Hmm my plates are bigger in diameter. Meh. Yeah I saw the one photo that made it look like it worked on a bigger plate but I’d like actual confirmation of this. Nice substitute for plastic wrap though. If they actually work as advertised, which of course if it is being sold in meh that is an open question.
@Larry1977 Vacuum chambers maintain a low pressure in a volume. Lower overall pressure means lower partial pressure due to moisture. So stuff will dry faster in the chamber, briefly, until the partial pressure of the water vapor reaches the same level as outside the chamber. So if you replace the air every few minutes, it should measurably dry stuff inside faster.
By measurably faster, I mean measurably with sensitive enough instruments as compared to similar stuff on an uncovered plate in still air. Using a fan to dry stuff would be faster still.
For example, get 3 identical paper towels, put them on 3 identical plates, and add 5 grams of water to each one. Record the weight of each plate with its wet paper towel. Put one plate in a vacuum dome, one plate in still air, and one direct a fan at the third one. Wait 100 seconds. Weigh the plates again, and see which plate lost the most moisture. I predict that the vacuum plate will dry faster than the plate in still air, but the plate with the fan might be even faster.
@alacrity It is approximately a 10 inch diameter suction cup, so it needs something that with a flat space that is at least 10 inches in diameter. Note that these have a relatively wide seal. The leftovers have to stay in an approximately 9 inch circle until you get the cover on. Large square plates should work, if you can get your leftovers to stay in the circle.
I’m puzzled: why are these not microwave-safe? Is there metal lurking somewhere in each dome’s innards? I ask because I use dome-like covers to place over a plate when I’m nuking something to eat. I don’t especially care about the vacuum quality of the dome, but I’m thinking that a couple of these would be useful as covers in the microwave in the way I’ve described.
@gertiestn If you put a vacuum sealed plate with leftovers into the microwave, some of the water in the food will turn to water vapor. The vacuum would become pressurized, if it could handle pressure. But, it can’t. So the steam from your leftovers will spray your leftovers around the inside of your microwave.
But wait! There’s more!
Ever have plastic get deformed in the microwave because a few drops of tomato sauce got insanely hot, before the spaghetti even got warm? If any of part of any seal gets too hot, or if the stiff part gets warped, the vacuum seal will never seal a vacuum again.
@gertiestn, Hi. I’m the one that tested the PressDome in our office.
It’s important to note that the vacuum is created by depressing the clear stretchy plastic on the top of the dome which pushes the air out the bottom.
I tested it by placing small bowl with maybe a quarter cup of water in it under the PressDome, and ran the microwave (1000 watt), for 4 minutes on high. The seal was made with the bottom of the microwave plate. After allowing it to cool fully I performed the test again.
The results were, that after fully cooling down again, the clear stretchy plastic had a little more give to it, not a whole lot, but still a noticeable difference from the control unit. While it could still create a vacuum, I was concerned that after numerous (maybe a dozen or so) uses the plastic would begin to deteriorate beyond usefulness.
While we did see that it had been marketed as microwave safe, and even the packaging mentions putting it in the microwave (not specifically saying microwave safe). We can’t recommend putting it in a microwave.
That said. It doesn’t have any metal components (so it wont explode), the vacuum was maintained throughout the cooking process, it did expand during, but quickly retracted after the cooking stopped.
All that said, I will say these are great for keeping your food longer in the refrigerator / freezer / cupboard, but reheating your food, either in the oven or microwave with the PressDome still on is isn’t advisable. I would suggest removing it, and placing a paper towel, or another plate/bowl over it.
The Amazon page for this, as well as the pages for other products serving the same function, indicates that they are microwave safe. A couple reviewers mention using in the microwave, with only one mentioning a potential issue (says can “literally hear it breaking from the heat” at microwave times never over 2 minutes l). Personally, I am willing to give it a shot at this price (of course, conscious of the need to release the vacuum pressure prior to using in the microwave).
The main complaint that some, but not all, have seems to be trouble with getting them to stay vacuum-sealed. Reviews also indicate that they are good at keeping warm things warm if you intend too use for that purpose.
I watched an infomercial for them. The person doing the demo showed the power of the vacuum by using it as a suction cup to lift something that weighed 20 pounds.
That is the sort of simple science demo that I do in class.
I figure the area under the dome is on the order of 50 square inches, so lifting a 20 pound weight takes left than half of one PSI.
The main advantages of these devices is that they are clear, so I can use a small balloon as a pressure indicator, they are wimpy and aren’t made of glass, and they can be child powered. You can’t use a glass vacuum dome because glass breaks. You don’t want to create a serious vacuum, because bad things can happen.
“PressDome Professional Line products have a stainless steel vacuum pump and are not designed for use in the microwave oven. Meh’s PressDome offer looks like the ones seen on TV that are microwave safe; First release the vacuum pump by pulling up.” http://tvstuffonline.com/press-dome/
has more helpful info, such as, use PressDome with plates, platters, skillets, bowls, cutting boards, counter-tops…
Would keep my brownies and lemonbars 3x fresher. I do not like nor consume most leftover foods. But, hey! What would salads, cut fruit, cooked seafood, a sandwich? or pizza taste like if saved in an environment without air? My wine that is saved a week+ after removing the air is as tasty as the day it was uncorked. Excuse me. I want to go buy and try these out. Four of these PressDomes are selling here for only $15! That’s a GREAT SAVINGS! ttyl ya’all
So let’s see if I have this straight - you go to a restaurant, order your meal, eat only part of it. You then scrape the remaining food into a paper or foam container, take it home, scrape the food out of the container on to a plate, then cover it with one of these domes. Have I missed something? Or do you frequent restaurants that include the serving plate with the meal, to take home with you?
Preparing all your own meals is usually cheaper, but you also sacrifice the time it takes to prepare it, almost always introduce more waste, and are limited by both your cooking abilities/equipment and the logistics of getting and maintaining ingredients.
I live in a great place for good, cheap, fresh food (Portland, OR) and work from home, so I may be a bit of an outlier. After comparing bills for a month with some friends, they spent nearly as much as I do on food during the given month while preparing the large majority of their meals. Granted, they eat well.
I’ll happily pay the small amount of extra cash to be able to eat whatever fresh, expertly-prepared food sounds good that night and do better/more enjoyable things with my saved time. Good on you if you enjoy cooking every night, but it’s a chore for me to make anything in the kitchen that isn’t coffee.