Does hot water freeze faster than cold water? It seems obvious that the answer should be no, because all things being equal, hot water takes longer to cool down than cold water, and so it couldn't possible freeze faster.
Why does cold water defrost things faster than hot water
But observations over thousands of years, as well as countless modern experiments, have shown that the opposite is true - under carefully controlled conditions, hot water at times seems to freeze faster than cold water.
As the video above explains, the phenomenon of hot water freezing faster than cold water is known as the Mpemba effect, named after Erasto Mpemba, a Tanzanian student who in 1963 was making ice cream as part of a school project.
Intrigued by this phenomenon, he went on to work with physics professor Denis Osborne, and together they were able to replicate the findings and publish a paper in 1969 showing that warm water freezes faster than cold water.
It was the first peer-reviewed study on the effect, but as Derek notes in the video above, observations date all the way to Aristotle in the 4th century BCE, who observed that hot water cooled sooner than cold during his experiments.
2) Cold water bath. Fill the sink or a pot big enough to hold the meat with cold water. Put the meat in a watertight plastic zipper bag. Leave the bag unzipped at first, and slowly submerge it keeping the zipper above water. The water pressure will push out all the air. Then zip it up tight. Leave it in cold water, and hold it under with a plate if necessary. Stir it occasionally to break up the envelope of cold water surrounding the meat. Make sure the water is under 40F. Add cool water or ice cubes if needed. If you have a digital thermometer, use it to monitor the water temp. Allow 30 minutes per pound, so if you have a 20 pound turkey, you will need 10 hours, so make sure to set the alarm for early Thursday morning!
Smaller cuts of meat, such as a pound or less, will thaw out in an hour or less. Larger pieces of meat such as pieces between three and four pounds may take two to three hours to fully thaw out.if(typeof ez_ad_units!='undefined')ez_ad_units.push([[300,250],'profamilychef_com-medrectangle-4','ezslot_3',138,'0','0']);__ez_fad_position('div-gpt-ad-profamilychef_com-medrectangle-4-0');The question is: do you thaw meat in cold, warm, or hot water?It is safe to thaw meat in cold water. But it is not safe to thaw meat in hot water. Meat should be thawed in water at a temperature of 40F or less. This is safe and much faster as the water is a great conductor of heat, being able to transfer heat faster than air.Can you thaw frozen meat in warm waterAccording to the United States department of Agriculture, food that falls under the category of perishable food should never be left on the counter at room temperature for more than two hours, and should also not be left on the counter to thaw out. In addition, it should not be thawed out in warm water either.When using warm water to thaw meat products, you will be able to effectively thaw the meat, but you will also possibly begin to cook the meat. Certain parts of the meat surface may start to cook and the temperature may rise above 40F (4C). This is a problem as it will put the meat in what is known as the danger zone.The danger zone is a temperature range between 40F and 140F (4C and 60C ) where microorganisms will start to form on the surface of the perishable food item. It may cause food-borne illnesses to develop which may make you very sick.if(typeof ez_ad_units!='undefined')ez_ad_units.push([[250,250],'profamilychef_com-leader-3','ezslot_12',186,'0','0']);__ez_fad_position('div-gpt-ad-profamilychef_com-leader-3-0');Can you defrost frozen meat in hot waterif(typeof ez_ad_units!='undefined')ez_ad_units.push([[300,250],'profamilychef_com-banner-1','ezslot_4',175,'0','0']);__ez_fad_position('div-gpt-ad-profamilychef_com-banner-1-0');This debate is quite similar to defrosting meat in warm water. While you can do it, there is a series of potential health risks involved and that is why most food experts and chefs would highly recommend that you do not do it.Much like warm water, hot water may defrost the meat but may also cause parts of the meat to start cooking and place these parts or the whole piece of meat in the danger zone.if(typeof ez_ad_units!='undefined')ez_ad_units.push([[300,250],'profamilychef_com-leader-1','ezslot_6',177,'0','0']);__ez_fad_position('div-gpt-ad-profamilychef_com-leader-1-0');While it is not recommended by the United States Department of Agriculture, New York Times states that there have been studies conducted which indicate that it may in fact be safe to thaw meat out in hot water.However, the methods are not yet recommended. What the study highlights is that it is possible to do this without causing the meat to enter the danger zone.if(typeof ez_ad_units!='undefined')ez_ad_units.push([[300,250],'profamilychef_com-box-4','ezslot_7',174,'0','0']);__ez_fad_position('div-gpt-ad-profamilychef_com-box-4-0');Can you thaw frozen ground beef in hot waterif(typeof ez_ad_units!='undefined')ez_ad_units.push([[300,250],'profamilychef_com-large-mobile-banner-1','ezslot_9',180,'0','0']);__ez_fad_position('div-gpt-ad-profamilychef_com-large-mobile-banner-1-0');Ground beef should never be thawed in hot water. Raw meat naturally has a layer of bacteria that sits on the surface of the meat. With ground beef, this surface layer of bacteria is spread out throughout the meat.Thawing ground beef in hot water will cause the surface of the meat to start cooking and will subsequently place the meat in the danger zone.In order to thaw ground beef, the meat must be placed in a sealable plastic bag. The bag must be placed in a bowl of cold tap water and allowed to thaw out. The water should ideally be changed every 30 minutes or so to ensure that the meat is thawing in temperature approriate water.if(typeof ez_ad_units!='undefined')ez_ad_units.push([[300,250],'profamilychef_com-large-mobile-banner-2','ezslot_10',185,'0','0']);__ez_fad_position('div-gpt-ad-profamilychef_com-large-mobile-banner-2-0');Can you thaw hamburger meat in hot waterHamburger meat and ground beef are essentially the same thing. There is a key difference between the two though. While both products may contain beef fat, hamburger meat may not contain more than 30% of the beef fat.if(typeof ez_ad_units!='undefined')ez_ad_units.push([[250,250],'profamilychef_com-leader-2','ezslot_11',182,'0','0']);__ez_fad_position('div-gpt-ad-profamilychef_com-leader-2-0');The same rule that applies to thawing ground beef in hot water also applies to thawing hamburger meat in hot water. The water may cause the meat to start cooking and place it directly in the danger zone.if(typeof ez_ad_units!='undefined')ez_ad_units.push([[250,250],'profamilychef_com-leader-4','ezslot_15',192,'0','0']);__ez_fad_position('div-gpt-ad-profamilychef_com-leader-4-0');Can you run hot water over frozen meatNo. Running hot or even warm water over frozen meat is essentially much worse than putting the meat on the counter and allowing it to thaw over several hours.The hot water will cause the surface of the meat to start cooking. In addition, by placing the meat under a stream of hot water will only cause one section of the packaged meat to start cooking while the rest of the meat remains frozen. This is very dangerous.It may be better to run cold tap water over the frozen meat. As previously stated, water is an excellent conductor of heat. The water may allow the meat to defrost quicker, provided that is is below 40F.Alternatively, you could place the meat in a sealed ziplock back and place the meat in a salt water bath. The melting temperature of saltwater is lower than normal tap water which may help to defrost the meat even faster.Does meat thaw faster in cold water or hot waterHot water may thaw the surface area of the meat much faster but leave the center of the meat cold. This creates a situation where the meat enters the danger zone.Cold water on the other hand, may help to thaw out food much faster and is essentially much safer than thawing food in hot water.This is because water heat capacity allows it to thaw out meat faster. The heat capacity of water refers to its ability to store heat inside. Essentially, the cold water holds a lot of heat energy inside which the meat is able to absorb.This allows the meat to thaw out much faster in cold water than in hot water.
And evaporation may not be the only reason the water can freeze more quickly. There may be less dissolved gas in the warmer water, which can reduce its ability to conduct heat, allowing it to cool faster. However, Polish physicists in the 1980s were unable to conclusively demonstrate this relationship.
A non-uniform temperature distribution in the water may also explain the Mpemba effect. Hot water rises to the top of a container before it escapes, displacing the cold water beneath it and creating a "hot top." This movement of hot water up and cold water down is called a convection current. These currents are a popular form of heat transfer in liquids and gases, occurring in the ocean and also in radiators that warm a chilly room. With the cooler water at the bottom, this uneven temperature distribution creates convection currents that accelerate the cooling process. Even with more ground to cover to freeze, the temperature of the hotter water can drop at a faster rate than the cooler water.
Since the time of Aristotle, researchers and amateur scientists alike have batted about the counterintuitive theory that hot water freezes faster than cold. The notion even has a name: the Mpemba effect, named for a Tanzanian schoolboy who in 1963 noticed that the ice cream he and his classmates made from warm milk froze quicker than that made from cool milk.
The phenomenon that hot water may freeze faster than cold is often called the Mpembaeffect. Because, no doubt, most readers are extremely skeptical at this point, weshould begin by stating precisely what we mean by the Mpemba effect. We start withtwo containers of water, which are identical in shape, and which hold identical amounts ofwater. The only difference between the two is that the water in one is at a higher(uniform) temperature than the water in the other. Now we cool both containers,using the exact same cooling process for each container. Under some conditions theinitially warmer water will freeze first. If this occurs, we have seen the Mpembaeffect. Of course, the initially warmer water will not freeze before the initiallycooler water for all initial conditions. If the hot water starts at 99.9C, andthe cold water at 0.01C, then clearly under those circumstances, the initially coolerwater will freeze first. But under some conditions the initially warmer waterwill freeze first: if that happens, you have seen the Mpemba effect. But you willnot see the Mpemba effect for just any initial temperatures, container shapes, or coolingconditions. 2ff7e9595c
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