At the risk of looking like a kitchen idiot

May 25, 2009 9:04 PM

How can I take care that when I'm reheating glass jars of frozen sauce (or any food) on the stove, they won't shatter?

I won't finish a whole jar of pasta sauce (or anything jarred) at once, and I need to freeze it if I won't eat the rest within a week. If I am planning ahead, I can take out the sauce in the morning to thaw to room temperature by evening, and then the sauce can be removed and reheated in another container.

Often I am not that together, so I want to thaw out a frozen jar of pasta sauce ASAP. The last time I tried this with a microwave, the glass shattered. The jar broke in half after I had taken it out of the microwave, set it on a cool surface, and turned my back. This must have happened due to a rapid temperature change that the ordinary glass wasn't made to handle. I have been wary of trying it since.

These days I don't have a microwave. The old way that I learned to heat up a frozen jar is to set the jar in a saucepan half full of cool water, then heat the water to boiling until the sauce is thawed out enough to decant into another saucepan and heat up alone. Is this Generally Recognized As Safe?

posted by Countess Elena to food & drink (25 comments total)

Just put it in the sink, closed, and run hot water over it until it defrosts. This works for meat too, by the way, as long as it's still shrinkwrapped.
posted by nasreddin at 9:09 PM on May 25

I'm surprised that you're putting the glass jars into the freezer. When you don't use an entire jar, just put it into a plastic container and freeze that. When you take the container out, you can squeeze alternate sides a few times and drop the large ice-chunk right into a bowl to microwave or into a pot to warm on the stove. That way you don't have to worry about the jar bursting in the freezer, either (something that has happened to me).

Glass and sudden changes in temperature really aren't a good combination - even Pyrex has its limits. Just make a habit of storing leftovers in plastic before putting them in the freezer.
posted by Miko at 9:17 PM on May 25 [8 favorites]

Glass jars aren't really safe for freezing, either. I think the real answer to your question is to get some plastic freezer containers. When you use part of a jar of sauce and want to freeze the rest, put it in a plastic container and freeze that.
posted by Chocolate Pickle at 9:18 PM on May 25

Plastic containers are a double win, because you can buy ones which are microwave safe.
posted by Chocolate Pickle at 9:19 PM on May 25

run hot water over it until it defrosts

Don't do this. Total waste of water and energy. Just submerge the jar in a sinkful of cold water.
posted by monospace at 9:21 PM on May 25 [6 favorites]

Yeah, what miko said. Ziploc (or equivalent) freezer bags are perfect for this.
posted by dersins at 9:22 PM on May 25

Yeah, it never would have occurred to me to freeze glass jars. This is what Tupperware was made for!
posted by showbiz_liz at 9:28 PM on May 25

frankly i've given up on any sort of rigid container. mrs chasles and i started using ziplock bags years ago and haven't looked back. whatever is left over goes into a sandwich size zipper bag and is ready to reheat next time. far less food wast and far more practical storage. as far as reheating, pop it out of the bag frozen like a Popsicle and chunk it in the saucepan on low with a couple tablespoons of water. fire and low and lid and you're right as rain.


-c
posted by chasles at 9:48 PM on May 25

Just submerge the jar in a sinkful of cold water.

Yeah, it sounds counterproductive, but cold water seems to defrost frozen things quicker. I freeze chicken breasts in freezer bags, and defrost them in cold water, it's super quick (1 hourish). When I used to do it in warm/hot water, it took foreverrrr and I was apparently breeding nasty stuff by keeping the outer part of it warm while I waited for the inner part to catch up. If you have frozen jars currently, they should be defrosted in cold water. Or defrosted enough to dump the whole mess into a saucepan to warm up.

Going forward, +1 for tupperware/gladware/whateverware for sauce. run it under warm water to dislodge it from it's container, and warm it up in a saucepan. 10 minutes, tops, and no shattered glass. Or plastic bags like chasles describes, if you don't have a lot of it.
posted by AlisonM at 9:55 PM on May 25 [1 favorite]

What I've found works well is to use muffin trays/tins, fill them with sauce, stick it/them in the freezer. Once frozen, pop them out into a ziploc, label it if necessary (i.e. if you store spaghetti sauce and pizza sauce) place the filled ziploc into the freezer. It lets you conveniently choose how much you need, while keeping the rest of the 'sauce muffins' frozen. To thaw, toss it/them in a saucepan/microwave, possibly with a tad of water.
posted by hungrysquirrels at 10:05 PM on May 25 [1 favorite]

Stop using glass jars. Start using plastic containers that are labeled something like "freezer safe". Then, when you forget to de-frost, put the container in the sink with warm water just until the mass of frozen sauce loosens from the container edges. Then dump the block of sauce into a saucepan, and heat it very slowly until it melts. Or, just eat something else, and have the frozen sauce tomorrow.
posted by Kololo at 10:18 PM on May 25

Yeah, it sounds counterproductive, but cold water seems to defrost frozen things quicker.

The key word here is 'seems'.

Anyway: nth "don't freeze glass jars".
posted by pompomtom at 11:03 PM on May 25 [1 favorite]

Another "zip-loc" vote.

Yeah, it's wasteful, but so is throwing out a lot of food.

And you can pre-portion them into single servings, making the thaw-out easier since you only need to take out what you're going to use.

You can also use something like a dish rack/toast rack, whatever to separate multiple portions in one bag. (Put two portions in one bag, lay it over a divider and squish it around until you have equal sides on both sides, freeze in position.) For more viscus things, like ground beef, you can divide it in the bag with a chopstick, or form patties/meatballs/whatever ahead of time and freeze.

Or plastic containers if you want to be more environmentally friendly, but its harder to divide stuff up and you get freezer burn faster.

To get the air out of a bag before sealing mostly submerge it in a bucket/pot/whatever of (cold) water, then seal it. The water pressure will push the air out and keep stuff from drying out so badly in the freezer. Just be careful not to get water inside the bag.

And date 'em with a sharpie.
posted by Ookseer at 11:14 PM on May 25

Hmmm, I always freeze sauce in mason jars. 8 min on defrost in the microwave seems to thaw things out without a lot of rapid temp changing issues. No problems in 10 years (so far!)
posted by Aquaman at 12:00 AM on May 26

two quick points about cold water & sinks:

- empty the sink & refill it once or twice during the process to speed things up, as the water will cool down as it thaws the frozen food.

- it works great in reverse, too, ie to cool warm food prior to putting it in the fridge or freezer.
posted by UbuRoivas at 12:09 AM on May 26

You don't even have to fill the whole sink with water. You can fill a basin or a large pot instead.
posted by Majorita at 12:59 AM on May 26

Doing it on the stove top should be fine. You use water because it will have a close-to-uniform temperature gradient and heat the glass jar evenly.
posted by grobstein at 1:11 AM on May 26

I like using glass jars. It works to just put them in a bowl of slightly warm water and go change your clothes or something--it doesn't need to fully defrost, just enough so you can slide it into a pan and put it on the stove to defrost the rest of the way. If you're reusing jars, it helps if they're wide neck ones like Classico spaghetti jars or regular mason jars. I keep those around for storage. Also Marie's salad dressing jars. Those things are perfect.
posted by A Terrible Llama at 2:10 AM on May 26

+1 for zip-loc™ bags, which you can get in several sizes. I even use the gallon-size ones for a lot of non-freezer stuff, like marinating meat (if you push out the air, you get near-perfect coverage), preparing ceviche, or making salsa.

As for the waste of throwing them out: as a child of immigrant parents, I'm both pround and a little embarrassed to announce that my mother washes them and reuses them. I don't think you should reuse them if you've been marinating raw meat in there (plastic tends to be lipophilic and is hard to clean without full sterilization), but certainly you can wash the remaining pasta sauce out of the bag and let it dry inside-out.
posted by LMGM at 3:13 AM on May 26 [2 favorites]

Tupperware or pyrex. Inexpensive, reusable, and at the end of their very long days, recyclable.
posted by Augenblick at 5:10 AM on May 26 [1 favorite]

The old way that I learned to heat up a frozen jar is to set the jar in a saucepan half full of cool water, then heat the water to boiling until the sauce is thawed out enough to decant into another saucepan and heat up alone. Is this Generally Recognized As Safe?

Folks, he doesn't use a microwave! Yes, that method is Generally Recognized As Safe. You don't have a microwave and this method heats them up gradually enough. It's safer than microwave popcorn.
posted by bigmusic at 5:18 AM on May 26

National Center for Home Food Preservation says:

Freezing FAQs: Packaging Materials

Personally, I would advise against using plastic (tupperware, ziploc, etc) because of the health risks. Who knows what synthetic (carcinogens, estrogen mimics...) chemicals could leaching into your food? Glass does not have this problem, plus it is reusable, so there is no waste.
posted by bengarland at 5:53 AM on May 26

Mason jars intended for home canning are tempered to withstand wide variations in temperature, kind of like Pyrex. If you must use glass in the freezer, try mason jars (not your everyday leftover packaging jars), and make sure to leave ample headspace to allow for the liquid to expand when it freezes.
posted by libraryhead at 6:30 AM on May 26

Yeah, it sounds counterproductive, but cold water seems to defrost frozen things quicker.

The key word here is 'seems'.

Just to add, the reason submerging the object to be thawed into liquid thaws it so quickly is that the liquid is so much more dense than air that the transfer of heat between the liquid and the frozen object happens so much faster. Thus equilibrium is achieved quicker than in the case where it is just mostly air hitting the object. To speed things up further is intoduce a convection current to the liquid. even just a little bit of movement of the liquid around a frozen object will further more increase the abililty of the liquid and frozen object to reach equilibrium. This is why speed thaws of frozen foods often call for submerging the item and introducing a slow drip of water from the tap to move the water around a bit.

Lastly, submerging in the frozen object in hot water and introducing a hot drip of water to the party will cause the item to thaw even faster but you don't want to do that because a.) it has the potential to start cooking the item and b.) it raises the chance that bacteria might grow in the food.
posted by mmascolino at 7:48 AM on May 26 [2 favorites]

Just piling on here.

1. Run water over the jar to thaw,
2. Don't freeze glass in the first place,
3. Use smaller plastic containers to freeze single-serve portions for yourself.

I like to take small portions that I've frozen, and seal them up in a vacuum-pack so they take up less space, and don't freezer-burn.
posted by Citrus at 10:19 AM on May 26