The Surprising Safety Reason You Should Always Keep a Quarter in Your Freezer (It’s So Smart!)

It’s officially the chilliest time of year, and if you live in an area with frequent power outages due to weather or other unpredictable events, you know the struggle of losing valuable food in your refrigerator and freezer when the power goes out. That’s exactly what inspired North Carolina resident Sheila Pulanco Russell to come up with this interesting — and although completely nonscientific, pretty ingenious — way to determine roughly how long a power outage lasted, and whether food in the freezer or fridge might still be safe to eat. Enter: the “quarter freezer trick.”

Originally shared in a since-deleted viral Facebook post, Russell shared her hack for timing power outages a few years ago. To try this trick, take a cup or mug of water and put it in the freezer, allowing it to freeze completely solid. This should be done well in advance of a power outage, so if there’s a storm in the forecast, go ahead and freeze the water right away so it’s ready when you need it. (Make sure to use a sturdy mug; otherwise the expanding ice can break the container.)

Once the water has frozen solid, place a quarter on top of the ice and return the cup to the freezer. You’ll want this to be in place before the power goes out. In fact, if you see frequent power outages in your area, it’s a good idea to just keep this in your freezer at all times. 

The main premise of the quarter freezer hack is that if the power goes out and the freezer starts to warm up, the ice will start to melt and the quarter will sink. As it does, the position of the quarter gives you a rough idea of whether the temperature of your freezer stayed within a safe range for food safety requirements. 

The location of the quarter can give you an idea of how long the power was out. If the quarter is halfway down the cup when you check it, you can assume that the temperature was low enough for a long enough period to prevent substantial bacterial growth when the power came back on and it refroze. On the other hand, if the quarter has fallen all the way to the bottom, it can be assumed that the power was out long enough for the ice to melt all the way, even in a closed freezer, which could be as much as 48 hours. So, how accurate is the hack, really?

According to Amie Alexander, a registered dietitian with Nutri Peak, the quarter freezer trick does work, but only to an extent. “This is a nonscientific approximation, as it does not actually tell much of anything about the length of time the power was out or how much the freezer temperature fluctuated,” she says. “Because the melting rate is dependent on the ambient conditions, there is no accurate estimation on how long the power outage will last just by looking at the position of the quarter.”

A better way to determine whether the food in your freezer is still safe after any power outage, Alexander says, is to use a freezer thermometer that will indicate the highest temperature reached.

According to the U.S. Food and Drug Administration, food in a refrigerator will stay cold for four hours in a power outage. A fully stocked freezer can stay cold for up to 48 hours, but if your freezer is sparse, this is cut in half to only 24 hours. It’s crucial to keep the freezer and refrigerator doors tightly shut at all times during a power outage in order to maximize the amount of time your food stays safe to eat.

Food safety guidelines:

• Fully stocked freezer: 48 hours
• Sparsely stocked freezer: 24 hours
• Refrigerator: up to 4 hours

Food safety is crucial during winter storms, and luckily, there are some easy things you can do to extend the life of your food during a power outage. Here are some guidelines set forth by the FDA to preserve your food and protect yourself from foodborne illness after a power outage: 

• Use appliance thermometers. Your freezer should be set at 0°F, and your refrigerator should be set at 40°F.
• Freeze plenty of water for ice in advance. Having extra ice on hand allows you to keep your freezer colder longer, or fill coolers to store food for short periods of time. 
• Move refrigerated items to the freezer. The goal isn’t to freeze these items, so this should be done on a short-term basis. Doing this can keep perishable refrigerated items at safer temps longer, and can keep your freezer full, which keeps it colder, longer. 
• Consider purchasing dry ice. This can be used to keep your freezer colder for longer periods of time. 

It can be difficult to determine if the food in your freezer and refrigerator is safe after a power outage. Of course, tricks like the quarter freezer hack shouldn’t be relied on completely, as it’s best to be extra cautious when it comes to food safety. Alexander advises inspecting the food carefully. “Check for thawing and temperature changes when checking if frozen food has spoiled. If food contains ice crystals or is cold to the touch, below 40°F, it is typically safe to refreeze or cook,” she says.  

Perishable foods in the refrigerator are often the foods that will go bad first, so it’s crucial to inspect them and deal with them right away. When it comes to refrigerated foods, rely on your senses, Alexander says. “Spoiled meat, for example, often develops a sour smell, a slimy texture, or color change. Milk or yogurt may be curdled in texture or have an off smell. Generally, hard cheeses are a bit more forgiving, but soft cheeses and eggs should be discarded if left unrefrigerated for more than two hours.”

Even though it can be difficult with the high price of groceries these days, it’s always best to err on the side of caution when it comes to food in your freezer or refrigerator after a power outage. “When in doubt, it’s best to throw out food to be on the safe side,” Alexander says.

Have you tried this “quarter freezer trick”? Let us know in the comments below!