He's not wrong. A single layer of balls allows me to do a 72 hour cook without refilling (anova one.) You may have to double layer if you're at high elevation. Eliminating all evaporation isn't worth the amount of foil needed.
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# ? Jun 10, 2015 15:53 |
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# ? May 30, 2024 13:35 |
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taqueso posted:We just need ping pong cubes, someone could make a fortune. Quick, go find a maker space to 3d print them.
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# ? Jun 10, 2015 16:04 |
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Mr. Wookums posted:He's not wrong. A single layer of balls allows me to do a 72 hour cook without refilling (anova one.) You may have to double layer if you're at high elevation. Eliminating all evaporation isn't worth the amount of foil needed. Lol the two sheets it requires?
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# ? Jun 10, 2015 16:09 |
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Wait and see if you're still laughing when the Tinfoil Wars start!
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# ? Jun 10, 2015 16:16 |
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Jarmak posted:This sounds dumb as hell, vapor pressure inside a crimped tinfoil cover will do way more to slow evaporation then ping pong balls floating on the top. Foil (or a lid) will not affect evaporation at all per se---you're just relying on the lid to allow the water vapour to condense and drip back down into the container. Putting ping pong balls (or anything else) in the water will be less effective as a condenser than foil, but unlike foil it will actually change the rate of evaporation in the first place: the rate of evaporation is directly proportional to the surface area of the water. Ideal space packing of uniform circles on a flat plane is around 91% (ideal hexagonal packing) and absolute worst case (each circle inscribed on a square in a uniform grid) is around 75%, so the balls are going to reduce the amount of evaporative loss by about that much.
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# ? Jun 10, 2015 16:48 |
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Math!
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# ? Jun 10, 2015 16:53 |
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My replacement cooker from Sansaire arrived. Of course that leaves me with 3 ICs, so I am giving one to a guy in my office who likes to cook but hasn't gotten into SV yet. But props to the Sansaire folks for standing behind an out of warranty product.
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# ? Jun 10, 2015 16:54 |
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I'm sure someone could manage to use ping pong balls to burn their kitchen down despite being in water https://www.youtube.com/watch?v=sj0GTJnR_HI
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# ? Jun 10, 2015 17:03 |
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Jose posted:I'm sure someone could manage to use ping pong balls to burn their kitchen down despite being in water
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# ? Jun 10, 2015 17:10 |
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That was MUCH more entertaining than I expected.
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# ? Jun 10, 2015 17:15 |
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The Midniter posted:That was MUCH more entertaining than I expected.
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# ? Jun 10, 2015 17:18 |
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SubG posted:That's not what vapour pressure means. Vapour pressure is a function of temperature. If what you're trying to say is that you think a foil cover will allow the pressure over the surface of the water to rise and [something], no. You can't make a pressure cooker by tenting foil over a cambro. Sure it will, because it's increasing the humidity of the volume of air over the water. Evaporation rate is the difference between the rate at which water molecules leave the surface and fly off into the air and the rate at which water molecules in the air randomly fly into the surface of the water. If the concentration of water vapor is higher, then that latter rate is higher, so evaporation happens more slowly. If the volume of air were saturated, no evaporation would occur (well, technically it would, but it would be exactly countered by condensation and the water level would not change). Just being a physics pedant, in any actual cook the difference will, again, be approximately gently caress/all. I've done 72 hour cooks with foil and also not needed to add any water, although generally I do those in a cooler with a hole cut in the lid so I don't waste as much energy heating up my kitchen.
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# ? Jun 10, 2015 17:35 |
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Phanatic posted:Sure it will, because it's increasing the humidity of the volume of air over the water.
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# ? Jun 10, 2015 17:49 |
Household metal foils will not really reflect wavelengths of thermal energy at temperatures that water will reach in your kitchen, so use plastic wrap or some other inexpensive thing that doesn't absorb water. If anything. Styrofoam or whatever if your concerned about insulation. Just make it cheap.
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# ? Jun 10, 2015 18:04 |
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SubG posted:That's not what vapour pressure means. Vapour pressure is a function of temperature. If what you're trying to say is that you think a foil cover will allow the pressure over the surface of the water to rise and [something], no. You can't make a pressure cooker by tenting foil over a cambro. No, vapor pressure is a function of atmospheric pressure versus the hydrogen bonds of the liquid water. Temperature of evaporation is a function of vapor pressure.
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# ? Jun 10, 2015 18:13 |
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Number 1 Sexy Dad posted:Household metal foils will not really reflect wavelengths of thermal energy at temperatures that water will reach in your kitchen[...] Jarmak posted:No, vapor pressure is a function of atmospheric pressure versus the hydrogen bonds of the liquid water. Temperature of evaporation is a function of vapor pressure. Perhaps the thing you're trying to get at is partial pressure?
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# ? Jun 10, 2015 18:28 |
SubG posted:Actually aluminium foil has really good reflectance that part of the IR spectrum. I guess I will have to apologize to my girlfriend for making fun of her having bought aluminum reflectors to go behind our wall radiators.
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# ? Jun 10, 2015 18:33 |
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Safety Dance posted:I bet I could find a high temperature foam board, cut it to fit various ICs in various Cambros, and sell it at immense markup to puddledorks, billing it as the best heat and water loss solution for your most longest, most temperature sensitive sous vide applications. Hmm... I need to find suitable foam... I actually have wire I bought for robodick/ecig building that... might also be appropriate for a DIY foam cutter
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# ? Jun 10, 2015 22:40 |
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SubG posted:Actually aluminium foil has really good reflectance that part of the IR spectrum. But the function of foil tented over a water bath isn't thermal insulation so it's not particularly relevant. I wasn't using "temperature of evaporation" as a term of art, I couldn't remember the exact term I was looking for. You're right, it is partially a function of temperature, I was forgetting exactly how its measured, but its also a function of the inter-molecular forces which govern a given substance, which in the case of water is hydrogen bonds. What I should have said was that the atmospheric pressure from being covered will be far above the vapor pressure.
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# ? Jun 11, 2015 01:40 |
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Safety Dance posted:I bet I could find a high temperature foam board, cut it to fit various ICs in various Cambros, and sell it at immense markup to puddledorks, billing it as the best heat and water loss solution for your most longest, most temperature sensitive sous vide applications. Buy a big roll of Reflectix.
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# ? Jun 11, 2015 02:07 |
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Jarmak posted:I wasn't using "temperature of evaporation" as a term of art, I couldn't remember the exact term I was looking for. You're right, it is partially a function of temperature, I was forgetting exactly how its measured, but its also a function of the inter-molecular forces which govern a given substance, which in the case of water is hydrogen bonds. Jarmak posted:What I should have said was that the atmospheric pressure from being covered will be far above the vapor pressure.
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# ? Jun 11, 2015 02:55 |
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SubG posted:The industrial process that used to be used to produce celluloid resulted in a slightly acidic residue in the final product. This caused the celluloid to slowly degrade over time. One of the ways this manifested itself was increased shock sensitivity, which would sometimes result in ping pong balls spontaneously igniting when struck. Man just imagine how much more fun table tennis would be if at any time the ball might spontaneously ignite when the other guy hits it at you.
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# ? Jun 11, 2015 03:25 |
Jarmak posted:Lol the two sheets it requires?
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# ? Jun 11, 2015 04:46 |
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Mr. Wookums posted:Yes the two sheets it requires every time you do a cook adds the gently caress up. So reuse the sheets. It's not like they go bad.
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# ? Jun 11, 2015 04:51 |
While I agree, I haven't met anyone outside of boomers who reuse foil
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# ? Jun 11, 2015 04:59 |
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Uh, why aren't you guys just buying sheets of this and cutting it to the exact shape of your vizzler opening to float on top? http://www.amazon.com/Smoothfoam-Sh...styrofoam+sheet I think the normal cambro is 12.5" wide. e: Or is it 12" deep?
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# ? Jun 11, 2015 05:36 |
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I just fill the container with water and cook stuff. I haven't run out of water yet.
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# ? Jun 11, 2015 05:36 |
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Same
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# ? Jun 11, 2015 06:50 |
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Chemmy posted:I just fill the container with water and cook stuff. I haven't run out of water yet. You should cover the water with a thin layer of water to keep the water from evaporating
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# ? Jun 11, 2015 07:17 |
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The father's day deal and this potential recipe from Chefsteps (and Tested) finally got me to buy an Anova. http://www.tested.com/food/530164-tested-chefsteps-how-cook-amazing-ribs-without-smoke-or-fire/ As someone who just lost a backyard and moved into an apartment I'm really hopeful I can recapture some of the magic in my small space.
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# ? Jun 11, 2015 07:26 |
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Steve Yun posted:You should cover the water with a thin layer of water to keep the water from evaporating
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# ? Jun 11, 2015 07:28 |
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SubG posted:No, vapour pressure is a function of temperature because of intermolecular forces. They're not a separate variable. Holy poo poo guy, evaporation occurs when individual molecules become sufficiently energetic to escape the IM of the other molecules, thats why ln(P2/P1)=(ΔHvap/R)*(1T1−1T2). You don't need a loving pressure cooker to achieve pressures and gas concentrations which significantly slow evaporation at temperatures that are nearly half of the boiling point. Doing some really rough math in my head that should be something like 1/5 of the vapor pressure at 140 (which would mean its ~1/5 atm). Under those conditions your vapor and liquid phases are going to quickly hit equilibrium and evaporation will slow to basically the equivilant of whatever water vapor/pressure you're losing through leakage, which relative to a volume of water the size of a sous vide vessel ranges from minimal to negligible depending on how anal you are with the tin foil. Jarmak fucked around with this message at 16:24 on Jun 11, 2015 |
# ? Jun 11, 2015 16:21 |
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The Midniter posted:That was MUCH more entertaining than I expected. It was mostly an excuse to post the video
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# ? Jun 11, 2015 20:58 |
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Guys what if I put my sous vide setup in a walk-fridge. Or maybe a freezer? I think that'll stop evaporation.
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# ? Jun 11, 2015 22:39 |
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Sextro posted:Guys what if I put my sous vide setup in a walk-fridge. Or maybe a freezer? I think that'll stop evaporation. The only way is to fully submerge the setup.
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# ? Jun 11, 2015 23:13 |
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Jarmak posted:Holy poo poo guy, evaporation occurs when individual molecules become sufficiently energetic to escape the IM of the other molecules, thats why ln(P2/P1)=(ΔHvap/R)*(1T1−1T2). You don't need a loving pressure cooker to achieve pressures and gas concentrations which significantly slow evaporation at temperatures that are nearly half of the boiling point. Doing some really rough math in my head that should be something like 1/5 of the vapor pressure at 140 (which would mean its ~1/5 atm). Jarmak posted:This sounds dumb as hell, vapor pressure inside a crimped tinfoil cover will do way more to slow evaporation then ping pong balls floating on the top. I mean it's still wrong, but at least then it wouldn't be the not-even-wrong the original statement was.
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# ? Jun 11, 2015 23:18 |
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I've read some things here about people cooking things in a bag, freezing the bag again, then somehow heating it up again before sear. Considering the amount of time it may take to thaw something in the water, does this save much time?
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# ? Jun 11, 2015 23:20 |
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nuru posted:I've read some things here about people cooking things in a bag, freezing the bag again, then somehow heating it up again before sear. Considering the amount of time it may take to thaw something in the water, does this save much time?
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# ? Jun 11, 2015 23:28 |
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MasterFugu posted:It wouldn't take that much time to thaw in a waterbath(more so if you have a circulating SV setup), though the usefulness of doing this would depend on the amount of time between steps 2 and 3, i.e. not very useful if it's all being done the same day. It's not really a time-saving thing so much as a time management thing---get it done ahead of time so it's one less thing to worry about later.
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# ? Jun 11, 2015 23:36 |
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# ? May 30, 2024 13:35 |
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Looking to buy some cod loin or haddock. What temp should I go for here? I guess I'll throw some garlic powder, salt, pepper in the bag with a bit of olive oil, cook it for a while, and then sear it on each side and finish with a bit of lemon? Any other suggestions?
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# ? Jun 12, 2015 03:06 |