Extra food should be eaten, not tossed.

Few things are worse when you're hangry than pulling out a tupperware of Monday’s leftovers for today’s lunch, only to find it’s somehow already spoiled. Lots of things can cause this disappointing occurence, and all of them can be avoided. Here, a round-up of 12 common storage mistakes that are ruining your food along with expert advice for living that #leftoverslife right.

Relying on aluminum or plastic.

Aluminum foil and aluminum bowls may seem like easy storage options, but they shouldn’t be your go-tos, especially when it comes to dairy and acidic foods like marinades and tomatoes, says Harley Peet, executive chef at Bluepoint Hospitality Group in Easton, Maryland.

That’s because the aluminum reacts with these types of foods and creates a “weird astringent taste that’s like chewing on aluminum foil,” he says. What’s more, though aluminum bowls in general can be useful for baking or marinating, they’re bad in the fridge on multiple counts. “You can’t see what is in there and they tip over and roll easily,” says Peet, which can ruin the contents inside—as well as surrounding leftovers.  

Foil is also a no-go for baked goods. “It doesn’t keep moisture very well,” says Tiffany MacIsaac, founder and owner Buttercream Bakeshop in Washington, D.C.

Though it depends on what type of leftovers you’re storing, glass containers, in general, are your best bet, says Peet. When compared to their more popular plastic counterparts, they don’t absorb the flavors of your food (more on that in a minute), the lids don’t get warped in the dishwasher (which means they’ll always fit tightly), and they’re more environmentally friendly. They’re also easy to organize. “At home, I use a bunch of mason jars and vintage glass milkware,” says Peet. “It stacks really nicely in the fridge.”

Simply covering your plate of food with a layer of plastic wrap.

“If you are making dinner and your spouse is coming home in an hour, sure that’s ok,” says Peet. “But it’s not any type of proper long-term storage,” as it leaves food susceptible to smashing, spills, and odor leakage. Instead, put things in proper storage containers.

Popping leftovers in the fridge uncovered.

“Fridges are just big cold dehydrators,” says Peet. “If food is left uncovered in a fridge, it will get very dry.” The exception to this rule is any braised item, like short ribs, that has a layer of fat coagulated on top. “This creates an airtight feel,” explains Peet, “and is completely acceptable to leave uncovered in the fridge.” Just know that once you start serving the dish and remove that protective layer, you should not put it back in the fridge uncovered. Transfer it to a glass container.

Setting your fridge temperature too high or too low.

The ideal fridge temp is between 38 and 40 degrees, says Peet. Anything above or below this compromises the quality of your food—and in the case of warmer temperatures, it also compromises the safety of your food. “Between 40 and 140 degrees is the danger zone for food,” says Peet. Items kept within this temperature range are at increased risk of bacteria growth. Check your fridge thermometer on the reg to make sure the Mercury reads a safe and ideal level.

Overstuffing your fridge—or placing all of your items one on shelf.

Your fridge will not work correctly if it’s too full or if everything is placed on one side or one shelf. “The air won’t circulate properly in either case,” explains Peet, “and this will throw off the internal temperature” (see dangers of that above). Keep this in mind as you store and organize items.

Sticking hot food directly into the fridge.

Placing a hot item, like a container of soup, into your fridge throws off the temperature calibration system and can “freeze up the unit really quick,” says Peet. Instead, let your goods cool to room temperature before popping them in.

Storing raw and cooked foods together.

Raw products, like uncooked meats and fish, should be stowed on the bottom shelf of your fridge, and cooked leftovers should be packed above, says Peet. “You don’t want raw food juice dripping on ready-to-eat foods,” says Peet. “Storing food in the proper area of the fridge is crucial.”

Letting pungent items run loose.

Be mindful of where you stash super pungent items, like sauteed onions or garlic. Ideally, these are kept in airtight containers and placed far away from foods that easily absorb other scents, like cooked rice, says Peet, or high-fat items, adds MacIsaac, like frosting or a bowl of homemade whipped cream.

Waiting too long to wrap your food.

With baked goods in particular, the key is wrapping them when they’re “ever so slightly warm to the touch,” says MacIsaac. This traps steam that will keep the item moist and delicious. “Don’t let it sit out,” she says. Plastic wrap is your best bet for quality storage, says MacIsaac, though freezer bags work well too.

How long it takes an item to get to this wrappable point depends on the type of item. If it’s something sturdy, like a muffin, it can get covered fairly soon after it emerges from the oven. If it’s something more delicate—like a cookie—wait a little while longer to ensure it doesn’t crumble when packaged.

The exception to this is homemade bread, which should be kept uncovered at room temperature for 1 to 2 days to keep a “nice crust,” says MacIsaac. After that point, or once you cut into the bread, put it into a ziploc bag for storage. That said, softer breads, like brioches, should be stored in ziploc bags from the get-go (once they’re properly cooled, that is, per the tips above).

Using smelly containers.

If you don’t have glass containers and instead rely on plastic tupperware, be aware that over time, the material can permanently absorb the flavors of especially pungent leftovers and thus spoil the taste of future foods. Give your containers a sniff before popping in fresh eats.

Letting your fridge get messy.

If you pile everything into the fridge with no rhyme or reason, you’ll likely forget certain items are there...until you discover their fur-covered remains months later. Keep your fridge organized, with certain shelves designated for certain types of items, and schedule regular cleanings to ensure no leftover is forgotten.

Refrigerating the wrong things.

Not all leftovers need to be refrigerated. In fact, certain foods—including the majority of baked goods, like cakes and pies—are best preserved at room temperature, says MacIsaac.

“Cakes can seem dry if they’re left in the fridge,” she explains. Leave cakes out on the counter—either uncovered or beneath a cake dome for up to 2 days. Pies with fruity fillings should be left completely uncovered, as wrapping them could “lock in too much moisture,” says MacIsaac. If you cut into your cake or pie, cover the exposed area with plastic wrap or wax paper to prevent the rest from drying out, and leave rest uncovered.

If you’re enjoying cake or pie beyond a few days, it’s probably best to stick it in the fridge for optimal preservation. Just make sure it’s well covered—with plastic wrap, wax paper or an airtight dome—so that it doesn’t absorb other odors in the fridge. And if your baked good contains cheese and/or fresh fruit—like a marscapone cake or cheesecake—it’s best stashed in the fridge within the first day of baking.

If, for any reason, you stashed a baked good in the fridge and find it’s rather dry come eating time, wrap it in a slightly damp paper towel and pop it into the microwave for a quick zap. “This will help steam it so doesn’t taste as dry,” says MacIsaac. The trick “can bring things back from the dead.”