Defrosting frozen meat takes an excruciatingly long time. I try to be good about remembering to take meat out of the freezer and move it to the refrigerator in enough time to be able to eat it when I want it, but it's so easy to forget, and it's so tempting to just toss the meat in the microwave. But food scientist Costas Stathopoulos, a professor at Abertay University in Dundee, says defrosting frozen meat in the microwave is not ideal.
The Right Way to Thaw Meat
The absolute best way to thaw frozen meat is to move it to the refrigerator and leave it there until it is completely thawed. That's the safest way to thaw meat, because the meat never winds up in what the USDA calls the "danger zone," of between 40 and 140 degrees Fahrenheit, which is where bacteria starts to multiply rapidly.
The refrigerator method means the meat can thaw, but it never gets warm enough for the bacteria to start breeding quickly, so it's safer to eat. According to the USDA, if you thaw meat in the refrigerator, you can even freeze it again safely if you change your mind without cooking it, and then eat it later.
The refrigerator thawing method also gives the meat a better texture when it's cooked, because freezing causes meat to lose moisture. When meat is defrosted in the fridge, some of that moisture is slowly reabsorbed by the muscle fibers. With quick-thaw methods, the meat is more likely to just lose that moisture and taste a little drier and tougher after it's cooked.
The problem with refrigerator thawing is that it is really, really slow. Even something small like a frozen chicken breast can take all day to thaw in the refrigerator.
Why You Shouldn't Defrost Meat in the Microwave
According to the Daily Mail, Stathopoulos went on an episode of the BBC Two's Inside the Factory to talk about food safety, and he says microwaves are not ideal for defrosting frozen meat because some areas of the food can become warm and start to cook, so you run the risk of overcooking part of the meat. The USDA says that thawing in the microwave is safe, but because it can quickly bring meat into the "danger zone" where bacteria multiply most rapidly, meat defrosted that way should be cooked immediately as soon as it's thawed.
Professor Stathopoulos and the USDA both say meat should never be defrosted in hot water or by leaving it out on the counter at room temperature, because both methods bring the outer surface of the food into the too-warm "danger zone" while the middle is still frozen.
The fridge might be the safest, but it really does take a long time. When you really can't wait that long, another safe and useful method to defrost meat more quickly is to use tepid water, not hot. It's much faster than the refrigerator, but it's still safe and does not run the risk of prematurely cooking the meat.