I once heard (I believe on Flatow’s Science Friday) a discussion of the possibility, via the use of plastics & light, of creating a freezer which can work as instantaneously as a microwave.
However, wouldn’t a VacuumBox be more efficient, insofar as saving on the expense of electricity and repair bills, not to mention environmental concerns?
So… if vacuum-packing has been invented long ago, why not personal Vaccum Boxes, as a better alternative for keeping food fresh? Have Great Minds ever mulled the possibility?
Translation: a vacuum alone isn’t an instant freezer. Heat energy would have to be actively removed from your Swanson’s frozen dinner by some other method; otherwise, it’d just retain the heat it had when it entered the vacuum (or, more precisely, reach a kind of stasis with the environment outside the vacuum, with which it would still trade radiative and conductive heat, unless you’ve figured out a method of making your SFD float and utterly isolated it from radiative heat, in which case you have something much handier than an instant freezer).
Vacuums are a good way of keeping food fresh, though, which is why you see so many infomercials for the FoodSaver and the like. Problem is…well, let’s take cheese. If we had a ‘vacuum box’, a box that creates a vacuum every time you shut the door, the block of cheese you put in it will still lose moisture from its surface unless you’ve wrapped it tightly, even in the vacuum. Then, you got nasty gross crusty cheese. So, the point of the box is lost; you’re better off sealing it in tight vacuum plastic.
There’s a vacuum thingy on TV, maybe Ron Popiel of Pocket Fisherman fame. In combination with cold, it works miracles. I never could stand the infomercial format long enough to get really informed, but I do recall it would solve a lot of problems for $200-300.
Wouldn’t a vacuum box negate the need for frozen dinners? AAnother thought: (especially if it means savings on electric bills) I think people could more readily survive without ice cream, popsicles & cold drinks, than without a basic means for keeping food fresh. I personally can live without ice cream, and lately it’s been my habit to stick to powdered drinks such as ice-tea to which I add ROOM-TEMP water, since that’s better for my digestion than cold drinks.
As for the cheese problems, perhaps that too can be solved by “great minds”? In any case, if you mean hard cheese, that too is quite unhealthy, & people who want to save on the high cost of running a frig can live without it. I know I can, and that if there were such an invention as a vacuum box I’d rush to buy it, living HAPPILY without cold stuff and without cheese. Perhaps I’m an anachronistic throwback, or an anarchistic revolutionary… whatever. Oh, & one more thought:
A vacuum box would be a great backup system for people who periodically don’t have enough room in the freezer, or else whose refrigerators go on the blink.
Re: Foodsaver, fine & good, however I realize that my OP didn’t spell things out clearly. What I meant was a vacuum-box that would be like a frig (i.e. you open the door & take stuff out, and as soon as you shut the door a vacuum sucks out the air.) I wonder whether the guys at FoodSaver considered designing such a toy?
It’s not the vacuum that preserves the food. The vacuum merely prevents the infiltration of microbes. For your vacuum box to work, you would not only have to evacuate the air, you would also need to kill all of the micro-organisms that were present - most of which would easily survive any partial vacuum you could reasonably apply to your box… in short, it wouldn’t work.
Plus, you would have no ice to make frozen Margaritas! What kind of life would that be?
That’s the whole challenge… for someone to invent a vacuum box that would thoroughly suck out air (not just partially). As for ice, I already discussed the matter above (i.e. cold stuff)
just thought of something else, & of course it may all amount to science fiction, but then again two decades ago the Internet was also science fiction:
In my OP I mentioned that a scientist on Flatow’s radio program discussed that he’s working on making a microwave version of a freezer, via plastics & light. That ought to solve the need for cold & frozen stuff. So, instead of using the term VacuumBox, let me re-phrase it:
VacCool-Box, namely a machine which would have
one compartment consisting of vacuum-storage,
and the other consisting of [the potential invention of] an instant frig/freezer (for example, 1/2 min. to cool drinks, and 2 min. to freeze drinks). That still doesn’t solve ice-cream (& cheese) but, hey, you want clogged arteries?
Quite a challenge, that. I know of no technology that can create an ideal vacuum - it would certainly be much more expensive than conventional freezer technology. The other problem, here, is that if you were able to get that kind of vacuum, the walls of your vacuum box would have to be about 4 meters thick (just a wild guess, but you get my point).
All of this is still irrelevant, because you would still have to find a way to sterilize your food products every time you opened the door. As I said, many micro organisms can survive in a vacuum.
I’m not sure what would happen, structurally to food products in zero pressure. The cellular structure might be disrupted to the point where you wouldn’t want to eat it.
Yikes! Pulling a substantial vacuum on food would render it unpalatable if not unidentifiable. Imagine all of the water in the food (and there is lots, even in dehydrated foods) boiling off under vacuum. The result would be the hardest, dryest, nastiest stuff you ever ate. Once the fruit exploded, and the milk boiled off the pot roast would end up like formed Kool-Aid.
The devices shown on TV remove a sizeable prtion of the air around food, but get nowhere near anything resmbling a vacuum. At best they would prevent bread from going stale or moist foods from drying out. A platic bag and a twist-tie can do the same thing (ah, Tupperware®)
As for the design of a vacuum-box. The walls would not need to be very thick, just designed as a pressure vessel. A cylinder works well. The issue of power consumption, however, was not addressed. If you think your frig runs up your electric bill, trying powering a series of mechanical and diffusion pumps every time you crack open the door.
There is an application for vacuum in a frig…as insulation. In lieu of fiberglas®, plans are underway to construct structural vacuum panels (just like a thermos) which would make the frig much more thermally efficient.
One could, I suppose, use a vacuum pump to “boil off” refridgerant in the cooling coils of the frig to draw the heat out of the box, but compressible fluids and natural expansion seem to be working just fine.
Should we touch on ammonia cycle refridgerators?..perhaps another day.
This is incorrect. Even in a vacuum, there is radiation, and so there is temperature. A thermometer in a vacuum inside a box in a room at 70 degrees will register 70 degrees once it reaches equilibrium. It will reach equilibrium through radiative heating or cooling from whatever temperature it was at when it was placed in the box.
Interesting! OK, I surrender, but who knows, maybe someday someone will invent another way of keeping food fresh/cold, that doesn’t consume so much power. For example caves can keep stuff very cold, so maybe they can be simulated for household use… Just kidding.
