I have a small pot that I use pretty frequently for soup. For context, I eat homemade meals almost exclusively. I freeze them in tupperware, because I make huge pots of soup, I mean, just absolutely massive. Obviously, when a liquid is frozen, it expands. Thus, it forms a vacuum in the container. Run under hot water, it loosens a little, but it gets stuck in there sometimes.
Now, the slightly annoying part. Sometimes, the container overflows. It's hard to fill a bunch equally, without waste, and account for the "new and improved" containers that get made every two weeks so they're all different sizes and volume. Again, water expands when frozen, so the fill line is unreliable. It gets the lid stuck, but, more importantly, leaves no gap between the lip of the container and the frozen broth. I usually press on the bottom of the containers to get rid of that vacuum, but the missing gap means I'm just pressing on a block of ice.
Imagine my surprise when I realised my square containers just perfectly sat on top of the pot when turned upside down, like a lid. Now, overfilling doesn't matter. I can just press, and it drops out, without fail. I sometimes don't even need hot water. It filled my autism-riddled brain with joy to discover this!
I have thus unlocked infinite soup storage by simply storing it in a one-dimensional point. Campbell's will pay me millions, assuming that we can figure out how to store a point with infinite mass.
You get the ultimate free spout unlike the abject compromise that is the corner of square tupperware and you get far more options for tessellation when storing items in the fridge or freezer.
Considering freezer storage tessellation as a deciding factor in your storage container shapes feels like putting theory way ahead of practice. But I still want them.
I think there's actual logic here. If you're storing a liquid, you're probably going to be getting it out with a big spoon, so the round sides make that easier than flat sides and corners. If you're storing something like lasagna, you're probably cutting servings into squares/rectangles, so the flat sides make more sense.
As someone who cooks large batches of food to freeze, the problem with round is that it wastes tons of space in the freezer. I just use scores of rectangular cubes and my freezer is completely full.
That's always the trade-off. Square ones fit better. Round ones are easier to wash (the corners non-round ones are slightly annoying to deal with depending on what was on the tupper)
If you're storing a lot of liquid you'll probably want to pour it out later. In that case square is better as the corners will provide a bit of spout action.
This ladle is reinforced silicone in the back half of the scoop, and soft, flexible silicone on the front half, so you can scoop into corners easily. It's very nice, even for cylindrical containers because there is still a corner where the wall meets the bottom.
