Tartar sauce is a popular condiment often served alongside seafood dishes like fish and chips or shrimp. It has a creamy, tangy flavor from ingredients like mayonnaise, dill pickles, capers, onions, and lemon juice. But what happens if you accidentally leave tartar sauce out on the counter overnight? Is it still safe to eat?
The Short Answer
No, tartar sauce that has been left out at room temperature overnight should not be consumed. Tartar sauce is a perishable food due to its egg and dairy ingredients. Left at room temperature for too long, it can enable the growth of harmful bacteria that could cause foodborne illness.
Examining the Ingredients in Tartar Sauce
To understand why tartar sauce is not safe after sitting out overnight, it helps to look at its main ingredients:
- Mayonnaise – Mayonnaise is an emulsion of egg yolks, oil, and an acid like lemon juice or vinegar. The egg yolks make mayo potentially hazardous. Bacteria can grow rapidly in foods with eggs if left unrefrigerated.
- Dairy – Tartar sauce also contains dairy products like milk, sour cream, or yogurt. Dairy products are highly perishable and can also grow bacteria quickly at room temperature.
- Vegetables – Tartar sauce typically contains vegetables like pickles, capers, onions, and parsley. Vegetables raise the moisture content and provide nutrients for bacteria.
- Acid – Tartar sauce is acidic thanks to ingredients like lemon juice and vinegar. But the acidity alone is not enough to prevent bacterial growth after prolonged time above 40°F.
Why Refrigeration is Critical
Refrigerating tartar sauce is vital for food safety because cold temperatures slow the growth of harmful bacteria. The “danger zone” for bacterial growth is between 40°F and 140°F. By keeping tartar sauce refrigerated at 40°F or below, you slow bacterial growth significantly.
However, leaving tartar sauce or any mayo-based sauce out at room temperature overnight allows the product to remain in the “danger zone” for many hours. Even if the sauce was safely stored before, bacteria can multiply to unsafe levels in just 2 hours when left between 40-140°F.
Risks of Eating Tartar Sauce Left Out Overnight
If you eat tartar sauce that has sat at room temperature overnight, you put yourself at risk for potential foodborne illness. The main risks are:
- Salmonella – Raw egg yolks used in mayonnaise can harbor Salmonella. It can multiply quickly in tartar sauce left out.
- E. coli – Ingredients like dairy products and vegetables may be contaminated with E. coli, which can grow rapidly if left unrefrigerated.
- Staph aureus – Staph bacteria is commonly found on hands, kitchen surfaces, and utensils. It can get into foods and produce toxins.
- Listeria – Listeria bacteria can live at refrigerator temps and spread from ingredients like dairy products.
- Bacillus cereus – Spores of this bacteria can survive cooking and grow into cells in room-temp foods.
Symptoms of foodborne illness include nausea, vomiting, stomach cramps, and diarrhea. In some cases, severe illness can result if dangerous strains like E. coli O157:H7 or Salmonella typhimurium contaminate the tartar sauce.
How to Know if Tartar Sauce is Bad
If you’re unsure whether your tartar sauce is still safe after sitting out on the counter all night, look for the following signs of spoilage:
- Changes color – It should not be dark yellow, green, or gray.
- Separate oil – You see a layer of oil sitting on top of the sauce.
- Curdled appearance – The texture becomes curdled or lumpy.
- Mold – You see fuzzy mold growing on the surface.
- Smells bad – It has a unpleasant, rotten, or ammonia-like smell.
You should discard the tartar sauce if you observe any of those changes. Do not taste or smell the sauce, as that could transfer bacteria into your mouth and make you sick.
How to Store Tartar Sauce Properly
To keep tartar sauce safe and avoid the risk of food poisoning, follow these storage guidelines:
- Refrigerate after opening – Keep tartar sauce chilled at 40°F or below.
- Use within 3-4 days – Consume within 3-4 days for best quality.
- Store in airtight containers – Keep in an airtight container to prevent contamination.
- Don’t double dip – Use a clean utensil each time to avoid introducing bacteria.
- Follow recipe instructions – When preparing homemade tartar sauce, follow a trusted recipe and food safety practices.
Discard any leftover tartar sauce after 3-4 days. Don’t rely on your sense of sight or smell alone to determine if it’s gone bad.
Making Tartar Sauce Safely
When making your own tartar sauce at home, be sure to take steps to prevent foodborne illness:
- Use pasteurized eggs – Raw eggs can contain Salmonella. Use pasteurized eggs for safety.
- Keep ingredients chilled – Refrigerate mayo, dairy, and vegetables until ready to use.
- Clean surfaces and utensils – Prevent cross-contamination with good sanitation practices.
- Don’t use recalled foods – Check for any recalled onions, pickles, or other ingredients.
- Refrigerate after making – Store the finished tartar sauce in the fridge right away.
Commercial Product Safety
Commercially prepared tartar sauce sold in jars, packets, or cups from the grocery store can be treated similarly to homemade sauce once opened. However, it’s generally considered safe if left sealed at room temperature before opening. The packaging helps prevent contamination and bacterial growth. Still, it’s advisable to refrigerate after opening and follow the “use by” date on the label.
Bottom Line
So in summary, is tartar sauce safe after sitting out on the counter overnight? No. Leaving tartar sauce or any mayo-based sauce at room temperature for extended periods allows bacteria to grow to unsafe levels. Refrigeration is necessary to control bacterial growth. Tartar sauce left out more than 2 hours should be discarded. With proper storage and handling, tartar sauce can be kept fresh and safe to enjoy without risk of foodborne illness.