Leftovers — whether planned or unplanned, it’s important to know when to throw them out.
Saved for too long, bacteria and mold can grow to unsafe levels, making your leftovers unsafe to eat.
This article explains everything you need to know about leftovers, including when to throw them out, how to label and store them properly, and how to make them last longer.
How long do leftovers last?
Refrigerating food — including leftovers — is an effective way to slow the growth of bacteria and molds.
Bacteria and molds that make you sick and cause foodborne illnesses are called pathogens.
Refrigeration, however, only slows the growth of these pathogens — it doesn’t stop it.
Therefore, there is a limit to how long you can keep leftovers before you must throw them out to keep your customers, family, or you from potentially becoming ill.
This rule applies to time and temperature control for safety (TCS) foods.
As the name suggests, TCS foods require certain time and temperature controls to prevent bacteria from growing and multiplying.
TCS foods include items like milk and milk products, meats, poultry, seafood, cooked rice, and baked potatoes.
The 7-day rule also applies after opening most packages containing TCS foods like hot dogs, milk, or cottage cheese.
For optimal freshness and quality, however, you should serve or toss most leftovers within 3–4 days.
Remember to keep the temperature of all refrigerators out of the temperature danger zone at 41ºF (5ºC) or below.
Here’s a look at various foods and when you should throw them out for optimal quality and freshness:
|Refrigerator (41ºF or below)
|Freezer (0ºF or below)
|Egg, chicken, ham, tuna, and macaroni salads
|Fresh hamburger, ground beef, turkey, chicken, and mixtures of them
|Fresh steaks, chops, and roasts
|Fresh chicken or turkey
|Meat or poultry
|Cooked beef, pork, and chicken
|Casseroles with eggs
|Do not freeze
|Soups and stews
|Vegetables or meat added
|Cooked salmon, tuna, cod, tilapia, etc.
|Smoked or processed
|Shucked clams, mussels, and oysters
You can store leftovers safely for up to seven days if you hold them at 41ºF (5ºC) or below, with the day of preparation or opening counting as the first day. For optimal freshness and quality, however, you should consume or toss most leftovers within 3–4 days.
Labeling and storage
Labeling allows you to store food using the first-in, first-out (FIFO) method.
The day of preparation or opening counts as the first day, so if you prepared a dish or opened a food item on October 13th, you would need to consume or toss any leftovers by October 19th at the latest based on the 7-day rule.
Some packaged items may have a use-by or best-by-date that is less than seven days from the date it was opened.
However, use-by and best-by-dates are measures of quality, not safety (except for baby formula).
These dates indicate the last date on which the product will be of the best flavor and quality.
So as long as food shows no signs of spoilage, such as an off smell, color, or texture, it should be safe.
Knowing when to throw leftovers out is an important component of food safety, but so too is how you store leftovers in the refrigerator.
You should store leftovers and other ready-to-eat foods on the top shelf in the refrigerator to prevent other foods from dripping or spilling on them.
Store other items in order of their minimum internal cooking temperature, with those that require the highest on the bottom.
Here is the proper storage order for refrigerated foods, in order from top to bottom:
- ready-eat-foods and leftovers
- whole cuts of beef and pork
- ground meats and seafood
- whole and ground poultry
Label leftovers with the item name, the date prepared, and the date it must be eaten, sold, or tossed. Store leftovers and ready-to-eat foods on the top shelf in the refrigerator to avoid contamination from other items.
How to make your leftovers last longer
Unlike refrigeration, freezing stops the growth of harmful pathogens.
So if you don’t plan on consuming or serving leftovers within seven days, it’s best to freeze them.
Just remember that if you store leftovers in the refrigerator before moving them to the freezer, you still need to count those days in the refrigerator as part of the 7-day rule.
Similar to the game red light, green light, bacteria are given the green light to grow in the refrigerator but the red light when frozen.
Once the food is back in the refrigerator to thaw, the bacteria are given the green light to pick back up where they left off and continue growing.
For example, if you cook chicken on October 1, refrigerate it for two days, freeze it for four days, and thaw it on October 8th, the food will need to be consumed or tossed no later than midnight of October 11th.
|Shelf Life Day
|Consume or toss
Maintain a freezer temperature cold enough to keep food frozen, usually around 0ºF (-18ºC).
Although you can safely store foods in the freezer indefinitely, there is a limit to how long you can store them before they lose quality and freshness.
Freezing stops the growth and bacteria but it doesn’t reset the 7-day timer after you remove food from the refrigerator to thaw.
The bottom line
Although refrigeration slows the growth of most bacteria, they can still grow to unsafe levels and cause a foodborne illness if the food is stored for too long.
You should toss leftovers and other cold-kept foods that you open after a maximum of seven days.
To retain optimal freshness and quality, however, you should use leftovers within 3–4 days.
Label leftovers that you hold for more than 24 hours with the item name, the date it was prepared, and the date on which it should be eaten, sold, or tossed.
Freezing stalls the growth of bacteria but it doesn’t reset the 7-day rule once you transfer it to the refrigerator for thawing.
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