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1) Sealing wet ingredients

For sous vide, you generally want to get out as much air as possible. With dry ingredients, this is easy. But with wet ingredients, it's more difficult to get all the air out and still get a good seal. You'll find that if you just go into it as you would with dry ingredients, the moisture will quickly get sucked up into the catch tray. First lesson: it doesn't matter if some liquid gets sucked into the catch tray. That's what the catch tray is there for! Unless every drop of the liquid is precious, it just doesn't matter. And even if you are sealing truffle juice or something, as long as you clean the catch tray whenever something gets in it, you can simply pour any excess back into some other receptacle for other uses.

So, now that I've said that it's no problem for the moisture to leak into the catch tray, let me tell you what is a problem: if there is moisture between the bag layers, then the sealing strip will have trouble forming a good seal. Note that I didn't say "can't form a good seal." It has trouble. So, lesson two: when working with ingredients with some moisture content, always use the highest sealing level ("5" on my model). The greater heat and time for the seal makes it more likely that you will get a good seal, even if there is some moisture between the layers.

However, you don't have to leave it up to chance and hope that the seal works. Here are several ways I've found to minimize the moisture that gets under the sealing strip.

The first is most obvious. Seal just before (or as soon as) the moisture creeps up to the sealing strip. This way, there is less moisture around for the sealing strip to have to seal through. If you go a tenth of a second too long, it's usually no big deal. If you go three seconds too long, you've usually got a ton of moisture in there, and it usually won't seal. Vacuum-packing wet ingredients is not a "set it and forget it" job. It only takes a few seconds, but you have to do it manually. The automatic sealing settings will not work for wet ingredients.

Another trick is that, depending on what you're vacuum-sealing, you can roll up a paper towel and stick it in the bag between the product and sealer. The paper towel will compress immediately and act as a barrier between moisture and the sealing strip. Obviously, you might not want a paper towel in there with all of your products. But, for instance, for something like a roulade, you usually wrap it up in plastic wrap before vacuum-sealing it, anyway. Here's a photo of what I mean (also at right).

If it's something with a lot of moisture, it often won't work to lay the bag in front of the FoodSaver with the FoodSaver on a counter or table, because laying the bag sideways will make tons of liquid spill out before you even get to the part where you fiddle with the FoodSaver to get it open, then get the bag end in the vacuum tray, then shut the lid, etc. But here's the thing: if your bag is too full of liquid to lay it sideways, just move the FoodSaver to the end of the counter, as shown here (also at left). That way, the bag can dangle off the edge. Gravity is your friend. Gravity will, obviously, keep the bag from spilling, but gravity will also help the liquid fight the vacuum. Recall that liquids are much more dense than gases, and gravity therefore acts more strongly on the liquids. So positioning the bag upright while it's sealing makes the liquid relatively less apt to travel up the bag into the sealer than the gas. If my physics are wrong here, correct me please, Christy.

The other thing this bag positioning allows you to do is to fold the bag. Folding the bag can't be air tight, obviously, or else the sealer can't suck the air out. But for some physics reason that I don't know (are gas molecules smaller?), gas will escape through a smaller space than a liquid. So folding tightly, as shown here (also at right) helps keep the liquid in.

The trouble is how to hold up the bag while still having a free hand to operate the machine. If you've got a bag with heavy stuff in it (as when you're brining something), the clamp of the machine won't hold it up safely. Here's what I do: use a knee. You hold up the bag using one hand and one knee, then operate the machine with the other hand. Here's a picture of me doing the folded-bag-knee-assist technique (also at left).

2) Have a backup plan for sous vide: seal multiple times

I had a couple early experiences with moist items where I thought I had a good seal, only to have the bag come open during the cooking process. Specifically, what happened, both times, was that the bag stayed sealed until I picked up the bag out of the water to manipulate its contents while hot. The pressure from me (gently) squeezing the bags, the gravity of the items in the bag, combined with the heat from the water bath, and the relatively weak seal to start with (because the items were moist and I wasn't as skilled at sealing moist items then) made part of the seal come undone.

So, given the ease of sealing the bags multiple times, and the huge hassle if a bag ruptures, I always make multiple seals on bags I'm planning to cook. If I'm only vacuuming something for storage, I'll only do a single seal (unless it's particularly wet and would create a mess in the fridge if it ruptures). But for cooking, I usually do two seals for dry contents, and three for wet. Sometimes even more if I'm not positive I've gotten a good seal.

I always make the first seal with the end of the bag toward the back of the vacuum chamber area. That way I have more room to make future seals if necessary. With wet ingredients, you may not be positive that you've gotten a good seal, even if it initially holds and no air appears to get in. When that happens, if there's already moisture above the first seal, take a paper towel and dry inside it. Then just move the bag down a bit and re-seal. You don't even need to vacuum again if no air has visibly gotten in, just flatten the bag top and seal. If, on the other hand, you can see that air has gotten in, do the same thing, paper toweling any moisture above the first seal, then re-vacuum and seal once you've moved it down. Because most of the bag length will be sealed even if there are a few leaks, you'll be less likely to get moisture up into the sealing strip the second time.

With both wet and dry ingredients, after you've gotten a seal that you're sure is good, then move the bag down and re-seal again. As with before, use a paper towel to dry out the inside of the bag above the good seal before doing your backup seal. I have seen, once or twice when cooking bags with a lot of moisture, liquid has visibly escaped the first seal but the later seals have held. As I said, I usually do two backup seals after I get one good seal if I'm cooking wet ingredients. With dry ingredients, I do one backup seal.

3) Quit lining things with plastic wrap. Just vacuum seal the entire mold.

The thing is, vacuum bag material is really stretchy. In the case of the FoodSaver brand bags and rolls, one side is clear and the other has a cross-hatch pattern on it. The clear side is stretchier, so you want that to be on the side that will have to deform more (i.e. the side that will be sucking down into the mold). So it's perfect for lining, e.g. terrine molds, or containers into which you're pouring a gel to set. Why use a springform pan, when you can use a regular (airtight, watertight) pan that has been vacuum sealed? When it's done, you just cut around the bag, and lift the entire thing out. Here's a picture of a sealed mold (also at left).

This is sooooo much quicker, more efficient, and far better-quality. Plastic wrap always wrinkles, sticks to itself, etc. I got this idea from Ideas In Food, but they never posted it on their blog. They figured it out at one of their classes. I went to a two-hour demo class on Activa (and one on methylcellulose), and while making a terrine they mentioned that they just discovered that they could vacuum the entire mold. That was easily the single most useful thing to come out of those classes (not that there wasn't lots of other great stuff, this is just so amazing).

See here (also at right) a mini-baking dish that I used as a terrine mold for a chicken thigh terrine, topped with chicken skin. I vacuumed the entire thing, then put in the chicken and topped with the skin, then vacuumed the entire thing again. Then I cooked it sous vide at 150F for three hours. Then I chilled it. Whenever I'm ready to cook it, I'll cut through the bag, and lift out the entire thing. Then I'll saute it to warm it through and crisp up the skin. Then I'l trim it into a nice plan, and plate it.

And see here (and at left) a crustless cheese cake I made. I vacuum-sealed a loaf pan (picture here), then poured in the cheese cake batter. Even though I was planning on baking it in a bain-marie (hot water bath) for more even cooking, I was afraid the bag might not hold up to the oven heat (particularly the parts of the bag that would be out of the water). So I covered the exposed edges of the pan with foil (picture here). It worked splendidly, so I tried it with some smaller mini-cheesecakes without the foil. It worked fine! The entire bag seals in the oven (i.e. not just the sealing strip), but once you cut in next to the mold, it all comes apart easily. You don't want to do this in a hot oven, but at 325F for thirty minutes or so, it was fine. I'm gonna post about this cheese cake soon. It was good.

4) You can seal anything to keep it fresh.

This might seem obvious, as it's seemingly the sole feature for which they market vacuum sealers. But in addition to the normal things you'd think of vacuum-sealing--and taking into account the previous point about sealing entire molds and such--you can also seal things like entire half-used cans of tomato paste or tahini, and entire half-eaten containers of ice cream, and entire tupperware containers full of leftovers.

You want the bag or roll material to suck and stretch down into the can or tupperware or other container. You want it touching the food, so that there's no air there. It'll make things freeze much better, without creating ice crystals. It'll keep ice cream, for instance, much more fresh and crystal-less. So, remembering the point about the stretchy side of the rolls and bags, and make sure the stretchy side is on the top of the container.

You don't need to buy FoodSaver branded tupperware with goofy little valves on top. Just toss the food in the container, toss the entire container, with no lid, into a vacuum bag, and then vacuum seal it. The walls of the container will keep the food and, as mentioned above, the moisture from leaving the container and traveling up the bag.

Note, however, that if you're sealing something that is large relative to the bag size, that the power of the vacuum tends to pull so stongly that it sometimes pulls part of the bag right out of the clamp. Then the part of the bag on the sealing strip tends to be wrinkly, or wadded up. That results in a poor seal. So I find it quite helpful when vacuum-packing oddly shaped items in bags just big enough to fit them, to hold the edges of the bag as it is vacuuming (obviously much easier if you use the automatic setting, which is perfectly fine for half-used cans and such). As you're holding the two edges of the bag, pull out toward the sides as shown here (and at right).

Thanks so much for this post. And yes, I'm still blogging on the anonymous DL. You've given me a lot of useful information here, but I may still have some FoodSaver problems.

My most serious potential problem is that I fear my machine's sealer may be defective because even sealing dry ingredients has been hit or miss for me. A few days ago, for example, I sealed some Brussels sprouts just to keep them fresh because I knew I wouldn't be using them for a few days. For the first two days the seal seemed fine . . . but in reality the bag had a slow leak somewhere and the sprouts were no longer vacuum sealed by day three.

This serious problem, however, may be a blessing in disguise . . . because I think I need a different FoodSaver machine to use your multiple-seal technique for my sous vide efforts. And if my machine is broken, I'll likely have an easier time returning it to FoodSaver. I currently have the V3840.

It sounds like your machine has a manual clamp, engagement of which is separate from the activation of the vacuum and sealing processes. Mine, by contrast, has an "automatic bag detector" that triggers the process. I stick my bag in the slot and the machine senses it, then begins the vacuuming and sealing processes. I can set it to seal without vacuuming (which is intended for the first seal when making bags from roll material) and I can interrupt the vacuuming at any time to start the sealing process, but I don't have any control over the location of the seal. I don't think my machine will make a seal unless the bag is inserted into the slot to the precise depth necessary to trigger the sensor. And there's no clamping mechanism on my machine separate from the sealing mechanism. The only time the machine is holding the bag is when it's actively sealing it . . . then it releases it automatically. And, finally, there are no separate seal strength settings on my machine. (You mention setting the machine on "5" when sealing wet ingredients.)

Is it the case with your machine that you can clamp the bag into the machine anywhere you want and then vacuum and seal or just seal, as you wish? Actually, I think I've just answered my own questions, in part, by checking out the FoodSaver Web site and noticing that your model allows "repetitive seals," while mine does not.

So yeah, thanks for the post. I think I need to return my machine and upgrade to the one you have.

Posted by: Food Rockz Man at February 2, 2009 7:38 AM

So, first of all, are you sure the seal was bad on the brussels sprouts? Vacuum-sealing fresh fruits and vegetables often doesn't work very well because they give off sometimes significant quantities of gases as they age. Best to let those gases escape into the ambient air rather than trap them with the product. But maybe it was a bum seal.

But also, yes, you have the wrong model. You really need to get one of the FoodSavers with the "Pulse" function. That's what lets you manually control the sealing. You press the "Pulse" button and the machine clamps down on the bag. Then you press and hold the "Pulse" button again and the vacuum will run as long as it's held down. When you release the button, nothing happens. It just holds the vacuum and stays clamped down. Then you can pulse more, or hit the "Seal" button to finish the job (or "Cancel" to cancel and release the bag). The V3860 is basically the same model as yours, but with Pulse (which costs an extra $90!).

But on the other hand, I really think you'd be better off, for these applications, with one of the older, non-upright versions. I thought hard about the compact footprint of an upright, but decided on the other style because of the more manual operation. I am now absolutely positive that it was the right decision. The clamp style (which your model is not) lets you open up the machine and actually see exactly where you are placing the bag in relation to the vacuum chamber, liquid catch tray, and sealing strip.

The "repetitive seal" function actually just refers to the ability of my model to seal repetitively many times without overheating. Some people complain about the normal consumer models overheating if you try to seal five or six things in a row. I can't really comment. Mine has never overheated, but I've never sealed a whole bunch of things rapidly.

Anyway, FoodSaver is not good about providing information about the vacuum power and speed for their various models. I had to call and ask a lot of questions and have the person on the other end go ask other people questions. It turns out that the GameSaver models have a more powerful motor than the consumer models (at least that's what I was told). The GameSaver Pro Plus has one of those motors. The GameSaver Turbo Plus has two of them, which both engage during normal sealing. That makes vacuuming faster and more powerful. With that extra information, I splurged on the quite expensive GameSaver Turbo Plus. I think it's a great product.

Posted by: Barzelay at February 2, 2009 12:06 PM

test (website says I can't post because my text is wrong)

Posted by: lsmsrbls at February 3, 2009 10:07 AM

I'm not entirely sure why folding the bag over lets the gas leave more easily than the liquid, but it's not related to molecule size (or not primarily...I suppose it could have some effect). My hypothesis would be that the there's a pressure drop behind the fold (think of still water running deep, then getting shallow and going quickly--this would be the fold--and then getting deep and slow again...the pressure is lower at this deep point than it would be overall were the same flow at constant depth). Then you'd essentially be turning down the vacuum so that it's not strong enough to suck up the heavy liquid so easily, as well as providing a geometric obstacle should droplets of liquid get pulled up...not that I know whether liquid droplets come up and hit the fold at all.

I'm not sure, though. You should probably ask a real engineer. : )

Posted by: lsmsrbls at February 3, 2009 10:08 AM

Thanks for the heads-up on the gas release issue. That hadn't occurred to me. It may or may not have been the problem with the Brussels sprouts . . . but I've had the same thing happen with a variety of foods . . . the chicken bones I store in my freezer, for example, for my once-a-month stock making. So I think my machine may be defective. At any rate, I'm going to take advantage of FoodSaver's 30-day return policy and upgrade to the machine you're using. Thanks for the tips.

Posted by: Food Rockz Man at February 4, 2009 8:49 AM

So I followed your lead and upgraded to a Game Saver Turbo Plus. It arrived yesterday and I think it's defective right out of the box. The mechanism that opens and closes the lid isn't working properly . . . sometimes the locked lid is released after the sealing process is complete, but more often the lid stays locked and I need to unplug and then replug the machine, sometimes more than once, in order to get the lid to release. This happens with both the vacuum/seal process and with the seal only process. Does this ever happen with your machine? Also, a handful of times the machine has stopped mid-process and the three green lights began to blink, with the lid staying locked. Again, I haven't been able to figure out how to open the lid without unplugging and then restarting the machine. I don't know if I'm just an idiot or if I've received another piece of shit FoodSaver machine. I called customer service and the woman I spoke to was useless. Any advice for me before I pack it up and send it back?

Posted by: Food Rockz Man at February 18, 2009 5:38 AM

Mine has never done anything like that. You should definitely send it back.

Posted by: Barzelay at February 18, 2009 7:52 AM

can you tell me anything about the use of methylcellulose. i bought some and wanted to make solid sauces that melt on the plate but it doesn't seem like it can actually do that. i have tried doubling the dosage recommended by the company i got it from and it seems to just make the sauce starchy and slightly thicker. any info would be appreciated

Posted by: phillip at March 4, 2009 10:07 PM

Phillip, for methylcellulose, use Linda's primer as a resource. If you're not getting the thickening when hot effect at all, then you probably haven't properly hydrated the methylcellulose. For methylcellulose, you have to shear it into your base with a blender (run it for a long time), and then in order for it to hydrate the mixture has to get very cold. Once it has gotten cold, the methylcellulose will have hydrated, and you'll be able to use it in your applications.

For recipes, check out Martin Lersch's great resource, Texture.

Posted by: Barzelay at March 10, 2009 3:48 PM

Great set of suggestions!

I have the FoodSaver Professional III, which tends to have the same problem with the lock mechanism. You have press down on the lid, sometimes rather hard, to get the vacuum to advance sufficiently to seal automatically. Once it does, and seals, the lid will open OK.

I can't tell from the photo where you are sealing with the folded technique. Are you sealing the fold itself, above the fold, or below the fold?

One trick you didn't mention is to freeze liquid (olive oil, etc.) before adding it to the bag.

Posted by: Robert Jueneman at June 7, 2009 11:10 AM

We recently launched a website offering vacuum sealers and bags. Our channel vaccum bags are FoodSaver compatible at a fraction of the price.

We are offering a 10% discount on the sous vide bags is the discount code - SOUSVIDE is used. Enjoy!

www.vacnbags.com

Posted by: Vac-N-Bags at July 24, 2009 1:16 PM

I just purchased the GameSaver Turbo Plus, and I have noticed a slight loss of vacuum between when you release the pulse button and press the seal button. It's not a lot, but most of any compression capability is certainly lost when this happens. Also, I have yet to get a "true" vacuum seal. It's quite possible my expectations are not consistent with what the product can really do, but is this normal or do I have a defective unit?

Posted by: Jerry at August 16, 2009 8:59 PM

Jerry, I've experienced that, but only slightly. It's usually only noticeable when sealing liquids. Once the air gets sucked out all the way (and the liquid starts creeping up the bag) it will no longer let air back in. Even before that, it's more like a slow leak until you press the "Seal" button. It's imperfect, but it's manageable.

And by the way, that really has nothing to do with "compression." However, none of the FoodSaver sealers is going to be able to do compression, because they're just not powerful enough.

Posted by: Barzelay at August 16, 2009 11:24 PM

Hi all together, for more than 5 years I had a vacuum-sealer with only 1 sealing - now, I use a lava vacuum sealer from germany, a high quality vacuum sealer that has 3 sealings (weldings) in one time. no more problems with not well welded sealings. and also, you can minimize the vacuum with a pressure gauge, especially for soft products. you can buy the lava vacuum sealers in europe at www.lava-vacuum-packing.com

Posted by: Vakuumverpackungsmaschine at August 30, 2009 6:46 AM

The tips about sealing liquids with a foodsaver are awesome. Thanks a lot. Inspired by your gravity point, I realized you can make the sealing foolproof: you just need to make a bag that's 18-24 longer than you need (I suppose it would depend on how strong your vacuum pump is; I have a V3825; with your super strong game saver you might need longer), and then put the foodsaver at the edge of the counter and put the bag vertically below it like you describe. The pump is strong enough to pump all the air out but not strong enough to pull water up 18 inches. You don't need to finesse the Pulse Vac or crimp the bag or anything; the default automatic setting works fine (because the liquid never gets close to the sealer).  It's awesome: I can make any recipe from Under Pressure etc without dropping $2k on a chamber vac. I've even sealed a bag of just water to show I could.

Posted by: Scott Hansma at November 7, 2009 8:56 PM

I am in love with vacuum sealing anything and everything. It is so much healthier than buying pre-packaged food. I use it mostly for veggies and mini-meals. I found a trendy new website that sells the bags for 50% discount. I have used them several times and no problems. The site is www.thevakshack.com

Posted by: Amanda at March 23, 2010 1:14 PM

Do you know if the FoodSaver Pro III Plus is the same unit as the GameSaver Turbo Plus? The Pro III Plus looks identical and seems to have the same features listed as the GS Turbo Plus.

p.s. I was in a bind (ordered a gamesaver turbo plus per your recommendation, but the company failed to ship it in time then told us the last unit they had was broken.. this was a couple days before our event!) and bought one of the low end manual units from Target for 79.99. It actually worked great! I was able to sous-vide a few different items successfully. But even so, I was very cautious about repetitive seals and let the unit rest for 3-5 minutes between vacuums.

Posted by: Jabu at December 16, 2010 8:11 PM

p.p.s. The cheap one doesn't have a pulse feature, but if you just make the bag long enough and use the other tricks you outlined, not much liquid will get sucked through. Then you just use a paper towel to dry out the exposed cavity as best you can and throw down another two seals above the first one. I honestly was really tempted to just stick with the $80 unit.. but I know every time I used it I would be scared the weaker pump would crap out on me.

Posted by: Jabu at December 16, 2010 8:49 PM

Hi all , my old vacuum-sealer had only 1 sealing. Now i have a vacuum sealer with 3 sealings in one time. I have no more problems with not well welded sealings. Great!

Posted by: Vakuumtuete at May 10, 2011 11:27 AM