How to Freeze Leftovers & Reheat Them Safely – Foods That Last

You have three leftover pancakes from breakfast, two slices of bacon, and some lasagna from dinner a few nights ago. These odds and ends are taking up room in your refrigerator, and if you don’t eat them soon, you’ll have to toss them.

One option is to freeze them. Freezing leftovers is an economical way to make the most of your food budget and ensure nothing goes to waste.

But the benefits of freezing leftovers don’t end with your pocketbook.

Benefits of Freezing Leftovers

It’s been a busy day, and your family is getting home much later than you’d planned. You’re all hungry, and you don’t have anything prepared for dinner. Fortunately, last week’s leftover frozen chicken chili is in the freezer, so you quickly pull it out and put it on the stove to reheat while you help the kids get started on their homework.

This scenario highlights one of the many benefits of freezing leftovers. Having an arsenal of already cooked food in your freezer can be a lifesaver on busy days when you haven’t had time to prepare anything else. And instead of scrambling to pull dinner together at the last minute, you can spend that time with your family or prepare some fresh vegetables to go with the meal.

Knowing how to freeze food properly can also help you cook more efficiently. You can batch cook on the weekends and freeze those dinners to reheat and eat during the busy workweek. You can also cook a double batch of one meal during the week and freeze the extra for another meal.

Last, freezing leftovers helps you avoid food waste and make the most of your grocery budget. Instead of letting it go bad in the refrigerator, you can promptly freeze leftovers and preserve them for another meal. But freezing food only benefits you if you know how to do it right.

How to Freeze Leftovers

There’s a lot more to freezing food than just putting them in a zip-close bag and tossing them in the freezer. If you want your food to last and taste delicious when it’s time to reheat it, there are some guidelines to follow.

Don’t Wait

Don’t let your leftovers languish for days in the refrigerator before you decide to freeze them. Freeze your food at their peak of freshness so it tastes better when reheated. Whenever possible, freeze them the same day you cook them to ensure their color, texture, and flavor are what you expect when it’s thawed.

Don’t Put Hot Food in the Freezer

It’s best to let your leftovers come to room temperature before putting them in the freezer. There are several reasons for this.

First, putting hot food in the freezer forces it to work harder to cool the food down, which uses more energy. Placing hot food in the freezer can also cause surrounding food to partially thaw, which could lead to freezer burn and food waste.

However, according to the Food Network, leftovers should not sit out at room temperature for more than two hours. If the environmental temperature is above 90 degrees F, such as at a summer cookout, they should only sit out a maximum of one hour.

Keep Your Freezer Cold

According to the United States Department of Agriculture (USDA), setting your freezer to 0 degrees F to render bacteria, yeasts, and molds inactive. However, note that freezing doesn’t destroy these microbes. As soon as the food thaws, the bacteria can become viable and lead to foodborne illness.

That’s why it’s crucial you handle frozen food just as you would fresh food, using the same safety precautions like washing your hands and cooking it thoroughly before consumption.

Freeze in Small Portions

Have you ever had to thaw a gallon-size zip-close bag of soup? It’s neither quick nor easy to do.

You can save time by freezing food in smaller, meal-size portions. That also helps you avoid food waste since you shouldn’t freeze thawed frozen food a second time.

Smaller portions also allow food to freeze faster, which preserves quality.

Get the Air Out

Air is your enemy when it comes to freezing foods because it can contribute to freezer burn and cause the food to deteriorate faster.

Food develops freezer burn when exposed to air in cold temperatures.

Freezer burn occurs when the moisture in food freezes. This moisture then migrates to the surface of the food. Although freezer-burned foods are safe to eat, they’re often tasteless or have an unpleasant texture. People usually throw freezer-burned food away because they don’t want to eat it.

When freezing foods in zip-close bags, get as much air out as possible by squeezing it as you seal the top.

Use a Vacuum Sealer

A more efficient way to remove air and avoid freezer burn is to purchase a vacuum sealer, such as the FoodSaver. Vacuum sealers seal food in an airtight plastic bag, which prevents freezer burn and enables frozen food to stay palatable for up to three years.

Vacuum sealers also help you save money because you can purchase food in bulk and freeze it safely and efficiently for long-term storage. You can also stock up on foods like meat when it goes on sale. Repackaging it in amounts you’re likely to eat with a vacuum sealer ensures the food stays fresh and your investment doesn’t go to waste.

Buy a Stand-Alone Freezer

Many people store their frozen foods in the freezer attached to the refrigerator. These small freezers are useful for short-term food storage, but they’re not ideal for storing frozen foods long-term. There are several reasons for this.

People open small refrigerator-freezers frequently, which lets in moisture and warmer air. These temperature and humidity fluctuations degrade the quality of everything in there. The University of Minnesota Extension states that these temperature fluctuations also cause water migration to the surface of the container. This moisture loss leads to freezer burn.

Refrigerator-freezers are also very small, which means you can’t store much food in them. All it takes is a few days of leftovers before it’s too full for anything else.

Buying a stand-alone freezer gives you a lot more flexibility when it comes to freezing foods. It provides you with plenty of room for leftovers, and it also allows you to freeze foods at a colder temperature than your refrigerator-freezer. For example, refrigerator-freezers typically freeze foods at 0 degrees, while stand-alone freezers can freeze foods at minus 10 or lower.

Stand-alone freezers can also freeze foods faster than a refrigerator-freezer, which preserves quality. The USDA explains that slow freezing allows large ice crystals to form on food. During thawing, these ice crystals destroy cellular walls, which causes foods to drip and lose moisture, according to North Dakota State University.

Rapid freezing prevents these large ice crystals from forming, so it retains moisture and tastes better.

Pro tip: If you’re planning to purchase a stand-alone freezer, home improvement stores like Home Depot and Lowe’s frequently run sales around major holidays like Memorial Day, July Fourth, and Labor Day. Making your purchases at these times can help you save money.

Always Label

Before you put leftovers in the freezer, make sure you label the package with the date and type of food. Don’t assume you’ll remember what it is — the chances are good you’ll forget. And if you don’t know what it is or how long it’s been in the freezer, you’re probably not going to eat it.

You can easily label frozen food containers with a marker and a strip of masking tape or purchase removable food labels.

Label Food In Refrigerator Containers

Best Leftovers to Freeze

Opening up the freezer and seeing a stack of food that’s already cooked can be a relief, especially when you’re short on time or energy (or both). But some foods freeze and reheat better than others.

Chili & Soup

Chili and soup both freeze and reheat very well.

If your chili or soup has a lot of fat content, let it cool completely and then skim most of the fat off the surface before putting it into the freezer. Fat causes spoilage over time, even in the freezer, and shortens the life of the food.

The best way to store chili and soup is in freezer bags. But remember, liquids expand when frozen, so leave an inch of space at the top for expansion. Lay the bags flat to freeze, and then stand them upright once frozen to maximize your freezer space, make the labels easier to read, and help it thaw faster.

If you have time, the best way to defrost soup is to put it in the refrigerator and slowly thaw it. Typically, that takes 24 to 48 hours, depending on volume.

If you don’t have that much time, follow these tips:

  • Place the bagged soup in a warm water bath until it’s fully thawed. Then heat the soup or chili on the stove.
  • If you’re in a hurry, place the soup or chili in a warm water bath just until the sides have thawed enough for the food to slide out of the container easily. Then, reheat on the stove over medium-low heat.
  • You can also thaw soup in the microwave using the defrost setting (just make sure the brand of zip-close bag you used is microwaveable). If you’re concerned about leakage, you can set the bag in a microwave-safe casserole dish. Check your microwave’s user manual for specific instructions on using the defrost setting. For example, on some microwaves, you select “defrost” and then estimate the number of ounces rather than setting the number of minutes. Check the soup halfway through the defrost cycle to make sure it’s not overcooking. Once the soup is completely thawed, you can transfer it to a microwave-safe bowl and heat it using the cook setting.

Many soups thicken during the freezing process. If the soup is too thick once it’s reheated, add 1/2 cup water or broth. You can also add more flavor with a spritz of lemon juice or a dash of salt.

Baked Pasta Dishes

Baked pasta dishes like lasagna and baked ziti usually freeze very well, which is why you see so many of these prepared meals in the frozen foods section of the grocery store.

When freezing these leftovers, put them in foil pans and make sure all the meat is covered with sauce and not left in the open air. Because the sauce is a liquid, you need to leave some headspace for expansion. Cover the pan with the lid and some aluminum foil, sealing it tightly around the edges by crimping the lid and pan together. (If the lid is cardboard, lay plastic wrap down first to prevent it from sticking.)

When you’re ready to eat, you can put the frozen pasta dish right into the oven.

  1. Preheat the oven to 375 degrees F.
  2. Take off the lid (if plastic or cardboard), replacing the foil if necessary, and place the entire container directly into the oven.
  3. Bake until the pasta is hot in the center, which could take an hour or longer, depending on how large the dish is.

If that baked pasta appears too thick while it’s cooking, add some tomato sauce or olive oil and stir to combine.


Meatloaf is an iconic, family-friendly dinner many people love to eat. And it also freezes well.

There are two ways to approach meatloaf when it comes to freezing: you can freeze it uncooked or cooked.

Raw Meatloaf

Many home cooks swear meatloaf tastes better and is moister when it’s frozen raw. You can do that by making a double-batch, freezing one loaf and cooking the other for dinner.

To thaw the raw frozen meatloaf, take it out of the freezer and let it thaw in the refrigerator overnight. To bake, simply follow the instructions in the original recipe.

If you don’t have time to let it thaw overnight, put the meatloaf in a bread pan or casserole dish and bake it at the original temperature, but for 1 1/2 to 2 times longer than the recipe calls for.

Use a meat thermometer and bake it until the internal temperature reaches 160 degrees F.

Cooked Meatloaf

You can also freeze leftover cooked meatloaf. However, keep in mind that frozen cooked meatloaf can develop a mushy texture once thawed if you don’t package it well. Cooked meatloaf with sauce often freezes better than plain meatloaf.

If you choose to freeze cooked meatloaf, first let it cool completely. Slice the leftover loaf into individual portions. Wrap each meatloaf slice tightly in plastic wrap or aluminum foil to preserve moisture and then store it in a freezer bag. Take care to get as much air out of the bag as possible. If you have a vacuum sealer, you can also vacuum-seal the meatloaf after it’s frozen to extend its shelf life.

To reheat cooked meatloaf, let it thaw in the refrigerator overnight and reheat in the microwave for at least two minutes, or until the center is 160 degrees.

You can also reheat frozen cooked meatloaf in the oven.

  1. Preheat the oven to 350 degrees F.
  2. Remove the wrapping and place it in an oven-proof container. Cover it with foil.
  3. Bake it for one and a half hours, or until the internal temperature has reached 160 degrees F.

Mashed Potatoes

Making a large batch of mashed potatoes and then freezing half lets you make sides for two meals simultaneously.

Most potatoes freeze well, but low-starch potatoes freeze best. Low-starch potatoes have waxy skins, like red or purple fingerlings. High-starch potatoes, like russet or King Edward potatoes, can become grainy once they’re frozen and reheated.

To freeze mashed potatoes, first let them cool completely.

If you want to freeze individual portions, use an ice cream scoop to portion out the cooled potatoes and put them on a cookie sheet in rows. Put the entire tray in the freezer. Once the potatoes are completely frozen, take them off the tray and put each portion into a freezer bag.

If you want to freeze a family-size portion, put all the mashed potatoes into a large gallon-size freezer bag. Get all the air out and then smooth the bag flat. Freeze the bag flat on its side. Once the potatoes are frozen, you can stand up the bag to save space.

If you’re short on time, you can thaw frozen mashed potatoes in the oven or microwave.

One method is to reheat them on the stove. Slide the frozen mashed potatoes out of the bag or container into a pot and cook over low heat, stirring occasionally. Add butter, milk, or cream if the consistency is too thick.

You can also thaw mashed potatoes in the microwave. Remove the mashed potatoes from the bag or container and put them in a microwave-safe dish. Cover and cook at 50% power for four to six minutes, stirring halfway through.

If you have more time, you can put frozen mashed potatoes in the refrigerator and thaw them overnight.

Pot Roast

After cooking, slice the roast so it can cool quickly and remove as much fat as possible. Separate the roast into individual portions. Place the slices in freezer-safe plastic containers and cover them with sauce or gravy to help them retain moisture. Make sure you leave headspace for liquid expansion.

You can reheat the pot roast in the oven.

  1. Preheat the oven to 350 degrees F.
  2. Run the plastic container under warm water until the pot roast inside is thawed enough to slide out.
  3. Place the frozen pot roast in an oven-safe dish. Cover it with foil, and bake it 1 hour, or until it’s a minimum of 145 degrees F in the center.

Breakfast Casseroles

Breakfast casseroles are perfect for lazy weekends, but they can also make a delicious and filling dinner. These meals are useful when you have a lot of odds and ends in the refrigerator that you don’t want to waste. You can gather everything up, throw it into the casserole dish with the eggs, and bake it until it’s done. And the cooked leftovers freeze well.

To freeze leftover breakfast casseroles, divide it into individual portions, and wrap each one in plastic wrap. Then wrap each in aluminum foil.

To reheat it, thaw it in the refrigerator for 24 hours and reheat in the microwave. Or you can cook a whole frozen casserole in the oven.

  1. Preheat the oven to 350 degrees F.
  2. Place the unwrapped casserole in an oven-safe dish.
  3. Bake for 20 to 30 minutes, or until the center is hot.

Breads, Waffles, & Pancakes

Homemade bread only lasts two to three days before it starts to get stale or grow mold. You can extend the life of your homemade or store-bought bread by freezing it.

Bread, pancakes, and waffles all freeze very well, and if you do it right, they emerge just as moist and fresh as the day you made them.


If the bread just came out of the oven, let it cool completely. Then, wrap it tightly in plastic wrap, and then wrap it with aluminum foil. When you’re ready to thaw the bread, take it out of the freezer and let it sit out overnight on the countertop.

You can also slice your bread before you wrap and freeze it. Preslicing enables you to take out a few slices at a time without having to thaw the entire loaf at once.

Waffles & Pancakes

Freezing leftover waffles and pancakes is similar to freezing bread. Let them cool completely, and then wrap each one individually in parchment paper. Then, wrap the entire batch up in aluminum foil or put them in a large freezer bag, taking care to get as much air out as possible. You can thaw frozen waffles and pancakes in the microwave or put them directly into the toaster.

Rice & Other Grains

Like mashed potatoes, freezing leftover rice or other grains can help speed up dinnertime during a busy week. You can freeze white rice, wild rice, brown rice, farro, quinoa, wheat berries, barley, or buckwheat.

To freeze leftover grains, let them cool completely and put them in a thin layer in a freezer bag. Freezing the grains in a thin layer helps them evenly thaw when you’re ready to eat. Once they’re frozen, you can stack the bags upright to save space.

To thaw, put the grains in a microwave-safe bowl, sprinkle with a tablespoon of water, and cover. Microwave for one minute, stir, and then add another minute, continuing until the grains are hot and ready to eat.


Yes, you can freeze fish, thaw it, and eat it again. However, frozen leftover fish doesn’t taste like it did when it was freshly cooked.

Epicurious experimented with cooking and freezing salmon to find out if there is a taste difference between different methods. They cooked one fillet, promptly froze it, and then put it straight into the oven the next day, cooking in a 325 degree F oven for 40 minutes. They cooked another fillet, froze that one, and then thawed it for six hours before reheating it in the oven at 325 degrees F for 10 minutes. Then they cooked a final fillet right before serving.

As you can imagine, the freshly cooked salmon tasted best. The salmon fillet they thawed before reheating was tacky but still edible. The fillet they put directly into the oven while still frozen tasted like it came from a can.

The team at Epicurious suggests that if you’re going to freeze leftover fish, you find a different way to use it besides serving it alongside steamed veggies and rice pilaf. Some ways to use up frozen fish include putting it into a soup or curry dish or creating a paste to spread on crackers. You can also pull the fish apart and make fish burgers.

To freeze leftover fish, put it in a freezer bag and squeeze out as much air as possible. Better yet, vacuum-seal it for maximum freshness.

When you’re ready to eat it:

  1. Thaw it in the refrigerator for at least six hours.
  2. Preheat the oven to 325 degrees F.
  3. Take the fish out of the refrigerator and let it sit on the counter 20 minutes while the oven preheats.
  4. Put the fish in an oven-safe dish and cover with foil.
  5. Cook the fish in the oven for eight to 12 minutes, depending on the size of the fillet.

Before eating, drizzle it with olive oil or butter to add moisture or follow Epicurious’ advice to find an alternative use.

Frozen Salmon Vacuum Sealed Package Fillets

Foods That Don’t Freeze Well

Freezing works great for many foods, but some ingredients simply don’t work well in the freezer. Some of these include:

  • Cabbage
  • Celery
  • All salad greens
  • Sprouts
  • Cream-based soups or gravies
  • Sour cream
  • Mayonnaise or salad dressing
  • Fried foods (except for fried potatoes and fried onions)
  • Baked goods with frosting already applied
  • High-moisture fruits like watermelon, apples, or oranges

If your leftovers contain a significant portion of some of these ingredients, you’re better off not freezing them and trying to eat them quickly.

Final Word

Always make sure you have plenty of freezer-ready containers on hand. That makes it easy to freeze food and prevent a last-minute run to the grocery store. Containers that work best for freezing include freezer-safe zip-close bags, BPA-free plastic containers, glass Mason jars, and foil pans.

What’s your favorite leftover freezing method?