30 minutes
Best Answer: I have a circa 1950s refrigerator that needs to be defrosted at least every 4 months. What I do, is defrost it the day before I go grocery shopping so that it has a minimum of food inside. What food that is left is packed in coolers and set aside for the day.  It usually takes an entire day to thaw even a small amount of frozen food, such as a pound of ground meat or boneless chicken breasts. For large items, like a whole turkey or ham, it’ll take about 24 hours of defrosting time for every 5 pounds of food. All that waiting does have a payoff, though. Poultry, fish and ground meat that’s been defrosted in the fridge can be kept for an additional 1 to 2 days in the refrigerator before cooking. Beef, pork, lamb or veal (roasts, steaks or chops) will keep refrigerated for another 3 to 5 days after thawing. 1 Calculate the amount of days needed to defrost large items such as hams or turkeys, allowing 24 hours for every 5 lbs. ( 2 2.26 kg). 3  For example, to defrost a turkey that weighs 16 lbs. ( 4 7.25 kg), place the turkey in the refrigerator at least 3 days prior to cooking it. Method 1 of 3: Refrigerator Method. 1. Determine when to defrost your food in the refrigerator. Most items will usually defrost within up to 24 hours; however, large items such as frozen turkeys and chickens may take several days to defrost. If you think, this is going to defrost the turkey instantly, then you are mistaken. This method although may not take as long as the refrigerator method, yet you will have to spend 10 to 12 hours to get a perfectly defrosted bird. The average time required to defrost one pound of turkey is 30 minutes using this method. Now that you know the time required to defrost a turkey, you will ask me how long will a perfectly defrosted bird last. A perfectly defrosted bird can last for about 1 to 2 days in the refrigerator.  There are three safe ways to thaw ham: in the refrigerator, in cold water (in an airtight or leak-proof bag), and in the microwave. It's best to plan ahead for slow, safe thawing in the refrigerator. It will take about 4 to 6 hours per pound. Cold water thawing is faster than refrigerator thawing but requires more attention. Put ham in a leak-proof package or plastic bag and submerge it in cold tap water, changing the water every 30 minutes. Estimate about 30 minutes per pound of ham. The defrost cycle on a normal residential refrigerator/freezer is 20-30 minutes. If it was in defrost for hours the heaters in the freezer would heat it up until everything was thawed and the ice was melted! 8 hours and you would have to throw away all your meat!  • Using this thawing method, you should estimate about 30 minutes of defrosting time per pound of turkey. Approximate time to defrost a whole turkey in cold water: - 10 pounds — 5 hours - 15 pounds — 7 hours - 20 pounds — 10 hours - 25 pounds — 12 hours. • Place the frozen turkey in the fridge — be sure your refrigerator temperature is set at 40 °F or below. • You’ll need to a llow about 24 hours for each 4 to 5 pounds of frozen turkey you plan to thaw in the fridge. Approximate times to defrost a whole turkey in the fridge: - 10 pounds — 2 days plus 12 hours - 15 pounds — 3 days plus 18 hours - 20 pounds — 5 days - 25 pounds — 6 days plus 6 hours. Check out this handy online calculator to determine how long it will take to defrost your frozen turkey You’ll need to change the water every 30 minutes to ensure that it stays sufficiently cold. Using this thawing method, small packages of frozen meat or poultry (about a pound) can defrost in one hour or less. For larger items, you should estimate about 30 minutes of defrosting time per pound of food. Once the food is thawed completely, you’ll need to cook it immediately. Poultry, fish and ground meat that’s been defrosted in the fridge can be kept for an additional 1 to 2 days in the refrigerator before cooking. Beef, pork, lamb or veal (roasts, steaks or chops) will keep refrigerated for another 3 to 5 days after thawing. It will take about 4 to 6 hours per pound. Cold water thawing is faster than refrigerator thawing but requires more attention. Put ham in a leak-proof package or plastic bag and submerge it in cold tap water, changing the water every 30 minutes. Estimate about 30 minutes per pound of ham. 
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how long does defrosting take