French onion soup is a classic French dish that is beloved around the world for its rich, deeply flavorful broth and melt-in-your-mouth toasted bread and cheese topping. This soup is made by slowly caramelizing onions in butter or oil until they are amber brown and incredibly sweet and jammy. The onions are then cooked in a broth seasoned with herbs and sherry or wine. The soup is topped with toasted or grilled bread and melted cheese and broiled until the cheese is bubbly and browned.
Does French onion soup expire?
Like most soups and stews, French onion soup can go bad after a period of time. How long it lasts depends on several factors:
- Ingredients used – Fresh, high-quality ingredients will last longer.
- Storage method – Proper refrigeration or freezing extends shelf life.
- Prepared vs. homemade – Homemade will not keep as long as store-bought.
- Reheating – Repeated reheating shortens shelf life.
With optimal storage, homemade French onion soup will last 3-5 days in the refrigerator. Commercially prepared, preservative-containing soups can last 7-10 days refrigerated. Frozen French onion soup, whether homemade or store-bought, can last 2-3 months in the freezer.
How to tell if French onion soup has gone bad
Here are some signs that indicate your French onion soup has spoiled and should be discarded:
- Appearance – Soup looks curdled, separated, watery or has an uneven texture.
- Mold – Fuzzy mold colonies appear anywhere on the soup.
- Off odors – Smells sour, rancid or unpleasant.
- Off flavors – Strong bitter, sour, unpleasant tastes.
- Expired – Soup has exceeded recommenced shelf life.
The first sign of spoilage in French onion soup is usually an off smell or taste. Visible mold or drastic changes in texture or appearance also indicates it should be tossed.
How to store French onion soup properly
To maximize the shelf life of homemade or store-bought French onion soup:
- Refrigerate in airtight container. Leave room for soup to expand as it freezes.
- Allow to cool completely before refrigerating.
- Use within 3-5 days for homemade, 7-10 days for commercial soup.
- Freeze for longer term storage up to 2-3 months.
- Reheat gently on stove or in microwave until heated through.
- Avoid reheating more than once.
- Do not leave soup sitting out at room temperature.
What ingredients make French onion soup go bad faster?
Some ingredients in French onion soup can accelerate spoilage. These include:
- Dairy – Milk, cream, cheeses are highly perishable.
- Meat – Beef or chicken stock can spoil quickly.
- Onions – Will spoil faster than other vegetables.
- Bread – Can mold quickly.
- Wine/Sherry – Alcohol and acids break down over time.
Using fresh, high-quality dairy, meats and produce and minimizing contact between the toast/cheese topping and soup can help French onion soup stay fresh longer.
Can you eat French onion soup that’s been left out overnight?
It is not recommended to eat French onion soup that has been left out at room temperature overnight. Bacteria can multiply quickly in the moist, protein-rich environment of the soup. Reheating may not be sufficient to destroy harmful bacteria that has grown. If more than 2 hours have passed since the soup was left out, it is safest to discard.
Can spoiled French onion soup make you sick?
Consuming spoiled, contaminated French onion soup can cause foodborne illness. Potential dangers include:
- Salmonella – From undercooked meats, symptoms may include vomiting, fever, diarrhea.
- E. coli – From contaminated ingredients, causes abdominal cramps and bloody diarrhea.
- Bacillus cereus – From starchy foods, can cause vomiting and diarrhea.
- Listeria – From unpasteurized dairy, flu-like symptoms, headache, stiff neck.
- Staphylococcus aureus – From contaminated food, nausea, vomiting, diarrhea.
Groups at higher risk for severe illness include pregnant women, young children, older adults and those with compromised immune systems. When in doubt, throw it out!
Tips to minimize French onion soup spoilage
Some tips for making your French onion soup last as long as possible include:
- Use freshly made beef or chicken stock.
- Cook onions slowly over low heat.
- Bring soup to a boil before refrigerating.
- Cool quickly before refrigerating; don’t leave at room temp.
- Freeze broth and onions separately for longer shelf life.
- Refrigerate soup and toast/cheese topping separately.
- Use soup within 3 days, don’t reheat more than once.
Conclusion
Like any food, French onion soup has a limited shelf life. With proper refrigeration and freezing, homemade soup will last 3-5 days and commercial soup 7-10 days. Reheating more than once is not recommended. Signs of spoilage include odor, texture, and appearance changes. Consuming spoiled soup can cause food poisoning. Following food safety guidelines carefully can help maximize the shelf life of your French onion soup.