Sous Vide Techniques & Equipment

[Anonymous Modernist 18404]

I am new to sous vide and am interested in using it to cook steak. I have a 2" thick, 10-12 oz filet that I would like to cook for a week night dinner. I am afraid that if I wait until I get off work at 5:30pm to set it up and get it in the water bath that it would push dinner too late. (We prefer to eat at 6:30). Is it possible to put the steak in at lunch and have it go 5-6 hours in the bath or would that be too long? I am not sure how long beef can stay in the bath after it has reached the target temperature without changing the texture of the meat. I'm also open to hear about any ways that you are using your sous vide to minimize the stress of busy weeknight dinner.

Thanks!

[Anonymous Modernist 18404]

As a follow up question/comment. We normally buy steaks in bulk so many of our steaks are frozen. I know that you can cook them sous vide from a frozen, would that be a way to cook them for a week night dinner that I'm starting at lunch? Are there any food quality or safety concerns that I should take into consideration?

[Anonymous Modernist 310]

It depend on the temperature where you cook your steak. With 2" steaks you don't have time to cook it at night. It should take about 3 hours from the fridge or 5.5 if you start frozen. There should be no problem starting it at lunch. If you cook at 54C or more there should be no concerns about safety as long as you don't overcrowd your bath.

Good luck

Louis-Frederic

[Anonymous Modernist 18404]

Thank you so much!!

[Karlos1968]

Hi, I have just bought a chamber vacuum sealer for my kitchen.

The thing is very programmable with vacuum adjustable to 99 seconds.

My question is; often on recipes it says something like 'seal to 95% vacuum' etc. does this refer to 95% of the 99 seconds? As it seems to reach max vacuum by about 60 seconds in any case.

Thanks

Karl

[dcarch]

If your are using the machine for sous vide cooking, the purpose is to have most of the air out for better heat conduction.

Therefore a good vacuum is not that important. Many people, including me, don't even use a vacuum.

For food storage, that's another story.

dcarch

[Steve Irby]

I think the standard being referred is one atmosphere or 29.92 inches of mercury. As you get more familiar with the machine you will see that the time it takes to reach the target vacuum is primarily a function of how much space is taken up by the object being vacuumed.

[Karlos1968]

Thanks that makes sense, so it would be 95% of the max vacuum (or should it be least vacuum) achieved?

I mainly got the chamber sealer because I want to experiment with it, already used it on a purée which made it very smooth. Also want to get away from the embossed bags which leave marks on the food!

Karl

[pbear]

Thanks that makes sense, so it would be 95% of the max vacuum (or should it be least vacuum) achieved?

Correct. That's plenty for sous vide, which as dcarch mentions, is mainly about good contact with the water bath. Stronger vacuums are mainly for compression, e.g., of fruits like watermelon. BTW, which machine are you using?

[Karlos1968]

It's a DZ-260 / PD not sure what brand it is though

Karl

[pbear]

Interesting. A little googling turns up two different Chinese companies claiming the product: Hualian (here, here and here) and Dajiang (here and here). Of the two, the first seems more credible to me, though it's also possible the two companies are related. Meanwhile, it seems to be distiributed in the U.S. under the tradename DMC. In Oz, it's credited by one dealer to 3Monkeez. In Indonesia, it's claimed by PowerPack. And so on. Where are you located, by the way? And, if you don't mind explaining, how did you come by the machine?

[Karlos1968]

I am UK, was bought from China as a sample machine by a local company who make packing machines. It never got out of the box there. I got from them.

[johnder]

That sure looks a lot like the Ary 215 model. (versus the 210, since there is a bottle of oil in the photo, which is also the exact bottle that came with my 215)

[rotuts]

I love studying C.V.S.ers

if you go the **** excellent **** ref above and click on the blue 'DMC' ref, then scroll down to almost the bottom of that page you

will see the differences between machine

I am very surprised there are so many varieties of these things.

[sculptor]

It's a DZ-260 / PD not sure what brand it is though

Karl

Looks close to what I've got. If you use the pressure gauge you should be able to determine 95% pressure (0.05 bars of pressure) and hit the stop vacuum button then it gets there. If you jot down the number of seconds it took to get there you can program your machine to do that. Note, too much vcacum is only bad for delicate ingredients so a little extra time at maximum vacuum won't hurt other things...

Edited January 3, 2014 by sculptor (log)

[pbear]

Agreed. As discussed upthread, Karlos, it's the pressure reading which counts, not the timer. From the picture, it appears you have the manual. (Which, indeed, was the main thing I was searching for and couldn't find online.) From there, it should be fairly straight forward to make the adjustment sculptor suggests.

[Adam George]

Did you get a good price? I'm in the UK, too.

[mgwalter]

I agree with the previous posters that for sous vide in a water bath, your goal is just to remove enough air so that when you are immersing your food it rests in the water and doesn't float to the top. The danger of going too far and too long in the vacuum sealer is that when you've lowered the pressure too much liquids will boil at room temperature. If you are sealing a nice cut of meat and hold it in the vacuum too long, the liquid in the beef will boil and change the texture, generally not in a desirable way. For fruits and vegetables, you may be wishing to get that texture change, so knowing the boiling point is key.

You mentioned you got the sealer for experimentation, so why not spend some time experimenting with how it works before you try experimenting with recipes? Try sealing bags of water at different temperatures to see what you can get away with before they begin to boil. Use this as your guide. Learn how long you can go before the pressure results in refrigerated liquid boiling. Buy some cheap cuts of meet, say chicken legs, and see how long you can go before you've "cooked" them in the chamber (and throw them away; please don't taste them even if the boiling juices made them less pink). You can even use dried beans or uncooked rice (or things which aren't edible, like spoons and forks) to get a feel for how long you need to seal to remove enough air for full immersion in water.

I regularly use my vacuum to package food that I've cooked for freezing, and this experimentation has been very helpful in my understanding how long I need to wait for things to cool down before I can seal the food after it's been prepared - do I need to put it in the fridge overnight, or will a few ten minute rests surrounded with cold water in the sink be enough? Can I go for 20 seconds before boiling a bag of 80F degree chili, or is it better to wait until the next morning when it's at 38F? Do I need to go longer for food which might trap air, and how long can I go when sealing dry ingredients where the risk of boiling is far less? Where should I place food in the bag to allow for air to easily escape? I find myself disappointed if I'm not minimizing the freezer burn as much as I thought I could when taking things out of the freezer. Spending thirty minutes with the vaccum sealer, thirty bags to potentially waste, and lots of objects has resulted in my learning the sealer like I would a new pot or pan.

As you are spending time learning your vaccuum, be sure to vaccuum seal ice cubes. They'll go from solid to liquid, and then when the pressure rushes back in it'll return to a solid state immediately. Very cool.

I've had a blast with my chamber. No regrets whatsoever in buying it. My wife thought I was crazy to purchase it due to the high price and size, but she's more than willing to assist now that she understands the options it gives us.

My gut tells me you can ignore the explicit directions to "seal to 95%" and instead, just get enough air out so you aren't left with a bag floating in water or the texture you want when you are simply playing with pressure. Learn the timing if your machine through experience and you'll be in great shape to consistently get the pressure you need without wasting bags or destroying the texture of the food you are sealing.

[pbear]

Welcome, sir, to the forum. I will respectfully disagree with you on one point. Boiling during vacuum packing bears no resemblance to boiling in the ordinary sense. The latter implicates protein contraction, where the former does not.

[Docrjm]

Matt, the boiling observed in a vacuum is not due to heat, so the meat is not cooked and the proteins are not denatured to the point of being "cooked". Meat thus packaged can be safely frozen and or cooked conventionally, or indeed sous vide. It certainly does not need to be thrown out.

[mgwalter]

Pbear & Docjrm - this is good to know. By no means did I intend to indicate anything was cooked by the presence of liquid turning to gas, rather I'd always assumed (based on nothing but my own mind or something I read in the past), that the boiling of the liquid would change the texture of the object being sealed. Is that not the case? If so, I'm probably being over cautious when I'm sealing packages of meat for a water bath.

[rotuts]

well, study study study:

try one meat item ' at the boil ' a similar cut just under the 'boil'

mark carefully and SV identically.

have someone else plate so you don't know what you are testing

I dont have a chamber vac, so I cant do this study myself.

very little to loose here.

[Karlos1968]

sorry for my tardy replies, I have not had access recently.

Thanks for all the advice above, I have decided to do a course with Sous Vide Tools next week, so hopefully will get some hands on tips from it.

I have started to tone down the vac timing as some things (scallops) were getting squished!

I will definitely try the ice trick.

A question over cost was asked, I bought it from a company is Essex through eBay, they brought it over from China but never used it.

Thanks again,

Karl

[Samo154]

Wondering what temperature most kitchens cook there food at sous vide? Most places I've worked cook at 62c and hold at 50c wondering what everyone else does? And why?

Also is there a difference if u cook at 60c or 70c apart from speed. We probe all the food so would it make a difference?

[nickrey]

May I suggest that you look at the sous vide topic index. It has many suggestions for cooking temperatures.

 

The bottom line is that cooking sous vide is a function of temperature and time and both need to be adjusted to achieve your desired outcomes.

 

For proteins, the only thing I'd cook at 62C is dark chicken meat.

 

Even if you use probes, the temperature is important as it affects the uniformity of the product. Using a higher temperature gives you a gradient on the product (more cooked on the outside layer, less in the middle). This means for a steak that you might wind up with medium well on the outside and medium rare in the middle. Good for conventional cooking, perhaps less so for sous vide.

 

If you want a good, practical, way of looking at cooking temperatures and time, check out the sous vide dash iphone app.