Posted: 11/10/2010 8:01:24 AM EDT
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I use the cold water defrost method for meat pretty frequently.
Where a frozen carcass or cut is placed in a large bowl which is filled with cold water and then a slow trickle of cold water is cascaded into the bowl. It works like a champ but, the geek/miser/hippy in me got me to thinking about all the water I was wasting. So, I was wondering, would adding a submersible pump to the rig accomplish the same circulatory effect as the slow trickle or, is the introduction of the slightly less cold water (along with the expulsion of the slightly colder water) really that big of a factor in the thawing process. If it is, could I use a fountain pump (perhaps with a shower head type attachment placed, say, 12-18 inches above the water surface to act as kind of a "phase change" system. Possibly to reintroduce the water already in the bowl back in after having traversed the pump>line>ambient atmoshpere to remove the chill it picked up from the water bath? So, hive, what say you? I could buy or scronge all of the parts I'd need for either solution for under 20 bucks. I figure I'd save that cost in water after a while (albeit a long while) but, I'd also be conserving water in the long run. |
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its all about heat transfer. 3 modes of heat transfer (not including mass transfer) are conduction, convection and radiation. moving water provides convection. if you wanted, you could also put some heat sink to trnasfer heat from the water to your house temperature, but thatd be a bit extreme and would take up more space. Posted Via AR15.Com Mobile |
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Just place the frozen "carcass" in the microwave for 15-30 minutes on UBER high. Rest assured that it WILL be thawed. The method I described in my first post is superior to all methods of defrosting (from a finished product stand point) except thawing in the fridge. I don't like to cook the food I'm defrosting before I actually start to cook the food. |
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its all about heat transfer. 3 modes of heat transfer (not including mass transfer) are conduction, convection and radiation. moving water provides convection. if you wanted, you could also put some heat sink to trnasfer heat from the water to your house temperature, but thatd be a bit extreme and would take up more space. Posted Via AR15.Com Mobile That was one reason I suggested the phase change shower head rig. It would only be a small tube with a garden shower head on it but, it might cause the water to lose some of its chill as it cascades through the ambient air. Still cheap and compact and not overly complex but, possibly a better solution than just churning the water. |
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To answer your question, absolutely.
They make thermal circulators for cooking too. I saw a device on TV once that looked kind of like a immersion blender that clipped onto your sink/container, and turned the water to provide circulation for thawing. I cant find one online though. I do not think the slow introduction/ removal of water really matters. It is just a matter of equalizing temps between your foodstuff and the water it is surrounded by, and circulating that water does the trick. Just like a convection oven. |
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If you use a bigger bowl with more water, the water will stay warming longer and help defrosting. Sure, but the point of this exersice is to determine whether the pump moving around the "same" water will be as effective as introducing new water to provide the circulation. If it is, then I could, conceivably, use less water for the same result, which was my ultimate goal. |
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To answer your question, absolutely. They make thermal circulators for cooking too. I saw a device on TV once that looked kind of like a immersion blender that clipped onto your sink/container, and turned the water to provide circulation for thawing. I cant find one online though. I do not think the slow introduction/ removal of water really matters. It is just a matter of equalizing temps between your foodstuff and the water it is surrounded by, and circulating that water does the trick. Just like a convection oven. Yeah, I'm familiar with sous vide. If this rig works and I can find a reliable way to heat and maintain the temp of the water I may end up with a two for one, circulating thawing machine and sous vide cooker. I can get the cheap fountain pumps online for under 10 bucks shipped so, I was hoping to adapt one of those to this project. |
| I use the water method as well however I do it a little different. I fill the container with warm water and submerge the package of meat. That's it. Fifteen to 20 minutes later it is thawed. There is no extra water to waste. Moving water would be a little more efficient but even if it was 20% more efficient that would only make a 3 minute difference the overall defrost time. |
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If your goal is to minimize water use, you could circulate the water through a heat exchanger. To minimize energy usage, you could use an aluminium pot and make sure the cold meat is elevated so that it is at the top of the water. The water near the meat will get colder and sink to the bottom. It will self circulate, but it won't be as efficient as forced convection with a heat exchanger.
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Quoted: Quoted: If you use a bigger bowl with more water, the water will stay warming longer and help defrosting. Sure, but the point of this exersice is to determine whether the pump moving around the "same" water will be as effective as introducing new water to provide the circulation. If it is, then I could, conceivably, use less water for the same result, which was my ultimate goal. Doubtful that it will help much to recirculate the water... "fresh" tap water comes it at what? 55*? 60*? whatever...it isnt really anywhere near freezing. Recirculated water would drop to 32* (or close enough) and stay there (other than the minimal amount of warming caused by pump friction and any pipes acting as radiators). What makes the slightly running tap water thing work is that you are replacing the volume of 32* water with warmer water. Now if you would heat up your recirculated water back to whatever temp tap water is it would work. (and in case you were wondering the reason you use cold water is to keep the water against the food below "danger temp" -approx 40*- using warm/hot water would encourage bacteria growth) |
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I use the water method as well however I do it a little different. I fill the container with warm water and submerge the package of meat. That's it. Fifteen to 20 minutes later it is thawed. There is no extra water to waste. Moving water would be a little more efficient but even if it was 20% more efficient that would only make a 3 minute difference the overall defrost time. All of my study on the matter has shown that cold water will actually defrost meat more quickly than warm water. I'm not a thermodymic science guy but I think it has something to do with the ambient and internal temperatures being closer and thus having less "distance" to travel in the difference during the convection process. By the way, I don't think your thaw time is accurate for things like a 3-4 pound roast. Mine usually take an hour of thaw time in my method. Mass of the meat has a lot to do with the speed at which it will defrost, obviously. |
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If you use a bigger bowl with more water, the water will stay warming longer and help defrosting. Sure, but the point of this exersice is to determine whether the pump moving around the "same" water will be as effective as introducing new water to provide the circulation. If it is, then I could, conceivably, use less water for the same result, which was my ultimate goal. Doubtful that it will help much to recirculate the water... "fresh" tap water comes it at what? 55*? 60*? whatever...it isnt really anywhere near freezing. Recirculated water would drop to 32* (or close enough) and stay there (other than the minimal amount of warming caused by pump friction and any pipes acting as radiators). What makes the slightly running tap water thing work is that you are replacing the volume of 32* water with warmer water. Now if you would heat up your recirculated water back to whatever temp tap water is it would work. (and in case you were wondering the reason you use cold water is to keep the water against the food below "danger temp" -approx 40*- using warm/hot water would encourage bacteria growth) Won't the large surface area of the top of the bowl or pot heat the the water to ambient as it exposed? Maybe a heat exchanger is a better way to go. |
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The reason you use cold water as opposed to warm water to thaw frozen items is that the cold water will keep your food out of the danger zone.
You don't want your food to get above 40 degrees F. Warm water will actually thaw your meat faster, but it will allow for bacteria growth. Whatever you do, make sure to keep your temperatures in mind. |
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My only concern with that is keeping the pump clean. Getting little food particles and juices in their could make one very sick after repeated uses. I always defrost my meat in sealed ziptop packages. Further, since this will be a "culinary tool" all the regular sanitation principles would apply to its cleaning and maintenance. |