1176 replies to this topic

[dougal]

How to Steal a Four-Star Chef's Secret Cooking Technology—By Building It Yourself

This was on Gizmodo today.

Slow cookers ("crockpots") are available fairly cheaply. But they are far from ideal.
Generally a bit small and shallow. A deeper bath, allowing the bags to sit vertically, is a better choice.

One advantage that crockpots do have is that their heaters are quite weak. The low wattage means that it is possible to switch them with the relay built into some 'temperature controllers' without frying the relay.
However, relay control via a 'dumb' controller isn't going to give great control.

Better to get a PID controller with autotune and SSR-controlling output, an SSR (Solid State Relay) to do the switching safely and without any fuss (and as frequently as you care to dial in - mine is 'on' for a variable proportion of a 2 second cycle), and ideally your PID will have the option of using a more accurate "PT100" probe, so that's the type you'd choose (do make sure its "fully immersible" - works under water!)
For example, if you went to Auber, you'd likely end up with less cost* than the $90/95, dumber, less accurate, less stable (but simpler) controller suggested by the Gizmodo author. And you'd be able to switch more powerful heaters ... Or to avoid the assembly, go up from Gizmodo's $90/95 to $139 and get the $139 ready-built sous vide controller
* $45 for the PID, $26 for the SSR & heat sink, $16 for the PT100 probe, making $87 total


While the Gizmodo rig could work, you could do much better, either with better components for the same sort of price, or for the DIY-averse, even ready-made and in a nice case for not much more money.

Edited by dougal, 05 November 2010 - 04:09 AM.

[Montreal]

Some more results from the lab.

Veal cheek again at 135F for 24 hours. Good texture but still a fair amount of Callogen.
Next test at 135 F for 36 hours and 48 hours.

Just got the book Sous Vide from Joan Roca and Salvador Brugués.

Cannot wait to explore the book over the weekend.


I will keep you posted on the next results

[nickrey]

Thanks for doing the tests, looking forward to the results. I take it the meat is all from the same source?

[Montreal]

Yes all the Veal Cheek are all from the same farm.

Now that I start looking at the book they suggest that( Veal Cheek) should be done at 68 Celcius for 18 hours... There we go, another test in the pipeline.


Stay tune.

[PedroG]

Dan,
thanks for doing all the tests!
Trying 68°C will be a valuable service to the community to verify the theoretical expectation that above 60°C there should be no collagenase activity and below 70°C there should be poor/slow collagen melting. I never did something of which I expected a poor outcome. Thanks again!

[nathanm]

Dan,
thanks for doing all the tests!
Trying 68°C will be a valuable service to the community to verify the theoretical expectation that above 60°C there should be no collagenase activity and below 70°C there should be poor/slow collagen melting. I never did something of which I expected a poor outcome. Thanks again!

The situation is nowhere near that clear.

First, there are many enzymes that affect tenderness. Some of those enzymes denature (and thus stop working) at various temperatures between 40C/104F and 70C/158F. However there do not seem to be any sharp cut offs.

Degrading collagen by enzymes is one of things that occurs, but the primary collagen effect is due to heat and water alone. Collagen does not "melt" in the usual meaning of the term. Instead it undergoes a process which has many names (hydrolysis, denaturation, gelatinization...) when heated with water, which converts it into gelatin.

This process starts at very low temperatures. Exactly how low is a subject of a lot of debate in the scientific literature. It likely starts just above normal animal body temperature, but the rate is very low. Most chemical reaction rates vary exponentially with temperature, so as the temperature gets low the rate becomes so slow that you must be very patient.

Many food science books make ridiculously wrong statements, saying that collagen does not undergo hydrolysis below 60C/140F. That can trivially be shown to be false by sous vide cooking at 55C/130F. You need to do it for a long time (24 to 72 hours), but it surely works, as people on this threat all know.

The 60C/140F number comes from a 1971 scientific paper, which just wasn't patient enough at the low end of the temperature scale. More recent work on collagen has shown that the effect starts at 50C/122F but likely goes even below that (but at a very slow rate).

[Montreal]

I agree with Nathanm.The statement that the calogen is not reacting or very little over 70 C is a myth as I did several experiment on Beef and Pork on temperature ranging from 74 c to 82 C and their was tons of Collagen reaction.

The best meat texture that I had so far are actually on Pork cheek for 12 Hours at 74 Celcius. This is why I might actually like the 68 C for 18 hours on Veal. We shall see

Ultimately converting all the calongen into gelatin might NOT be the Ideal meat texture and taste that someone is looking for. Personal preferences are hard to judge and consequently I think that part of the difficulty with sous vide is that their is so many variable to play with and everyone has it s own opinion on how they like their meat not only from a doness perspective but taste, texture etc...

I so far find that if I convert the most possible Calogen into gelatin in Cheek, the meat is very tender but also stringy and loose. Braising in a pressure cooker would actually give me the same results in a much faster time with similar meat texture. This is why experimenting is so much fun, as I am looking for the same tenderness of braising with a completely different texture and Doneness

As I am using sous vide: I am in constant search of a texture and taste that I could not duplicate any other way.



Thanks for sharing.

[nathanm]

I agree that the key to sous vide is achieving things not possible other ways. Pressure cooking is indeed faster if you don't mind what it does to the meat (grayness etc). Once you go to 70C or above that is pretty much a moot point so pressure cooking is a viable alternative.

Also, there is no one right answer. Short ribs can be good over a wide range of temps and times - you get VERY different results, but depending on what you are looking for it, any of them could be "ideal".

[andrewk512]

Treated the same as most tough cuts I do 73c for 48 hours produced a tender awesome boned beef shank. Picture was from my first attempt, I've since adjusted for just a more of a medium rare.

So my Sous vide magic is off by a crazy 15c. I am not the most tech savvy guy, any of you SVM guys know how to fix?

I'd love to try this soon. I'm just wondering if there are any botulism concerns with cooking meat this long at a low temp? And would this 53c/48hr work for 1.5" pieces of beef shank?
Thanks =)

[PedroG]

1. I guess the "53°C" was a typo as 73°C minus the 15°C error yields 58°C.
2. 53°C/127.5°F is the growth limit of Clostridium perfringens, see FOOD PATHOGEN CONTROL DATA SUMMARY . 54.4°C/130°F is the limit for safe long-time cooking. See also FOOD SAFETY HAZARDS AND CONTROLS FOR THE HOME FOOD PREPARER .
3. Cooking at the minimal safe temperature requires reliable thermometer accuracy, see Thermometer calibration.

Treated the same as most tough cuts I do 73c for 48 hours produced a tender awesome boned beef shank. Picture was from my first attempt, I've since adjusted for just a more of a medium rare.

So my Sous vide magic is off by a crazy 15c. I am not the most tech savvy guy, any of you SVM guys know how to fix?

I'd love to try this soon. I'm just wondering if there are any botulism concerns with cooking meat this long at a low temp? And would this 53c/48hr work for 1.5" pieces of beef shank?
Thanks =)

[Chris Amirault]

Speaking of shanks, just put up four lamb shanks at 70C for 48h. Used a rub with ras al hanout and Aleppo pepper, and added a mixture of chicken fat and butter that we had used for dipping artichokes earlier in the evening. Will report back.

[Chris Amirault]

Very happy with the shanks, though I think I'll try 68C next time: the meat was just starting toward a drier texture, making me wonder what a tick or two lower would do. It was tender as the dickens, though...

[nickrey]

Very happy with the shanks, though I think I'll try 68C next time: the meat was just starting toward a drier texture, making me wonder what a tick or two lower would do. It was tender as the dickens, though...

I take it from your description that the collagen softened. Seems this temperature/time and collagen conversion thing gets me more and more confused the more I read and experiment. Roll on Nathan's book I say.

[Chris Amirault]

The collagen definitely softened: the only remaining sinews were at the very base of the shank where the muscles become slender and the tendon connects.

[ojisan]

What does one do with the accumulated juices from, say, a steak? Are they usable as a sauce, au jus etc.?

[PedroG]

What does one do with the accumulated juices from, say, a steak? Are they usable as a sauce, au jus etc.?

See some earlier posts:
nickrey post 2419 (extracting osmazome)
and posts 3198 to 3204 (usage of the gravy from LTLT cooking)
and one of my favorite recipes (Brisket Stroganoff).

[ScottyBoy]

Would you say moisture retention is enhanced buy cooking SV then shocking just like cooling braised meats in their cooking liquid is key?

[ojisan]

Thanks Pete - I was wondering about all the coagulated meat proteins. Confirms my thoughts.

[nickrey]

Addendum to what Pedro posted:

I used to boil the juices to coagulate the proteins and then used the strained liquid (osmazome) for sauce making.

Looking more carefully at the proteins that were coagulated, they seemed to be the residue that the meat would put out whilst frying that then cooked onto the bottom of the pan and would later be deglazed to make a sauce.

Using this reasoning, I now heat the liquid and strain off the osmazome, which I add later in the sauce making process.

I then cook the remaining residue at a sufficient temperature for it to be undergo a Maillard reaction and give the approximation of the bits that stick to the bottom of the pan when you fry meat. I then deglaze with an appropriate liquid (typically red wine, which I then reduce) and proceed to make the sauce, adding an amount of the osmazome as one of the components (as well as chicken stock, veal demi glace and an acid just before serving).

Once the sauce is cooked down to a suitable thickness or thickened with a starch such a potato starch (this call depends on the flavour of the sauce and the degree to which it will cope with being further concentrated), I strain it and serve it over the meat.

The flavour of this sauce more closely represents a traditional sauce due to incorporation of the meaty, maillardized flavours.

Edited by nickrey, 12 November 2010 - 08:25 PM.

[Montreal]

Another puzzle.

So far all my test were on red meat. I tried some scallops at 49 Celcius... They were awfull.

Any recommendation


Tks

[nickrey]

Scallops cook so quickly and the searing gives such a nice caramelization I don't think I'd even want to sous vide them.

[e_monster]

Scallops cook so quickly and the searing gives such a nice caramelization I don't think I'd even want to sous vide them.

Agreed.

[Montreal]

Yup... Actually I think so too. I also did some Red Deer 1 cm thick loin and they were so awsome seared that I dont think that it was worth it to sous vide.

Thaks for the reply

[MartinH]

I've been experimenting with SV custards of various kinds, that is egg-thickened creams such as crème brûlée, crème anglaise, cheesecake, pumpkin pie, and even eggnog.

A few things I've learned:

SV is an excellent method for cooking custards. While custards thicken when the egg proteins in the mix are heated, they curdle when the egg protein is overheated. Traditional methods to prevent curdling include preheating the milk, stirring, adding flour, or placing ramekins in a waterbath in the oven. But SV is much more accurate, more dependable, and far easier.

Preparing the mix couldn't be simpler. Its just a matter of combining the basic ingredients: egg, liquid, sugar, salt, and flavoring. The liquid can be milk, cream, coconut milk, cream cheese (for a chesecake) or variations and combinations thereof.

Ratios vary. An eggnog would be about 1 egg to 1 pint of liquid. A soft custard (English-style custard or crème anglaise) would have about 1 egg to 1 cup of liquid. Firmer custards would have a greater proportion of eggs. Either whole eggs or yolks can be used. Yolks add a little more color and richness, but do not have greater thickening capacity.

Some flavorings appear to work better than others in SV conditions. Vanilla is superb. But strong flavors such as citrus zest (often used in cheesecake recipes) or pungent spices (as in pumpkin pie filling) can be too harsh. Strong flavorings can be toned down by precooking, then cooling and adding to the custard mix.

A temp of ~83C/181F does the trick. Interestingly, this is higher than the ~64C/147F at which egg yolks set; diluted eggs in need a higher temp for their proteins to coagulate.

SV cheesecake or pumpkin pie clearly depart most from the traditional method, since the crust and the filling must be cooked separately. But the traditional method often produces a dry, cracked, hard product. SV cheesecake or pumpkin pie is much more creamy, soft, and delicate. A modernistic cheesecake sprinkled with cookie crumbs, or a new pumpkin pie garnished with a wedge of pastry can be fun.

Since vacuum sealers do not work well with liquids, custards can be cooked in ziploc bags or in small mason jars.

I'd be interested in hearing what anyone else has discovered in this area.

[ermintrude]

Doing them Sous Vide will work but seems over kill when tey can be done just as well on a hob, with good control and stirring. Or use a thermomix or the new kenwood if you want to do custards etc, with no attention they are perfect for that.

[Chris Birkett]

I'm planning to order one of the SousVide Supreme units in the next couple days. They have a special right now where you get their vacuum sealer with the SVS for only $20 extra. I'm kind of concerned about how basic this model is, missing features like pulsed vacuuming or multiple speeds. I recall reading earlier in the thread that you really want a fully-featured sealer for sous vide.

Should I even be considering the vac sealer they carry, cheap or not? The alternative would probably be something like the Foodsaver V2490, which is also fairly cheap but more fully-featured.

[Chris Amirault]

Hi Chris! I have to say that I've been happy with my FoodSaver (click here for information) and think that there's no need for a home user to upgrade to anything much more than that.

MartinH, thanks for that write-up. It's extremely useful.

What Nick wrote above is my procedure for those juices when I'm feeling virtuous. More often than not, however, my "sauce" isn't classical French but is a quick rustic one with sautéed onions or tomato sauce. So I just fine strain the contents of the bag, push the stuff in the strainer through the mesh, and add the stuff all at once into whatever sauce base I'm making. I'll also add that LTLT-cooked proteins with a lot of collagen in them -- skin, bones, tendons -- have thickening properties that mean that you can skip the cornstarch etc.

[gfweb]

I'm planning to order one of the SousVide Supreme units in the next couple days. They have a special right now where you get their vacuum sealer with the SVS for only $20 extra. I'm kind of concerned about how basic this model is, missing features like pulsed vacuuming or multiple speeds. I recall reading earlier in the thread that you really want a fully-featured sealer for sous vide.

Should I even be considering the vac sealer they carry, cheap or not? The alternative would probably be something like the Foodsaver V2490, which is also fairly cheap but more fully-featured.

I have a SVS and have quit on using a vacuum sealer for routine stuff. Careful expulsion of air from a normal zip lock bag (either by rolling or immersing in water and sealing the zip lock) has worked fine.

[Chris Amirault]

Dave Arnold over at CookingIssues.com likes the ziploks too.

[MartinH]

Doing them Sous Vide will work but seems over kill when tey can be done just as well on a hob, with good control and stirring. Or use a thermomix or the new kenwood if you want to do custards etc, with no attention they are perfect for that.

Far from being overkill, I find it easier to do a custard (defined broadly) by the SV method rather than in the traditional ways on the stove top or in the oven. Wouldn't it be overkill to purchase a thermomix or a new kenwood for this when a SV set up does the job just fine?

May I add that SV more generally is not unnecessary, not overkill, not more than is needed to do the job for the simple reason that it is often the best way to do the job.