spec aluminum, apparently uncoated. Normally these sheets are used as decorative things on doors...i should be ok health wise right? I know we cook in aluminum pots, and i don't buy into the aluminum/Alzheimers connection...but want to make sure i'm not poisoning myself based on the aluminum grade or type.

got it at home depot. Cut it, and rolled it into a cylinder.

photo.JPG

Edited by jmolinari (log)
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What you've built is similar to the guard used on the PolyScience circulator (the big one).

You aren't cooking in the tank directly, so you could have made the guard out of lead, for all that it matters.

Bob

I figured the polyscience guard was made of stainless...no?

I do sometimes cook eggs, so i think i'll avoid the lead :)

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I've been having some trouble with my bagged items getting sucked towards the circulator and blocking the pump, so i decided to make a guard of sorts.

I have 1 question though. I got a decorative aluminum sheet made out of mill spec aluminum, apparently uncoated. Normally these sheets are used as decorative things on doors...i should be ok health wise right? I know we cook in aluminum pots, and i don't buy into the aluminum/Alzheimers connection...but want to make sure i'm not poisoning myself based on the aluminum grade or type.

got it at home depot. Cut it, and rolled it into a cylinder.

photo.JPG

Looks nice, no health concern, but with a bimetallic situation you might have corrosion problems, see upthread post #495 to post #513. Fortunately, if corrosion should happen, it would damage the aluminum sheet rather than the stainless steel circulator.

Peter F. Gruber aka Pedro

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What you've built is similar to the guard used on the PolyScience circulator (the big one).

You aren't cooking in the tank directly, so you could have made the guard out of lead, for all that it matters.

Bob

I figured the polyscience guard was made of stainless...no?

I do sometimes cook eggs, so i think i'll avoid the lead :)

Yes,I think the PolyScience guard is stainless steel.

However, if you are cooking eggs, I strongly recommend you follow PedroG's suggestion, and cook the eggs in a ZipLoc bag that is filled with hot water, rather than letting them bounce around loose. If one cracks and leaks albumin into the tank, you are going to have a very messy clean-up job.

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What you've built is similar to the guard used on the PolyScience circulator (the big one).

You aren't cooking in the tank directly, so you could have made the guard out of lead, for all that it matters.

Bob

I figured the polyscience guard was made of stainless...no?

I do sometimes cook eggs, so i think i'll avoid the lead :)

Yes,I think the PolyScience guard is stainless steel.

However, if you are cooking eggs, I strongly recommend you follow PedroG's suggestion, and cook the eggs in a ZipLoc bag that is filled with hot water, rather than letting them bounce around loose. If one cracks and leaks albumin into the tank, you are going to have a very messy clean-up job.

Good suggestion. When i do eggs i hang them in a basket/strainer on the side of the tank, but putting them in zip bag isn't hard

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Such a nice thread about Sous Vide. I'm reading a bit and thinking of trying it out for the first time. I hope I won't fail. Thanks for all the tips! ;)

Nothing wrong with failing... it's the best way to learn! Chances are everyone has failed at least a little bit, so don't feel bad if you do, and don't let it stop you from progressing - learn from the mistakes and be better for it!

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So here is what I have planned for the experiment... I want to lay it out before I do it to avoid being crucified for improper procedures ;)

1.) Purchase 2 packs of the pre-cooked ribs (vacuum sealed in plastic with barbecue sauce).

2.) Open each pack, cut off 1 rib from each and taste to ensure they are indeed fully cooked and TOUGH (as they always are straight out of the pack)

3.) Vacuum seal both, put one in the refrigerator and one in a 56c water bath.

4.) Cook the ribs SV for 72 hours, and for the last 1 hour, put the package that was in the refrigerator in the bath to bring it up to the same temp as the SV cooked pack.

5.) Taste and see if SVing a tough precooked piece or meat does or does not tenderise it.

?

Experiment complete.

What did I find out?

That the 72 hour SV ribs were indeed MORE TENDER, so much so that a blind test between the 2 was obvious in terms of texture.

I am not sure about the mechanism behind why this occurred, but it certainly did. I thought perhaps the water bath temperature had creeped up in certain areas, causing higher-heat induced tenderising (rather than lower-heat enzymatic) but after checking my dual temperature loggers, the temperature stayed between 55.7 and 56.8 in both areas of the water bath for the entire 72 hours.

For a little bit of fun, here are the 2 racks of ribs being dissected before being devoured for "scientific testing" :cool:

p.s. yes, that is House M.D. playing on the TV in the background ;)

Edited by infernooo (log)
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So here is what I have planned for the experiment... I want to lay it out before I do it to avoid being crucified for improper procedures ;)

1.) Purchase 2 packs of the pre-cooked ribs (vacuum sealed in plastic with barbecue sauce).

2.) Open each pack, cut off 1 rib from each and taste to ensure they are indeed fully cooked and TOUGH (as they always are straight out of the pack)

3.) Vacuum seal both, put one in the refrigerator and one in a 56c water bath.

4.) Cook the ribs SV for 72 hours, and for the last 1 hour, put the package that was in the refrigerator in the bath to bring it up to the same temp as the SV cooked pack.

5.) Taste and see if SVing a tough precooked piece or meat does or does not tenderise it.

?

Experiment complete.

What did I find out?

That the 72 hour SV ribs were indeed MORE TENDER, so much so that a blind test between the 2 was obvious in terms of texture.

I am not sure about the mechanism behind why this occurred, but it certainly did. I thought perhaps the water bath temperature had creeped up in certain areas, causing higher-heat induced tenderising (rather than lower-heat enzymatic) but after checking my dual temperature loggers, the temperature stayed between 55.7 and 56.8 in both areas of the water bath for the entire 72 hours.

For a little bit of fun, here are the 2 racks of ribs being dissected before being devoured for "scientific testing" ;)

It is my understanding that you get collagen converting to gelatin at these temperatures due to a simple heat-related chemical reaction. It happens much more slowly at these temps than at higher temps. But I believe that is what is going on -- just as with short ribs at 48 or 72 hours cooked in this temperature range.

Since your meat was well-done to start out with, you probably could have gotten the same texture by cooking them at a higher temperature for less time without sacrificing anything. In fact, I find that with baby back ribs 7 hours at 167F results in ribs that are possibly too tender.

Best,

E

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infernoo, thank you for reporting your interesting experiment.

Enzymatic tenderization has been exhaustively discussed in excellent posts by nathanm and Douglas Baldwin.

As e-monster says, in this experiment it must be thermal conversion of collagen to gelatin, and it makes sense that you get a tenderization with 56oC/72h similar to conventional cooking 80oC/12h.

The enzyme collagenase is reported to denature at 60oC; this means, above 60oC it must denature, but at temperatures below 60o it may denature but at a slower rate. So maybe our 55oC/24-72h cooking converts collagen to gelatin enzymatically (and thermally) during the first 6 or so hours, but collagenase activity decreases with time, and continued cooking will convert collagen to gelatin mainly thermally. When cooking at higher temperatures, undenatured collagen reaches shrinking temperature before being converted to gelatin, squeezing juices out of the muscle cells, resulting in dry yet falling-apart-tender meat.

Peter F. Gruber aka Pedro

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I almost forgot! Some photos from the preparation... one showing the pre-bought ribs:

http://i68.photobucket.com/albums/i36/infernooo/smoking/IMG_0286.jpg

The second of them straight out of the packet... I cut one rib off to show that they have been pre-cooked:

http://i68.photobucket.com/albums/i36/infernooo/smoking/IMG_0287.jpg

The final showing them sealed and ready for the water bath and one for the refrigerator:

http://i68.photobucket.com/albums/i36/infernooo/smoking/IMG_0288.jpg

Edited by infernooo (log)
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Boneless chuck short ribs, select vs choice.

I was looking over a business (special costco oriented towards food service rather than consumer) costco for meat to sous vide. They had select ($3.09/lb) and choice ($3.69/lb) boneless chuck short ribs. I'm assuming these are the short ribs that seem so popular for sous vide. I'm not really clear on the difference between select and choice meat given that I intend to cook it sous vide. The price difference isn't much but I ultimately chose the select as I could buy it in smaller quantities (4lb vacuum pack vs 10lb) and I'm still experimenting.

I lost about 20% trimming off the fat and split it into 2 bags. The are currently in a 130F bath and I'm intending to take them out at 2 days and 3 days.

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Boneless chuck short ribs, select vs choice.

I was looking over a business (special costco oriented towards food service rather than consumer) costco for meat to sous vide. They had select ($3.09/lb) and choice ($3.69/lb) boneless chuck short ribs. I'm assuming these are the short ribs that seem so popular for sous vide. I'm not really clear on the difference between select and choice meat given that I intend to cook it sous vide. The price difference isn't much but I ultimately chose the select as I could buy it in smaller quantities (4lb vacuum pack vs 10lb) and I'm still experimenting.

I lost about 20% trimming off the fat and split it into 2 bags. The are currently in a 130F bath and I'm intending to take them out at 2 days and 3 days.

Select is one grade lower than choice, with prime being the grade above choice. As you move up in grade there should be more marbling of the fat resulting in a more tender and flavorful cut, all else being equal.

Select is what you find in the typical supermarket, usually under a marketing name like rancher's reserve or master cut. If a market has choice beef then it will more than likely be labeled as such. Retail Costcos carry choice or higher grades.

Not sure which is best for sous vide, I've done both (for steak, not short ribs) and my experience has been varied. Sometimes you get a great steak from select, sometimes from choice. Sometimes both can be less than ideal.

Mark

My eG Food Blog

www.markiscooking.com

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I'm planning to cook/chill some chicken breasts to use for dinner later this week, and would really like to serve it with the skin browned/crisped in the oven (per the recipe in D. Baldwin's book). Any reason I couldn't pull the skins off, refrigerate (or even freeze) them, and crisp them up while the meat is re-warmed in the water bath a few days later?

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I have been cooking sous vide for about four years and just run into this problem. I cooked a 48 hour, 4 pound brisket at 132F (55C), iced it, and then froze it in the sealed bag. I later thawed it out and reheated it in the same bag to the same temperature long enough for a second pasteurization to occur. This was for a diner, but the people could not make it at the last moment. I then re-iced it and put it back into the freezer. Since the brisket cost about $60 and I would rather not throw it out. Aside from the possibility of losing the texture of the meat, will it be safe to reheat again?

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I have been cooking sous vide for about four years and just run into this problem. I cooked a 48 hour, 4 pound brisket at 132F (55C), iced it, and then froze it in the sealed bag. I later thawed it out and reheated it in the same bag to the same temperature long enough for a second pasteurization to occur. This was for a diner, but the people could not make it at the last moment. I then re-iced it and put it back into the freezer. Since the brisket cost about $60 and I would rather not throw it out. Aside from the possibility of losing the texture of the meat, will it be safe to reheat again?

If I understand you correctly, the meat has been sealed in the bag all of this time, correct? If so, then it should be perfectly safe. In fact, I don't think there was any need to pasteurize it the second time -- you could have just rewarmed it.

If anything, your reheating will be comparable to just cooking it for a longer time, and since I cook mine for 72 hours at 55C, I think you will find it even better.

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I have been cooking sous vide for about four years and just run into this problem. I cooked a 48 hour, 4 pound brisket at 132F (55C), iced it, and then froze it in the sealed bag. I later thawed it out and reheated it in the same bag to the same temperature long enough for a second pasteurization to occur. This was for a diner, but the people could not make it at the last moment. I then re-iced it and put it back into the freezer. Since the brisket cost about $60 and I would rather not throw it out. Aside from the possibility of losing the texture of the meat, will it be safe to reheat again?

If I understand you correctly, the meat has been sealed in the bag all of this time, correct? If so, then it should be perfectly safe. In fact, I don't think there was any need to pasteurize it the second time -- you could have just rewarmed it.

If anything, your reheating will be comparable to just cooking it for a longer time, and since I cook mine for 72 hours at 55C, I think you will find it even better.

Hi Bob,

Hopefully, Douglas or someone with greater expertise will chime in. I have been led to believe that repeated heating/cooling cycles may have some issues since pasteurization is not sterilization and leaves spores intact.

I don't know what the exact rules are, but I seem to recall a friend of mine who is a pro telling me that there is a limit to the number of 'safe' heating/refrigerating cycles to which you can subject pasteurized meat before it starts becoming risky. It seems reasonable to think that what Mikels wants to do would be safe, but I am not absolutely certain.

So, hopefully someone with some expertise will chime in.

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Since you asked me to chime in, I will.

Mikels did everything right. The rapid chilling reduces the risk of sporulation and freezing prevents any pathogens that are present from growing. As Bob pointed out, Mikels did not need to repasteurize but just reheat (or rethermalize, as some like to call it).

When might you have problems with heating-and-cooling repeatedly?

The biggest problem is texture degradation, partly from longer cooking times and partly from ice-crystals formation. Neither of these is a big concern with brisket but are an issue with tender meat such as steaks, chicken breasts, fish, etc.

The food safety question is more complicated, but just because it hasn't been very well studied and so I can only give you my (expert) opinion. Let's look at the risks at each step:

  1. You buy your raw food and it usually has millions of microorganisms on and in it — most of which are spoilage bacteria. To reduce the risk of the harmful pathogens from multiplying rapidly, you store your meat, fish, and poultry in a refrigerator (or in a freezer) and use it before its “best by” date.
  2. You vacuum-seal your raw food. Vacuum packaging doesn't reduce any of the microorganisms, so you must either return it to the refrigerator or freezer or (in most cases) begin cooking immediately in a temperature controlled water bath.
  3. You heat your vacuumized raw food in a temperature controlled water bath or steam oven. This stage is known as a “critical control point” in the food safety biz.

    1. As the food heats, microorganisms begin to multiply rapidly with most of them growing fastest between 30°C (85°F) and 50°C (120°F). If you're not heating to pasteurize, then minimizing the growth of these pathogens is a critical step. For example, fish cooked rare or medium-rare shouldn't spend more than about an hour between fridge and table.
    2. Once the temperature of the food exceeds about 52.3°C (126.1°F), then all the known food pathogens stop growing and begin to die. (Johnson et al. (1983) reported that Bacillus cereus could multiply at 131°F/55°C, but no one else has demonstrated growth at this temperature and so Clostridium perfringens is used instead.) Many recommend that the core of the food reach 54.4°C (130°F) within 6 hours (even me) to keep C. perfringens to less then 10 generations (or less than 2 hr 10 min between 35°C and 52°C as per Willardsen et al. (1977)), but this is not a critical control point: While C. perfringens does produce toxins, it only produces them while sporulating (and so isn't a concern when heating) and the toxin is easily destroyed by heating (since it's destroyed in only 10 min at 60°C); see, for instance, Chap. 24 of James M. Jay's Modern Food Microbiology, 6th ed. (2000). So, it's only the vegetative form of C. perfringens that's a hazard when heating and they're easily reduced to safe level when pasteurizing for Salmonella, Listeria, or E. coli. Therefore, heating to 54.4°C (130°F) within six hours is only a critical control point if the food isn't then being pasteurized and the growth of other pathogens is often a greater concern. However, at some point the growth and toxin formation of S. aureus, C. botulinum, and B. cereus does become a critical control point since these toxins aren't destroyed when pasteurizing for active (vegetative) pathogens.
    3. If pasteurizing, then you hold the food at 52.3°C (126.1°F) or above until any active (or vegetative) pathogens have been reduced to a safe level. What's a safe level? That's a surprisingly tricky question. First, we don't really know how many vegetative pathogens will make you sick; about 15–20% of the US and UK population is more susceptible to foodborne disease (Lund and O'Brien 2011). Moreover, without knowing how many pathogens are present in the raw food or after heating, then we don't know how many we need to reduce even if we knew what a safe level is. (For an interesting discussion on this, I highly recommend “Scientific Criteria to Ensure Safe Food” from the National Academies Press (2003).) Therefore, we make an informed guess that a million to one reduction in Listeria monocytogenes, a ten million to one reduction in the Salmonella species, and a hundred thousand to one reduction in E. coli will be sufficient. You can, of course, see my guide for computed times for different thicknesses of food and for different cooking temperatures.
    4. If you eat the cooked food immediately, you don't have to worry about any additional pathogens growing.
    5. If you chill the food for later use — as I frequently do — then it's important to follow a few simple steps:
      1. You have to chill the food rapidly to limit sporulation of C. perfringens (since it creates its toxins while sporulating); we usually do this in an ice-water bath (see my guide for cooling times).
      2. You must leave it in its vacuumized pouch to prevent recontamination.
      3. You need to properly store the food in either a refrigerator (see my guide for times at different temperatures) or in a freezer: proper storage is critical in preventing spores of C. botulinum and B. cereus from outgrowing and producing toxins, which aren't destroyed when reheating (neither S. aureus nor B. cereus toxins are destroyed by heating and C. botulinum toxins need either a high temperature or a very long time).

[*]When you reheat (or rethermalize) your chilled food, your main concerns are the toxin formation of C. botulinum and B. cereus since you should have already reduced the non-spore forming pathogens in step 3. Reheating to a core temperature of 54.4°C (130°F) within 6 hours should be sufficient.

[*]Now, suppose you want to repeat steps 3 & 5. If you germinate and then kill C. perfringens, C. botulinum, and B. cereus over and over, you'll eventually destroy all the spore-forming bacteria (see sauce sterilization using Tyndallization for more information), but I don't know if you'll destroy all of them before a dangerous level of toxins has accumulated. I think you'd be safe if you cook-chill-reheat-chill-reheat-serve but I'm not comfortable recommending more than two reheat-chill cycles before serving. Further research is clearly required for a definitive answer.

My Guide: A Practical Guide to Sous Vide Cooking, which Harold McGee described as "a wonderful contribution."

My Book: Sous Vide for the Home Cook US EU/UK

My YouTube channel — a new work in progress.

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Excellent summary, Douglas. Thanks.

Now,let me ask a similar question about making stock.

I made some chicken broth by cooking 4 lb of chicken legs and thighs together with 8 oz of store-bought stock, for 12 hours at 70C, then drained it. Obviously that was well and throughly pasteurized, but not sterilized. I made chicken salad with the leftover meat.

Unfortunately, last night after adding the methylcellulose to fine it, I got distracted and forgot to refrigerate it then, but I did this morning. So it sat at room temperature for 8 hours or so.

Is there any safe way to reheat and use this, even by pressure cooking it, or should I dump it?

I'm inclined to dump it.

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