Cooking Splatter


by bjarnidk
Tags: cooking, splatter
Jolb
Jolb is offline
#19
Aug23-13, 12:48 PM
P: 419
Quote Quote by sophiecentaur View Post
I don't think it can be "surface tension" in the liquid. However, when a liquid in a jar boils very rapidly you can get 'bumping' when the pressure in the bubble is higher than the hydrostatic pressure. Most boiling situations are more than that, I think. When you fry an egg, you aren't dealing with a liquid - it only splatters when the white starts to form and you have the possibility of small 'balloons' of the solid cooked protein forming, which can withstand higher pressures before bursting or before the edge of the egg lifts of the bottom of the pan. You can get a similar effect (rattling) if you put flattish ceramic pieces on the bottom of a pan (anti-bumping chips). The water boils explosively underneath by being constrained temporarily by the chip but the 'explosions' are very small and safer than a violent boiling.
I wonder if the GF is just winding the OP up by dropping debris in the water and seeing what sort of nerd reaction she will get? I have been suckered into things like that 'cos I can't help wearing my Physics hat.

You should cook Pasta in an open pan but Stir it Regularly, osib. I was served DISGUSTING spaghetti in Rome (of all places) with clumps of uncooked pasta. I chickened out of complaining.
All that is interesting but I don't see any argument for why my suggestion is wrong. Surely you agree that spattering of boiling pasta sauce is due to bubbles of fluid rather than "protein balloons"/popcorn kernels. When cooking an egg, don't you think it's possible that some water from the egg gets trapped in an oil bubble which pops? That would definitely open the possibility of spattering, right? And the theory would apply to any fluid [with surface tension], whereas the popcorn theories rely on specific chemistry happening. As an example that has no fancy chemistry going on, and one you can try in your kitchen, just pour a little water into a hot pan of oil. You'll get spatter [provided the oil's reasonably hot]. Nothing coagulates into a solid in that example.
sophiecentaur
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#20
Aug23-13, 12:57 PM
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Quote Quote by Jolb View Post
All that is interesting but I don't see any argument for why my suggestion is wrong. Surely you agree that spattering of boiling pasta sauce is due to bubbles of fluid rather than "protein balloons"/popcorn kernels. When cooking an egg, don't you think it's possible that some water from the egg gets trapped in an oil bubble which pops? That would definitely open the possibility of spattering. And the theory would apply to any fluid [with surface tension], whereas the popcorn theories rely on specific chemistry happening. As an example that has no fancy chemistry going on, and one you can try in your kitchen, just pour a little water into a really hot pan of oil. You'll get spatter. Nothing coagulates into a solid.
I wouldn't disagree with that. Bubbles form whether or not you have a pure liquid or a composite material like pasta sauce. I say "composite" because things don't all classify as solid liquid or gas. When a bubble reaches the surface of water, it collapses harmlessly. When it cets to the top of the sauce, the situation is more complicated and it doesn't surprise me that it could form droplets around the edge of the main bubble. These droplets could easily be thrown out of the pan. The surface tension could be very low. There's the possibility of standing waves as the bubble releases and collapses. Nothing would surprise me as it won't behave like a straightforward liquid so I don't think you can predict on the basis of how water behaves.
When you have hot oil and water, the oil can exist as a liquid above 100C so the water is likely to boil explosively under those conditions, under hot oil.
Jolb
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#21
Aug23-13, 01:22 PM
P: 419
Here's another [surprisingly trippy] video of what happens to a water droplet in hot oil. All of this seems to be submerged in the oil/water but you can see violent things happening to the surface of the vapor bubble. http://www.youtube.com/watch?v=gltxUjB8jNA


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