• Welcome to the eG Forums, a service of the eGullet Society for Culinary Arts & Letters. The Society is a 501(c)3 not-for-profit organization dedicated to the advancement of the culinary arts. These advertising-free forums are provided free of charge through donations from Society members. Anyone may read the forums, but to post you must create an account.

  • product-image-quickten.png.a40203b506711f7664fc62024e54a584.pngDid you know that these all-volunteer forums are operated by the 501(c)3 not-for-profit Society for Culinary Arts & Letters? This holiday season, consider a tax-deductible Quick Ten Bucks to support the eG Forums and help us remain completely advertising-free. Thanks to all those who have donated so far!

paulraphael

ziplocks for cook-chill sous vide

25 posts in this topic

Dave Arnold and co. say yes, Nathan Myrhvold and co. say no.

 

Dave makes a good case for it and says that 90% of sous-vide cooking can be done without a vacuum, and that his food saver has been relegated to re-sealing potato chips. Nathan doesn't give a reason.

 

I don't understand why ziplocks couldn't be used for cook-chill applications. Don't we use them to store conventionally cooked food in the fridge?

 

Thoughts? 

Share this post


Link to post
Share on other sites

I agree with you and Arnold.

 

Only argument I can think of is that the zip loc might open in the fridge.

Share this post


Link to post
Share on other sites

Where does Myhrvold say no? From what I remember, he says you eliminate oxidation using vacuum bags which can increase keeping quality of cook chill foods. When you have a bajillion chamber vacuums like him, this is a no-brainer and he does stuff like chamber vac beans and water to hydrate them instead of just putting them in a bowl like a normal person.

 

For everyone else, just use ziplocks and don't think about it.


PS: I am a guy.

Share this post


Link to post
Share on other sites

I cook with sous vide bags, un-sealed.

 

It is very nice that I can taste test while the food is being cooked and adjust seasoning if required. For large piece of meat I can even probe temperature once in a while.

 

After cooking, I rinse the bags, turn them inside out and store them. After I have lots of them, I throw them in the clothes washer and they come out totally clean and good for the next round of cooking.

 

Bags are not cheap, and it take time to seal/unseal.

 

dcarch.

Share this post


Link to post
Share on other sites

Have a picture of the way you do it, Dcarch?

 

I'm trying to visualize an unsealed vacuum bag that isn't filled with air.

Share this post


Link to post
Share on other sites

I've been using zip locks for years with no problems - even with cook chill.  That being said, here and there I've had a problem once in a while with doing high temp stuff in a ziplock - like a confit at 176 for several hours - here and there one bag would leak.  But for most things, especially below say 150degF I've had no problems, and it's much more convenient.

Share this post


Link to post
Share on other sites

Where does Myhrvold say no? From what I remember, he says you eliminate oxidation using vacuum bags which can increase keeping quality of cook chill foods. When you have a bajillion chamber vacuums like him, this is a no-brainer and he does stuff like chamber vac beans and water to hydrate them instead of just putting them in a bowl like a normal person.

 

For everyone else, just use ziplocks and don't think about it.

 

I agree with you based on what I know. But Myhrvold does say otherwise.

 

 

“Strictly speaking, vacuum packing is only required (as a safety measure and to prevent oxidation) for cook-chill sous vide, in which the food is stored after cooking.”
 
and
 
“Zip closure bags are inexpensive and available at any corner store. Althought not suitable for cook-chill sous-vide, they can work well in a pinch for improvising sous-vide packaging”
 
I'm curious if there's any substance behind this. Might be that as you suggest, life without a vacuum machine is hust not a life he's ever imagined.

Share this post


Link to post
Share on other sites

I'd suggest it hinges on how reliable the seal is.  With a chamber/FoodSaver, sealing involves essentially melting teh two sides of the bag into a single layer.  Ziplocs are good, but can potentially come unsealed under conditions where the temperature, and thus 'direction' of any pressure differential, are changing rapidly.  As when you put a hot bag in a bowl of ice and water.


Leslie Craven, aka "lesliec"
Host, eG Forumslcraven@egstaff.org

After a good dinner one can forgive anybody, even one's own relatives ~ Oscar Wilde

My eG Foodblog

eGullet Ethics Code signatory

Share this post


Link to post
Share on other sites

I cook with sous vide bags, un-sealed.

 

It is very nice that I can taste test while the food is being cooked and adjust seasoning if required. For large piece of meat I can even probe temperature once in a while.

 

After cooking, I rinse the bags, turn them inside out and store them. After I have lots of them, I throw them in the clothes washer and they come out totally clean and good for the next round of cooking.

 

Bags are not cheap, and it take time to seal/unseal.

 

dcarch.

 

I can't see doing this.  Bags seal in well less than a minute, and take seconds to cut open.  It costs $2.00, in quarters, for me to do a load of wash.  New bags are 20 cents a piece, and I don't have to go out in the snow.

 

If I had a washing machine in my kitchen rather than a chamber vacuum sealer I might feel differently.

Share this post


Link to post
Share on other sites

Notice that Dave Arnold says, towards the bottom of the linked article, that one of the disadvantages of ziplocs is that they don't permit the same extended storage as vacuum bags.  Frustratingly, he never says how long he thinks ziplocs are okay for cook-chill, so the advice isn't very useful.  Personally I'd hesitate to rely on ziplocs for holding any longer than open leftovers (three days to a week, depending on fridge temp).  My experience with ziplocs when used for general storage (don't do cook-chill) is that they allow in air rather easily over a period of days even without the seal failing.

Share this post


Link to post
Share on other sites

Notice that Dave Arnold says, towards the bottom of the linked article, that one of the disadvantages of ziplocs is that they don't permit the same extended storage as vacuum bags.  Frustratingly, he never says how long he thinks ziplocs are okay for cook-chill, so the advice isn't very useful.  Personally I'd hesitate to rely on ziplocs for holding any longer than open leftovers (three days to a week, depending on fridge temp).  My experience with ziplocs when used for general storage (don't do cook-chill) is that they allow in air rather easily over a period of days even without the seal failing.

 

Isn't a week as long as you'd ever do cook-chill?

Share this post


Link to post
Share on other sites

Am.Test Kitchen did a 'study' of plastic storage bags for the freezer.  zip-loc's, zip-loc's w the extraction hole if you will, regular plastic

 

Food saver and the Weston ( 400 $$ ) system.

 

they found that after  ( paraphrasing here ) 1 - 2 months in the freezer ice crystals in the bag penetrated the plastic and the contents were t

 

then subjected to 'freezer burn'

 

the Weston system w the thicker 3.5 MIL bags did not do this and lasted .....

 

I got the Weston system 3 years ago or so to begin my SV studies.  none of these bags have failed me after I understood how clean and 

 

dry  the bags needed to be at the seal.

 

Ive had stuff SV in my freezer thats over a year old:  seal good, tastes fine.

 

so   cooking and saving for a brief period of time is one thing, freezing for a long time is another.

 

i also store my green coffee beans this way, but not in the freezer:  just a very cold basement.

 

so the thickness of the bag will determine who long the contents might keep,   + / -

Share this post


Link to post
Share on other sites

I can't see doing this.  Bags seal in well less than a minute, and take seconds to cut open.  It costs $2.00, in quarters, for me to do a load of wash.  New bags are 20 cents a piece, and I don't have to go out in the snow.

 

If I had a washing machine in my kitchen rather than a chamber vacuum sealer I might feel differently.

 

As I said in the above post, there are more reason than just $. In any case, I use boil-able heavy duty bags which are $0.40 each. And recycling means a lot to me.

 

Shopping, buying takes time too.

 

dcarch

Share this post


Link to post
Share on other sites

Have a picture of the way you do it, Dcarch?

 

I'm trying to visualize an unsealed vacuum bag that isn't filled with air.

 

Sure. Also someone had asked about how I weigh my bags down.

 

dcarch

 

bagweight_zps24a71d54.jpg

 

bagweight2_zpsbe4f4fc9.jpg

 

bagweight3_zpsc9417034.jpg

Share this post


Link to post
Share on other sites

Looks like a lot of air in the bag.

 

How do you deal with that? Fill the bag with fluid?

Share this post


Link to post
Share on other sites

Looks like a lot of air in the bag.

 

How do you deal with that? Fill the bag with fluid?

 

There will be very little, if any, air inside.

 

The bag will have some marinade, seasoning, or sauce. The meat will give out some juice once heated. The hot water softens the plastic bag, and the heavy weigh holds down the bag to allow hydro-static pressure to squeeze out the air.

 

dcarch

1 person likes this

Share this post


Link to post
Share on other sites

Isn't a week as long as you'd ever do cook-chill?

Baldwin gives cook-chill times up to 90 days for very cold storage, presumably for vacuum bags though it's not expressly stated.  Indeed, in my understanding, this was one of the main advantages of sous vide when first developed as a commercial process.  Anyhoo, circling back to the OP, if you're only looking to hold for a week, I think even Nathan would agree ziplocs are okay.

 

And, gfweb, as for your question to dcarch, bear in mind that pressure from the water will evacuate the air, just as when loading ziplocs.  So long as the food stays below the water line, there's no way for the air above to get at it.

Share this post


Link to post
Share on other sites

As I said in the above post, there are more reason than just $. In any case, I use boil-able heavy duty bags which are $0.40 each. And recycling means a lot to me.

 

Shopping, buying takes time too.

 

dcarch

 

If you are going to wash the bags I don't see why you could not reseal and reuse the same bag several times.  The 20 cent bags are boilable.  If your bags are retort bags that could be used in a pressure cooker I would probably be interested to buy some.

Share this post


Link to post
Share on other sites

I've done a lot of experiments with sealing in Ziploc bags.....they're not dependable in terms of staying sealed and some folks consider them quite permeable.

If you want to cook-chill foods with confidence....use better bags.


~Martin

Unsupervised rebellious radical agrarian experimenter, minimalist penny-pincher, self-reliant homesteader and adventurous cook. Crotchety cantankerous terse curmudgeon, nonconformist, contrarian and natural born skeptic who questions everything!

The best thing about a vegetable garden is all the meat you can hunt and trap out of it! 

 

Share this post


Link to post
Share on other sites

Frustratingly, he never says how long he thinks ziplocs are okay for cook-chill, so the advice isn't very useful.  

 

Some Ziplocs stay sealed well for an extended period of time and some don't so it's impossible to honestly estimate how long they'll stay sealed.


~Martin

Unsupervised rebellious radical agrarian experimenter, minimalist penny-pincher, self-reliant homesteader and adventurous cook. Crotchety cantankerous terse curmudgeon, nonconformist, contrarian and natural born skeptic who questions everything!

The best thing about a vegetable garden is all the meat you can hunt and trap out of it! 

 

Share this post


Link to post
Share on other sites

If you are going to wash the bags I don't see why you could not reseal and reuse the same bag several times.  The 20 cent bags are boilable.  If your bags are retort bags that could be used in a pressure cooker I would probably be interested to buy some.

I guess you are still missing part of what I said above"----It is very nice that I can taste test while the food is being cooked and adjust seasoning if required. For large piece of meat I can even probe temperature once in a while.---"

 

Each time you cut and seal, the bags get smaller, soon I will have close to a hundred bags of various sizes to manage. I have found that the cheaper bags have the problem of the "quilted" layer delaminating after a few cooks.

 

darch

Share this post


Link to post
Share on other sites

Maybe I am missing something else, but if you are not using an edge sealer, why use quilted bags at all?

Share this post


Link to post
Share on other sites

I'd love to see some experimental evidence on foods cooked to pasteurization in ziplock freezer bags and stored at a range of standard fridge temperatures. 

Not really a home experiment. You'd want lots of samples, a few different types of food, and a range of fridge temperatures. Real life fridges add a lot of variables with their temperature swings.

And you'd need a biology lab, and some agreed-upon standards.

Share this post


Link to post
Share on other sites

Maybe I am missing something else, but if you are not using an edge sealer, why use quilted bags at all?

 

A very good question.

 

1. I do, very seldom, vacuum and seal. Although I don't remember when was the last time.

 

2. I trust more the plastic used for boil-able  bags specifically designed for high temperature sous vide water baths. I made clotted cream yeaterday, at 180F for 10 hours.

 

3. And this unique use I came up with. As I said, I am interested in recycling and re-purposing materials.

 

 

dcarch

Share this post


Link to post
Share on other sites

I'd love to see some experimental evidence on foods cooked to pasteurization in ziplock freezer bags and stored at a range of standard fridge temperatures. 

Not really a home experiment. You'd want lots of samples, a few different types of food, and a range of fridge temperatures. Real life fridges add a lot of variables with their temperature swings.

And you'd need a biology lab, and some agreed-upon standards.

 

To my knowledge, no such study has been done, which may expain why Dave Arnold was so vague.  But, again, if you're only looking to hold for a week, existing food handling protocols say that's okay, so long as the temp stays below 41F.  See FDA Food Code, § 3‑501.17(A)(1) (scroll down the page about two-thirds of the way).  Whether your fridge actually holds this temp is the bigger issue.  I monitor mine with a thermometer.

Share this post


Link to post
Share on other sites

  • Similar Content

    • By Franzisaurus_Rex
      FOOD BRETHREN!
      I need some advice. I have one last piece of pork belly confit in the fridge. I brined these bitches for about 5 days (brine included pink curing salt), vacuum sealed the squares of pork belly with lard and sous vide them at 158 F for 16 hours. I cooked this on 11/10/16 and its been in my refrigerator since. 
      Here is the general recipe I followed, with some modifications based on my taste: https://www.chefsteps.com/activities/...
      The last piece is still vacuum sealed and submerged (mostly) in lard. Any visible pork only has contact with the bag. 
      It's staring at me. And calling my name.
      I want to deep fry this sucker and have a little date night with the handsome devil I see in the mirror every morning, but the last thing I want is spoiled food. I can't find any conclusive information about how long pork confit lasts for. I've only seen references that duck confit or in general that the confit technique will last for months in the fridge. I have found no sources which directly addresses pork confit.
      Questions/Factors I'm Considering:
      - Does pork confit keep for as long as duck confit?
      - Does vacuum sealing have any effect on the length of preservation?
      - Does sous-vide cooking method affect the length of preservation?
      I know I am probably being a bit paranoid, but I thought I would do my due diligence before taking the plunge, so to speak. Any advice on these questions would be extremely helpful and appreciated!
      The Franzisaurus-Rex
      PS - you should totally make this if you are into sous vide, confit, food, or have any respect for the enjoyment of life. Flash-searing these things after cooking was OUT OF THIS WORLD.
    • By JoNorvelleWalker
      The NY Times has a current article in the science section "A Universe of Bubbles in Every Champagne Bottle".
       
      The article asserts that it is better to serve Champagne at warmer than refrigerator temperatures so that the bubbles are larger and convey more flavor.  Also to serve in a narrow glass.
       
      However Gerard Liger-Belair (who is referenced as an authority in the Times article) points out in his book Uncorked (forward by Herve This) that the colder the wine the more viscous and the more dissolved CO2.  Liger-Belair also prefers a goblet to a flute.  I bought Uncorked after reading about it in Liquid Intelligence from Dave Arnold.
       
      Discuss.
       
    • By weedy
      I made a Gellan based fluid gel that I think is 'too thick'.
      (One could say, I'd like more fluid and less gel!)
       
      Anyone know what the best way, if any?,there is to thin it so I can squeeze bottle it? at the moment it's spoonable but way thick.
       
      Could I add water and blender it again?
      or is there another idea?
       
      thanks in advance.
       
       
    • By Gary Burns
      Hello,
       
      This is my first post here -- apologies if I'm making any mistakes on protocol -- I have spent some time checking prior posts but this seemed the best place to jump in.
       
      I have a 13lb skin-on, loin attached pork belly I'm going to cook for Christmas dinner. Coincidentally I also have an Anova sous vide circulation heater and a new plastic tub with a lid.
       
      The recipes I've saw mostly call for seasoning, a water bath for 36 hours and then a deep or pan fry to crisp. Now I have the setup, and look at the combination of the roast and the container I realize I have some questions about what I'm doing -- I've attached a picture below of what we're starting off with. 
       
      Here are those questions:
       
      The fit seems a little tight to me -- is the container size fine? I was planning on seasoning, tying and double bagging it in large ziploc bringing bags ( water displacement, no vacuum sealer ). I've convinced myself the ziplock method is fine, but is standing the meat vertically in a space close to it's dimension for a 36 hour cook ok? After the 36 hours in water, it is Ok to refrigerate? The main recipe I've been using as a base calls for removing it, shocking it and then removing the liquids for sauce before deep frying -- would it be ok to shock, refrigerate for several hours, then bring to temperature in the bath again before proceeding with browning/bringing to temp? If this isn't a bad idea, how long would you keep in the water bath after refrigeration? Deep frying vs. a quick hot oven? I'll rub baking soda on this, and I'll fry if need be -- but does anyone have experience or thoughts on whether you'd be defeating the purpose of using sous vide in the first place if you just used a suitably hot oven to crisp the skin after cooking sous vide and drying the skin beforehand? I'd prefer not to to do an inside stove top fry for something this large right before dinner if it wasn't sacrificing too much.    
      Thanks for any help, would also be great to hear any other useful advice from anyone that's went through a similar process.
       
      Gary
       

    • By pmilas
      HI guys,
       
      I'm here for a bit of advice. We are building a house (in Croatia, Europe), and finally have a chance to build a kitchen as i want it
      We would like to get a professional combi oven, something like this new Rational (a bit pricey) or this UNOX (better price) so that we have a long term solution for our needs.
      The reason we are going for the professional oven is that, for example UNOX, is cheaper than "home combi ovens" from brands like Miele, Gaggenau, etc. and are much better than those.
       
      Does anyone have any experience with pro combis at home? i have only seen a couple of people, at least on the internet, that have them at home. I guess that setup would not be a problem, because we designed a water inlet and outlet for the oven, and the voltage is OK. is there anything we didnt think of? Will that oven have higher maintananace cost, even if its used only couple of days a week?
       
      Thanks for help
       
      P
  • Recently Browsing   0 members

    No registered users viewing this page.