If the power goes out while you’re gone, everything from meat to milk will be at risk.
As Sheila Pulanco Russell, from North Carolina, explains in her post, all you need is a quarter and cup of water. Put the water in the freezer until it’s frozen solid. Then, take it out, and put a quarter on top of the ice. Return the cup—with the quarter—back to the freezer.
When you return, if you find the quarter has moved to the bottom of the cup, then you’ll know your food was unrefrigerated while you were gone and it’s no longer safe to eat. Found the quarter in the middle? The food is likely still okay, but, as Sheila advises, “If you don’t feel good about your food, just throw it out.”
Where you ideally want the quarter to be is exactly where you left it—on the top. That means your freezer’s contents stayed frozen the entire time. Genius, right?