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Sous Vide: Recipes, Techniques & Equipment (Part 5)


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Posted
In light of recent posts, I'd better write this up just in case tonight's dinner kills me!

To start with - given the international conspiracy to call all meat parts by different names I have no idea what I cooked and ate tonight in terms familiar to the majority of the forum readers.  Regrettably I took no photographs so the best I can do is try to describe the cut as it was when bought from the butcher:

I cooked what I may call 'beef short ribs", but given some descriptions I'm not sure we're all talking about the same bit of cow/steer.

Assuming that the strips of meat were sitting on their rib side they were about 12 inches long, 2 inches wide and a varying amount high (from about 1" to 2.5").  They were cut across the ribs and there was about 7 or 8 bone pieces per chunk of meat.

(Note deference to US folk who can't yet understand metric measures which we moved to about 40 years ago!)

Hope that makes some sense - if it does can somebody tell me what that is called in USA terms? (Many of my cookbooks call for things I can't even find definitive descriptions for on the net!)

I cut each of the pieces into 2 (between the bones) bagged and vacuumed them separately after tossing them around in a bowl with EVOO, sea salt (maybe the same as Kosher salt - but here in Australia we have very few Rabbis to prove it!) and black pepper.

Next was to put them into the Tiger/SVM contraption at 56C and leave them there for 48 hours.

I have cooked this cut of meat before and the only way to make it good (despite it's good flavour) is to braise it with lots of other ingredients for several hours.

Having no idea what to do with potentially tender rib meat I decided to do nothing complex so that I could taste the outcome of the first experiment.

I baked some potatoes, onions and pumpkin in large chunks for about 1 hour at 180C (350F).

When the vegetables were nearly done - I removed the ribs from the bath and seared them with a blow torch.

I then added them to the roasting pan and turned on the fan-force and roasted them with the vegetables for about 5 minutes.

Net result - amazing!

The flavour was similar to the complex taste you only normally get from a tough cut of meat, but the texture was about as good as a rib-eye or fillet steak!

SWMBO was impressed!  (For those who've never seen "Rumpole of the Bailey", SWMBO means: "She Who Must Be Obeyed").

BTW - SWMBO takes some impressing - I already have an order to do this again - even though I've not begun to attempt any elaborate recipes based on the technique.

Now I'm after hints as to how to "dress-up" such a dish....

Cheers,

PB

If you like asian flavor, I suggest adding a slice of ginger and a little diced green onion plus a tablespoonful of Hoisin sauce (available in asian market and readily availbale in US super market). After SV, remove liquid from your bag and filter with paper towel or coffee filter to get rib of the protein so if you want to reduce the sauce you can without the scum. You can also thicken the sauce with a litter butter and flour. I think you will impress your SWMBO.

Posted (edited)
I cooked what I may call 'beef short ribs", but given some descriptions I'm not sure we're all talking about the same bit of cow/steer.

Assuming that the strips of meat were sitting on their rib side they were about 12 inches long, 2 inches wide and a varying amount high (from about 1" to 2.5").  They were cut across the ribs and there was about 7 or 8 bone pieces per chunk of meat.

Coincidentally, Cooks Illustrated Summer Grilling issue (out of season for you, I realize) had a piece on 10-Minute Barbecued Ribs. It had an illustration and explanation of four different cuts of "short ribs" that was interesting, as I had never seen the type you described:

English style -- This common choice contains a single bone about 4 to 5 inches long. Look for ribs that have at least one inch of meat above the bone.

Flanken Style -- The meat has been cut across the ribs and contains 2 to 3 oval-shaped cross-sections fo bones. These ribs can be difficult to find in the supermarket.

Korean Style -- This authentic choice (sold only in Asian markets) requires no butchering. The same as flanken-style ribs, but cut much thinner, usually about 1/4 inch thick.

Boneless -- A good option that is available at some markets. Make sure they are at least 4 inches long and 1 inch thick.

From the description, I assume you had flanken-style ribs, but a much longer cut than was described.

The recipe used a marinade consisting of a roughly-chopped pear, 6 garlic cloves, 4 tsp fresh ginger, 1/2 cup soy sauce, 2 Tbsp toasted sesame oil, t Tbsp sugar, 1 Tbsp rice vinegar, and three scallions, sliced.

AVFOOL's recipe seems remarkably similar.

BTW, what is a "fan-force"? A ventilation fan, a convection oven, or what?

Edited by Robert Jueneman (log)
Posted (edited)
Well, I didn't see the part in Under Pressure where it says meat has to be cooked to 60C. It is very hard to believe that the book does say that because French Laundry and Per Se surely don't follow that rule.

Nathan, I found the quote on page 35, in the Safety section, where the "danger zone" concept is repeated. Just because it is in print doesn't make it correct, of course.

It would be very interesting to see what Per Se's HACCP document states. Does NYC consider such things public documents, and are they accessible on-line? I couldn't find anything with a quick Google search.

However, if he really believes and follows those temperatures, it may explain the temperatures listed in the book, which I tend to think are relatively high -- by 10F or more in many cases. Or perhaps the publisher's lawyers also served as editors?

I just received "Alinea" by Grant Achatz. His beef sous vide recipes range from 135 to 139F, but for as little as 30 minutes. Then again, most are for Wagyu beef, which hardly needs cooking at all to be exquisite.

Bob

Edited by Robert Jueneman (log)
Posted

Bob, I read Thomas Keller's advice you referred to just now.

The ribs I cooked for dinner last night were too much for 2 people so given I'd bagged them into small parcels I took those I was not going to serve and immediately plunged them into an ice bath. After about 15 minutes in there I dried the bags off and put them in the freezer.

If the advice referred to above is correct I should throw them out!

I remember reading something in this forum about botulism (I think written by Nathan) and the fact that the spores are not killed at SV temperatures and indeed thrive in the anaerobic atmosphere. I couldn't find again it just now.

What do folk think of the safety issue of chilling then freezing meat that was cooked at 56C for 48 hours? I'm sure that MikeTMD will tell me not to eat them, but I would appreciate a wider opinion.

Thanks,

Peter.

Posted

You are correct that the spores have not been destroyed --- the only way to destroy all the spores is to use an pressure cooker. You have, however, pasteurized the food --- that is, you have reduced all the vegetative pathogens (the pathogens which are alive) to a safe level. So long as you keep the food sealed in their pouches, they cannot be contaminated with additional vegetative pathogens. Thus, all you need to do to assure the safety of the sealed pouches of food is to prevent the spores from outgrowing and multiplying to dangerous levels. This is easily achieved by rapidly chilling the pouch in ice water and either freezing or storing at (i) below 36.5°F (2.5°C) for up to 90 days, (ii) below 38°F (3.3°C) for less than 31 days, (iii) below 41°F (5°C) for less than 10 days, or (iv) below 44.5°F (7°C) for less than 5 days. [Please see the safety section of my guide for more details and references to the appropriate scientific literature.]

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.

Posted

Peter, from my perspective as a non-microbiologist, once something is cooked, it ought to be relatively safe. However, if you are running a restaurant, you need to be more careful than you might be at home. Flesh-eating attorneys are a worse danger than bacteria, IMHO!

People have casually been throwing leftovers in the "ice-box" for the last 100 years or so, and using an ice bath and then freezing them is much better than that and about the best you can do, at least without a large bottle of liquid nitrogen or an anti-griddle. You are probably more likely to die of a lightening strike, or an airplane falling out of the sky. (Maybe that depends on where you live, however.)

I see that Douglas has also responded, but he is talking about a situation where the food is still sealed in the original bag.

Assuming that you haven't been coughing, sneezing, etc., all over the cooked food, I think you are quite safe.

To the best of my knowledge, botulism and other anaerobic bacteria multiply DESPITE the absence of air, and not BECAUSE of it, and it takes weeks for the spores or toxins to become dangerous, unless you do something really stupid. Someone please correct me if I am wrong.

Bob

Posted (edited)

Re the flat-iron steak question.

I watched the butcher cut the shoulder clod into three pieces, after trimming off the fat, so if there is any contamination it is surely incidental.

Yesterday I cut the flat-iron section into steaks myself, so the interior was presumably sterile.

I then Jaccarded each steak, and then froze them. Although I had cut the steaks to about 1-1/2", Jaccarding them compressed the meat to about 1" in thickness.

I cooked two small frozen flat-iron steaks for 24 hours at 131F, and served them tonight.

They were nicely medium rare, but not quite as tender as I would have hoped or expected, and nowhere near the falling apart, almost mushy quality of the Morton's pre-marinated Tri-Tip I cooked the night before for only 12 hours.

I poured off about a half a cup of meat juices, added a little wine and some flour to make a quick sauce. For reasons that I don't understand, the sauce was a rather unappetizing gray. another thing to work on.

I heated a cast-iron skillet to the point that I couldn't keep my hand four inches above the pan for more than a couple of seconds, and then threw the steaks in, after having blotted any liquid from the surface. (Somewhere I have an infrared thermometer, but I couldn't find it.)

Searing the steaks in that hot pan worked nicely -- maybe better than using a blow torch.

The resulting flavor was OK, but not outstanding, and the tenderness and mouth feel was nothing to write home about either. The steak tasted rather dry. Maybe I should have let the steak rest for 5 minutes or so before opening the package, in hopes it would absorb some of the juices again.

I threw another couple of frozen steaks in the rice cooker tonight, and I am going to cook them at the same temperature for 36 hours to see if that helps. And if that doesn't work, I'll keep going until it falls apart, or I die of gastroenteritis or something.

The shoulder clod cost about $3.50 per pound, compared to decent rib-eye steaks at anywhere from around $9/lb (CostCo on sale), to $14.50 (Whole Foods) to around $22 for prime or dry aged beef, or $29 for Wagyu (American Kobe).

So the price is right, if I can fix the tenderness and taste issues. So far, the taste is commensurate with the cost, and not what I was hoping for.

Edited by Robert Jueneman (log)
Posted

Thanks for the input Douglas (And Rob).

Given that the bags were still sealed (ie from raw to cooked), and that I chilled them prior to freezing I guess they should be pretty safe.

Not being a mathematician I'm having some difficulty in understanding the info in the Safety section of your guide.

There is a sliding scale ranging from 2.5C to 7C with a corresponding time line of up to 90 days to less than 5 days.

How should I interpret this information given my freezer is -20C? Will any of the spores still be "alive" at temperatures so low?

Thanks,

Peter.

Posted

You can safely hold the food at -20C indefinitely. Eventually (after many years), you will develop some freezer burn on the food (since a very small amount of gas is able to permeate the plastic), but it will still be perfectly safe to consume. My only recommendation is to label the bags with a permanent marker so you figure out later what type and cut of meat it is and how it was prepared.

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.

Posted

Hehe!

My advancing years are enough for me not to remember what I put in the freezer a few weeks ago, let alone several years before.

One thing I've adopted as a great adjunct to freezer storage (after the vacuum packaging machine) is a Brother QL570 label printer (You need a PC or Mac as it is a USB connected printer and not a stand alone device). The best media to use is the continuous 62mm wide tape which will cut off at the length you need.

When I freeze anything it is easy to make labels to accurately describe what is in the bag. I usually put on the label what the content is, where I bought it, the date I packed it and if I added anything else to the bag - what that was.

I find that the labels do not deteriorate in the freezer, and after cooking some Salmon portions in the Tiger/SVM contraption the other day I found that the labels did not deteriorate in the 50C water either.

The big advantage is that when you cut up a big piece of meat like a whole rump or scotch fillet (go figure what the US equivalents are) it is no problem to create the 10 or 20 labels you need. We all know if we are required to write them out we will leave a lot of detail out as the time taken to fully describe each package is longer than we want to spend.

As a result my freezer has well labelled packages in it with all the info necessary to decide what to do with the pack next.

Now I'm using SV more often - I will pack some main protein items with flavourings before I freeze them - so the ability to make more verbose labels easily becomes more important.

Hope this is useful to some.

Peter.

  • Like 1
Posted (edited)
Re the flat-iron steak question.

I watched the butcher cut the shoulder clod into three pieces, after trimming off the fat, so if there is any contamination it is surely incidental.

Yesterday I cut the flat-iron section into steaks myself, so the interior was presumably sterile.

I then Jaccarded each steak, and then froze them.  Although I had cut the steaks to about 1-1/2", Jaccarding them compressed the meat to about 1" in thickness.

I'm not sure why you are specifically pointing out the sterility of the cut, but after you jaccard that it goes to hell anyway as you are using many sharp little knives to push surface bacteria into the sterile interior anyway. Even though you cut it from a larger muscle so that exterior should be sterile, unless you sanitized your knives and did it in a clean room, I wouldn't count on it.

That being said, I jaccard things like pork and beef and cook to 121-131f regularly so i don't think its a problem. also you are not jaccarding that meat you are beating the crap out of it. I really don't think steak should compress by 33% when you jaccard it but thats just me....

Edited by NY_Amateur (log)
Sous Vide Or Not Sous Vide - My sous vide blog where I attempt to cook every recipe in Under Pressure.
Posted

In my opinion, if you Jaccard without pre-searing and only cook to 121-131, I think that you are taking a risk. There are some really nasty strains of e-coli that have developed in the last 20 years. While the likelihood may be somewhat low that you will get a piece of meat that has it -- enough people get sick each year from them that I think it is worth taking appropriate precautions. (Like searing before jaccarding). Contamination is not just restricted to supermarket mystery meat.

Posted

NY_Amateur and eMonster, I have walked down both sides of this issue, and depending on which way I toss the coin, I come to a different conclusion. Perhaps the issue is how paranoid I feel on any particular day.

The steaks were freshly cut from a larger piece of meat, and it was the fresh-cut sides that were Jaccarded, so those sides were presumably sterile until 30 seconds ago. (And it wasn't the blades that compressed the meat, but the bottom of the Jaccard -- I think the spring mechanism used for safety is too strong.)

The knife came out of my knife block, so it was clean but not sterile. The Jaccard had come out of the dishwasher with a sanitize cycle, but it had been exposed to the air, and the plastic cutting board had also gone though the dishwasher but been exposed to the air.

So the question is, how likely is that steel and hard plastic become contaminated with bacteria or a virus from the air in and around my kitchen? I can imagine that a few germs might land on that surface, but I don't think they are going to grow there.

If the bugs are on the Jaccard, as opposed to being on the surface of the meat, then searing the meat won't make any difference. Searing WOULD help if the knife was contaminated, however.

I guess if I were doing this professionally, and potentially exposing people to germs to which my wife and I might be immune, but not someone else, I might take more care to wipe down my knife with an alcohol pad or dip it in a disinfecting solution before each use.

I certainly wouldn't want my doctor doing surgery with this level of sterilization (or the lack thereof), but in that case the bugs might be entering my body directly.

Granted, this might be true of the meat as well. but eventually, the meat is going to go in my STOMACH, which has its own set of well-developed protective mechanisms developed over many millennia.

If I thought I had to wear a mask, and sterile gloves, and run all of my kitchen tools through an autoclave before cooking anything sous vide, I would probably revert back to my Cro Magnum heritage and just throw the meat on the grill and hope for the best!

I am willing to grind my own hamburger. I might be willing to even sear or briefly boil the meat before grinding it in a freshly sanitized meat grinder, but even that is bordering on a Howard Hughes level of paranoia, I believe.

According to http://www.cdc.gov/ncidod/eid/Vol5no5/mead.htm, the total of all food born illnesses in the year studied, including bacterial, parasitic, and viral, was estimated to be 38,629,641, with 1,809 deaths. Of all of the illnesses, five pathogens accounted for 72% of the deaths: Salmonella 31%), Listeria(28%), Toxoplasma (21%) Norwalk-like viruses (7%), Campylobacter (5%), and E coli O157:H7 (3%).

In all likelihood, some of these illnesses were caused by salmonella or E. coli infected spinach, lettuce, and other products that are not likely to be cooked sous vide at low temperatures, and not by infected knife blades. In particular, I don't think parasites are likely to be transmitted in my knife blade.

To put all this in perspective, the number of automobile related deaths in 2008 was 37,313, so you are about 20 times more likely to be killed driving to or from the grocery store than from eating any of the products purchased there!

Posted

right that's my view on it, I lead a very high risk lifestyle in general so the risk of a food borne ilness in food I consume at home is on the back burner for me. My comment was just to make sure you didnt assume it was sterile when it was not. If you know the risks then go for it. I semi-regularly eat undercooked pork and other fun things so I am definitely not saying you should be 100% safe especially when cooking for yourself.

If you are cooking professionally, then yes, you'd better know and follow all the rules, otherwise who cares (famous last words right?)

Sous Vide Or Not Sous Vide - My sous vide blog where I attempt to cook every recipe in Under Pressure.
Posted
Mike, that's fair enough.

Tonight we had some Tip-Tip (Morton's Chardonnay marinated) that was cooked for 12 hours.  Whereas my previous trials with 1.5 and 2.5 hours at 131F showed that the meat was still tough, 12 hours was perhaps too much -- the meat was almost falling-apart tender (perhaps because of the marinade), although my wife loved it.

If in fact 24 hours for flat-iron is too much, I will certainly report that fact.

As to the micro-biology aspects, I will wait for your references.

Bob

OK, I am back home, so please find the reference:

Sous-Vide: Garen Im Vakuum

Viktor Stampfer

2009 Matthaes Verlag GmbH, Stuttgart

ISBN-10: 3875150279

ISBN-13: 978-3875150278

"The correct temperature for cooking sous-vide"

Chapter by Bruno Goussault pp.14-15

Noteworthy, the author cites microbiological studies performed at CREA.

"It's not from my kitchen, it's from my heart"

Michael T.

***************************************

My flickr collection

Posted (edited)

I took a liberty to compare cooking times for Lamb Loin, as per several different sources:

Achatz: 20 minutes @ 57C / Core temp - not specified

Keller*: 35 minutes @ 60.5C / Core temp - not specified

Roca: 20 minutes @ 65C / Core temp - 60C

Stampfer: 25-30 minutes @ 66C / Core temp - 64C

(* - Keller suggests the time and temps for lamb saddle - loin and tenderloin connected by transglutaminase)

I chose Lamb Loin for this illustration primarily because all four authors described cooking that particular cut SV.

Should anyone be interested, I would be happy to illustrate suggested temps for tenderloin, and/or braised cuts.

I would like to point out that the sources quoted come from four different, professional and accomplished chefs, as such their recommendations, in my opinion should not be ignored.

Edited by MikeTMD (log)

"It's not from my kitchen, it's from my heart"

Michael T.

***************************************

My flickr collection

Posted

Mike,

I'm not sure I see the relevance of the times you posted to the question of cooking tough cuts of meat -- which is where this all started. You can't compare the cooking time of lamb loin to the cooking time of chuck steak -- they simply aren't comparable pieces of meat with comparable characteristics.

No one disputes that tender cuts only need to be cooked to bring the meat up to temp. So, these times are not really germane to the question of long cooking of tough cuts of meat.

Vis-a-vis flat-iron steaks. A friend of mine was talking to a butcher and apparently there is a way to butcher them that removes most of the connective tissue during butchering which yields a tender steak. So, if one's source does this, it might be a tender cut of meat. But a lot of the flat-iron steak out there is not butchered that way. So, I guess not all flat-iron steak is tough.

Posted

OK, I am back home, so please find the reference:

Sous-Vide: Garen Im Vakuum

Viktor Stampfer

2009 Matthaes Verlag GmbH, Stuttgart

ISBN-10: 3875150279

ISBN-13: 978-3875150278

"The correct temperature for cooking sous-vide"

Chapter by Bruno Goussault pp.14-15

Noteworthy, the author cites microbiological studies performed at CREA.

Hi Mike - I have the Stampfer book and have just read the pages you cite. If one keeps reading to page 17 the following information is recorded:

"Conclusion

...............all vegetative forms of pathogenic bacteria are destroyed by thermal treatment, when the last phase of heat application is at around 56C and a core temperature of 54C has been achieved. After cooking at these temperatures, only the spores in products that have to be cooled rapidly after cooking and then stored at between 0C and 4C in order to avoid germination and further development........"

The author concludes by stating:

"There is a good deal of research to be done in order to progress beyond our present position of merely acknowledging and measuring the phenomena to the point where we will fully understand both the technical and scientific details. We will continue to study the subject."

This sounds far from conclusive, and is consistent with the advice from Douglas Baldwin and Nathan Myhrvold. Mr Goussault also discussed the lack of knowledge about the bacteriostatic and bactericidal properties of many flavour and aroma enhancers. This subject hasn't even been discussed here as far as I can see.

About the only thing I'm sure of is that there is more work to be done before we fully understand this interesting cooking technique.

Regards,

Peter.

Posted
Mike,

So, I guess not all flat-iron steak is tough.

Thanks, e_monster,

That is the point that I am trying to make. We have people form different countries (and different kitchens), so sometimes definitions get blurred.

I like this source:

Meat Buyers Guide

It's an expensive book, but one can "Look Inside!" on amazon.com.

Just for reference: Flat Iron is described on p. 18, cut number 114D.

"It's not from my kitchen, it's from my heart"

Michael T.

***************************************

My flickr collection

Posted

About the only thing I'm sure of is that there is more work to be done before we fully understand this interesting cooking technique.

Peter,

More in agreement with you I can not be - there is a lot work/research to be done.

Personally, I rely on empiric evidence ( and trial and error, as its integral part) rather than theoretical projections by even the greatest minds out there.

In conclusion, I would like to show you a picture of short ribs cooked SV:

gallery_57905_5970_30736.jpg

Short Ribs were cooked at 88C for 6 hours - wonderful texture. ( this plate was inspired by Alinea recipe)

"It's not from my kitchen, it's from my heart"

Michael T.

***************************************

My flickr collection

Posted

For what it's worth, I cut the large flat-iron muscle across the grain, and did not worry about the connective tissue that runs down the middle of the steak. I could have cut that out, but the steaks were already relatively small, and cutting them in half would have made them worse.

Had I realized that the Jaccard was going to flatten them so much, I would have cut them much thicker -- perhaps 2" or so. Next time.

The first attempt at 12 hours was definitely "blah" in both taste and texture.

Tonight, I served another batch cooked for 24 hours. These were better, but still not a home run. They were still a little dry, and any fat on the edges was relatively tough -- almost surprisingly so. Maybe I need to use the blow torch, rather than the hot skillet to sear the meat.

Another package is in the rice cooker tonight, still at 131F/55C, in order to try 48 hours -- the way I have done brisket very successfully. Since the brisket is from a close neighbor of the flat-iron, I hope it will work as well.

One question that I have concerns the au jus that is poured off of the steak. It is rather red, presumably indicating some blood. I've tried adding a little wine, with or without some flour, to make a quick gravy, but the results are an unappetizing gray, and not particularly flavorful.

Any suggestions from anyone?

MikeTMD, I will put the Stampfer book on my list, after the Joan Roca book arrives, and after I order the Fat Duck cookbook. How good is the translation? Although I can read and perhaps speak German from 50 years ago, I'm certainly not fluent.

Posted

To the best of my knowledge, botulism and other anaerobic bacteria multiply DESPITE the absence of air, and not BECAUSE of it, and it takes weeks for the spores or toxins to become dangerous, unless you do something really stupid.  Someone please correct me if I am wrong.

Bob

I am pretty sure that you are incorrect -- at least as far as clostridium botulinum which only grows in the absence of oxygen (or very low oxygen environments). The presence of oxygen kills the bacteria.

Some anaerobic micro-organisms can survive in oxygen-rich environments but many require low oxygen environments to survive.

Posted
The steaks were freshly cut from a larger piece of meat, and it was the fresh-cut sides that were Jaccarded, so those sides were presumably sterile until 30 seconds ago.  (And it wasn't the blades that compressed the meat, but the bottom of the Jaccard -- I think the spring mechanism used for safety is too strong.)

The knife came out of my knife block, so it was clean but not sterile.  The Jaccard had come out of the dishwasher with a sanitize cycle, but it had been exposed to the air, and the plastic cutting board had also gone though the dishwasher but been exposed to the air.

.....

To put all this in perspective, the number of automobile related deaths in 2008 was 37,313, so you are about 20 times more likely to be killed driving to or from the grocery store than from eating any of the products purchased there!

Robert,

I think you misunderstand the issues of sterility. Even if you use a sterile knife, if there is contamination on the outside, the knife can spread the contaminants. Once the knife cuts, those previously interior surfaces may now be contaminated. Also, if the meat gets wrapped up, the moisture will help carry contamination from one part of the outside to another.

For food safety reasons, it is generally considered an assumption that any uncooked exterior surface is contaminated and that any cut is carrying contamination to the newly exposed surface.

The primary issue is spreading the contaminants already on the meat NOT picking up additional contaminants from the air. Of course, you want to be using clean utensils, too. But even if all the utensils are sterile, you will run into trouble if the meat is contaminated. And contamination does not only happen to low-quality meats in cheap supermarkets.

Fyi, this is why any time you get a shot at the doctor's office or any time that you are going to be cut open with a scalpel. the area where the puncture or incision will be made is sterilized with alcohol. True that most of the time one will be lucky -- but why take the risk since it is very easy to reduce the risk with simple precautions without giving up great food.

If you are only worried about dying from the food, the risk is probably pretty small -- however, a HUGE number of people get pretty sick every year from food-borne contamination.

Many people don't even realize that the 'stomach flu' that they got was likely due to eating contaminated food (in the U.S. the estimate is that about 50% of 'stomach flu' is food borne illness such as salmonella or e. coli or listeria).

If you have ever had a bad 'stomach flu', consider whether or not it would be worth taking simple pre-cautions to avoid getting it.

Posted

e_monster, we are close to beating this subject to death, but I agree that food safety is important, and so the issue needed to be aired.

I'll grant that even if I cut into a previously-sterile muscle with a clean or even sterile knife, there is the possibility that some surface contaminant was carried to the new surface, and that by Jaccarding that surface, there is a further risk that the contamination would be carried into the inside of the meat, where it would not be killed by post-SV searing. The real question, for which we do not have sufficient data, is the probability of each occurrence.

Let's say that the probability of a "significant" (whatever that means) level of contamination on the surface of the Cryovaced primal cut was 10%. Let's also assume that the probability that each successive cut into previously sterile meat carried some contamination with it is also 10%. Finally, we might assume the chance of some resulting contamination actually causing an adverse reaction is also 10%. Then we have 10% (primal) * 10% (butcher) * 10% (my slice) * 10% (Jaccard) *10% (reaction), or 10^-5. If I were to cook and eat a flat-iron steak in this fashion TEN times a day for the next 30 years, that suggests that I might get sick ONCE!

One could certainly quibble with each of these probabilities. I tend to think that 10% is probably way too high, just thinking about the ratio of the surface area, but you might be more pessimistic. If any microbiologist would like to actually measure these probabilities, I'd certainly be curious as to the results.

So what is the bottom line here?

Is the answer to always pre-sear the meat, and/or never Jaccard it?

Personally, I've decided I'm not going to worry about it. Likewise, I'm not going to sear or boil my scrap or stew meat before grinding it for hamburger or chili. Your mileage may vary.

I do stand corrected on clostridium botulinum, however. The presence of oxygen kills these cells. And although it is unlikely that home-type vacuum devices such as a FoodSaver completely eliminates all the air in a bag, it is not impossible that a small pocket might exist that is relatively oxygen-free. Refrigeration below 38F appears adequate to prevent the growth of the organism, as do temperatures above 122F. See http://www.ext.colostate.edu/pubs/foodnut/09305.html.

Bob

Posted

Is the answer to always pre-sear the meat, and/or never Jaccard it?

That is not an accurate characterization of the options.

It is safe to jaccard without pre-searing if you are going to cook with a temp/time combination that pasteurizes the food (24 hours at 131F for instance would be totally safe to jaccard but 131F for 30 minutes would not).

The safe thing to do depends and the time/temperature that you will be using to cook. If you are cooking at a temp/time that does not pasteurize meat, you should sear (or parboil for two minutes) before jaccarding. If you are cooking at a time/temp that pasteurizes the food then jaccard to your heart's desire.

(Cooking stew pasteurizes the meat so there is no danger if you jaccard).

You can, of course, take whatever risks you would like, but I believe in people making informed decision and the previous discussion may have given someone the impression that if you cut a piece of raw muscle meat with a sterile knife on a clean surface that you can consider the newly exposed surface uncontaminated. If they made a decision thinking that is true then the decision would not be informed.

Keep in mind that the likelihood of a bad outcome is multiplied by the number of times that the event is repeated. Let's say the odds were 1 in 100 hundred that

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