How to Keep Leftovers Fresh

General Outlook

The experts advise proceeding with care.  Over time, leftovers can lose their appeal and even represent a health danger if not consumed soon.  Learn the correct way to store food, how long it keeps in the fridge or freezer, and how to tell if it has gone bad.

Is it safe to eat leftovers that pass the "sniff test"?  Does it matter if you can't tell how long something has been in the fridge before you eat it?

Is It Dangerous to Eat Old Food Leftovers?

As they sit in the fridge, leftovers transform.  Penn State Department of Food Science senior extension program specialist for food safety and quality, Martin Bucknavage, states, "They will slowly begin to spoil because of the growth of microorganisms" (University Park, Pennsylvania: Penn State Food Science, 2015). 

According to Zachary Cartwright, PhD, a leading food scientist at Aqualab (a food safety technology company) and an expert in the food safety and quality management division of the Institute of Food Technologists (IFT) (a worldwide organization that works to advance the science of food), this includes bacterial growth such as Salmonella, Listeria, E. coli, and Clostridium perfringens. 

The proliferation of bacteria in food can lead to food poisoning.  Produce, in addition to animal products like meat, dairy, and eggs, can have bacteria that cause sickness. 

He says that symptoms like nausea, vomiting, diarrhea, and stomach cramps are common in cases of food poisoning. 

Some groups are more likely to experience serious food poisoning than others. These include the elderly, children under the age of 5, those with compromised immune systems (such as those with diabetes, kidney disease, autoimmune disorders, or liver or kidney disease), and pregnant women. 

Mold can develop in any leftover food, regardless of how well you store it in the fridge.    Consumption of food contaminated with mold can trigger allergic reactions, respiratory problems, and general illness. 

Even if you do eat them, old leftovers won't look, taste, or feel good.  Bacteria that cause spoiling are to blame.  Meat becomes foul-smelling and produce becomes mushy or slimy due to this bacterium.  Although spoilage bacteria may not cause illness in humans, they do impart a bad flavor to food, according to the United States Department of Agriculture (USDA).

How Many Days Can You Keep Refrigerated Leftovers?

Food preservation

Most leftovers, according to Bucknavage, are safe to eat for three or four days.  He notes that this is conditional on a number of variables, including the specific food type, the amount of moisture in the food, the amount of time the food rested after cooking, and the cleanliness of the kitchen.

Although some foods won't be suitable for that long, a general rule of thumb is three to four days.  Alyssa Simpson, RDN, a digestive health nutritionist in Phoenix, Arizona, adds that cooked foods such as casseroles, roasted veggies, and pizza tend to hold up well for that amount of time, whereas delicate cold salads or shellfish could go bad sooner. 

She suggests eating dressed cold salads within a day or two.  For example, romaine lettuce mixed with vinaigrette would turn into a mushy mess after a few months in the fridge, ruining the salad's flavor and texture.  If at all feasible, cook only the amount of food you intend to eat in a single sitting.

Remember that the three- or four-day rule applies to restaurant leftovers when you dine out.  However, you should know that out of an abundance of caution, some specialists, like Simpson, trash them sooner.  According to her, you have no idea how much time the restaurant spent preparing them.

What is the refrigerator life expectancy of leftovers?

According to Cartwright, freezing stops the formation of microorganisms, thus you can eat frozen food forever.  However, four months is the maximum time that leftovers should be kept in the freezer, according to most recommendations. 

Food loses some of its flavor and texture as its quality declines with time.  Foods can vary in this regard.  For instance, unlike cooked chicken, leftover pizza pieces tend to dry out and acquire freezer burn quite fast.

You can see the recommended storage durations for different types of leftovers in the chart below.  For advice on how to keep food fresh in the freezer, check out the instructions. 

 Delicious food stored in the refrigerator or freezer

 

The above charts are sourced from the link below

https://www.foodsafety.gov/food-safety-charts/cold-food-storage-charts

Red Flags That Indicate Bad Leftovers

Keep an eye out for telltale indicators that your leftovers have gone bad, since there are a lot of variables that might impact their safety to consume. 

In general, our specialists advise throwing out any leftovers that have:
Some people may describe the smell as sour, putrid, stinky, or chemical-y, and it is definitely "off.

•  Fizzing or bubbling
• Modifications to the texture, including a change in hardness or sliminess
• Changing the color, such as becoming yellow or more muted in hue
• Mold growth detection
• Food that has too much liquid in it or that curdles
• Unusual or harsh flavor

 "Any food that doesn't look or smell right should be thrown away because it's probably spoiled," advises Bucknavage.  "If you're not sure, just toss it," Cartwright says.

How to Keep Leftovers Fresh: 7 Pointers

You can keep leftovers safe and delicious by storing them properly.  After preparing a dinner at home or bringing one from a restaurant, you can do the following:

• No more than two hours in the fridge.  Toss it if it's been over two hours.  Perishable foods only have one hour to remain safe in temperatures above 90 degrees Fahrenheit.

Simpson recommendation 

• Simpson recommends storing food in shallow, sealed containers so it can cool evenly and rapidly.  
• Splitting a big pot of soup or other hot food into smaller containers will allow it to cool more quickly and evenly.
• As Simpson points out, stacking containers prevents airflow around them.  As a result, cooling may be slowed. 
• Put a label on each container. 
• Mark and identify the date and contents using masking tape and a marker. 

Cartwright suggestions 

• "Make sure there's no misunderstanding regarding the storage duration of leftovers," advises Cartwright.
• Cartwright recommends keeping containers on the middle shelf of the refrigerator because that's where the temperature is most consistent.  (Raw meats and other items shouldn't be placed above other foods to prevent contamination.) 
• When storing food in the freezer, put older items in the rear and more recent items at the front.
• According to Cartwright, the best way to avoid freezer burn is to use airtight containers or freezer bags while freezing. 
• Make sure to squeeze out all the air from the container before freezing.
• Before serving, reheat completely. 
• The USDA states that for hot foods, the minimum allowable interior temperature is 165 degrees Fahrenheit. 

 What You Should Remember

• Refrigeration usually extends the shelf life of leftovers by three or four days.  Store them in the freezer for as long as you like, but eat them within three or four months for the greatest flavor and quality. 
• The type of food determines how long certain leftovers will last; therefore, those guidelines may not always be accurate.
• Indications of spoilage include odd flavors, discoloration, liquid separation or curdling, and the presence of mold.  When in doubt, toss it.
• To keep leftovers fresh for up to two hours, put them in shallow, airtight containers, and don't stack them; then, transfer them to a middle shelf.

Conclusion

When storing leftover food, especially in the freezer or refrigerator, exercise caution.  Make sure there are no strange or off-putting odors before eating food that has been preserved.  Take the necessary precautions to prevent becoming unwell if it is accidentally consumed.