Can ketchup go bad?

In this short article, we will provide an answer to the question “can ketchup go bad?” and the ways to find out its spoilage and methods to store it properly.

Can ketchup go bad?

Yes, although tomato ketchup is generally regarded as a shelf-stable product, it is not immune to spoilage. The shelf stability of ketchup can be attributed to several factors. 

Its low pH level, along with the inclusion of sodium benzoate and the application of heat during the manufacturing process, contribute to its ability to resist spoilage. 

When it comes to acidic foods like ketchup with a pH below 4.0, spoilage is typically limited to non-spore-forming bacteria (such as lactic acid bacteria), yeasts (such as Saccharomyces spp. and Candida spp.), or mold (such as Byssochlamus fulva). 

While other groups of microbes may also cause spoilage when the pH ranges from 4.0 to 3.8, their growth is significantly slowed down. (1)

How To Determine If Ketchup Is Safe To Consume?

There are several key indicators that can help determine whether ketchup has gone bad. To make a final assessment, carefully inspect the appearance, color, smell, and taste of the ketchup, as well as the condition of the bottle.

Watch out for any off-colors or the presence of molds, as these are clear signs of spoilage. Overheated or expired ketchup may exhibit a typical brown color and off-flavors, resulting from the oxidation of carotenoids and lipids.

Perform a sniff test and be attentive to any unusual odors, especially a sharp sour scent or anything different from the typical ketchup smell, as it indicates spoilage. If you detect off-flavors or experience a slightly bitter after-taste while tasting the ketchup, it is likely past its prime and should be discarded.

For unopened bottles that have been stored for an extended period, a bulging appearance is a telltale sign of spoilage. This bulging occurs due to gas formation caused by microbial contamination. 

If any of these indicators are present, it’s best to dispose of the ketchup. Microbial contamination may have occurred, rendering the ketchup unfit for consumption.(1, 2)

Does spoiled ketchup have any adverse effects?

Consuming spoiled ketchup can result in food poisoning, leading to various symptoms such as headaches, vomiting, stomachaches, and diarrhea. 

Certain fungal toxins, like aflatoxin, can pose a particular risk to the liver, with early signs including fever, malaise, loss of appetite, abdominal pain, vomiting, and hepatitis. Severe cases of poisoning, however, are uncommon.

In addition, a decrease in appetite and nausea are typical indicators of food poisoning, typically lasting for just a day or two. If these symptoms persist or worsen, it is advisable to seek medical attention to ensure proper care and treatment.(3, 4)

How to Store Ketchup in the Correct Way?

To ensure the freshness and quality of opened ketchup, it is crucial to store it in the refrigerator at 40 degrees Fahrenheit or below. 

Bacterial growth accelerates between 40 and 140 degrees Fahrenheit, making refrigeration at a lower temperature essential for preserving the ketchup for an extended period.

Conversely, unopened ketchup can safely be stored at room temperature since it is a shelf-stable product. Additionally, freezing ketchup does not have any adverse effects, and there have been no studies indicating negative consequences from doing so. (4, 5)

What is the shelf life of ketchup?

Ketchup is a shelf-stable product that can be safely stored at room temperature for one or more years. However, once the bottle is opened, it is essential to refrigerate the ketchup and consume it within eight weeks to preserve its quality and ensure safety.

The microbial stability of tomato ketchup is maintained by factors such as its low pH level (below 4.0), pasteurization, and the addition of preservatives. The product undergoes several crucial heat treatments during its production process, which significantly contribute to its overall safety and stability. (5)

Are ketchup packets safe to use after the best by date?

The “expiry date” or “best before” date provided by the manufacturer serves as an indication of the period when the product is expected to be at its peak quality. 

Beyond this date, the food may not necessarily spoil or pose safety risks, but there is a possibility that its original texture or flavor could be affected. To extend the shelf life and maintain the enjoyment of coconut milk, proper storage is essential. (6)

Is it safe to eat expired ketchup?

Consuming expired ketchup doesn’t necessarily lead to sickness, provided it has been stored properly. Tomato ketchup, along with other tomato preserves like tomato paste, puree, and juice, is generally considered an ambient stable product.

The production process involves pasteurizing tomato paste (either cold or hot break concentrated), which is later combined with various ingredients such as starch, vinegar, spices, sugar, salt, and others. 

The mixture is then boiled and aseptically hot-filled or filled and pasteurized in a hermetically sealed bottle. Additionally, preservatives may be added to ensure stability. (5)

Other FAQs about Ketchup that you may be interested in.

Can ketchup packets go bad?

Benefits of ketchup

Can ketchup be left out?


In this short article, we provided an answer to the question “can ketchup go bad?” and the ways to find out its spoilage and methods to store it properly.


  1. Bjorkroth, K. J., & Korkeala, H. J. Lactobacillus fructivorans Spoilage of Tomato Ketchup. Journal of Food Protection, 60(5), 505–509. 1997.
  2. Kumar, Vishal & Kumar, Lalit & Kumar, Kapil & GOYAL, S. & Kumar, Amit & Jain, Garima.  Physico-chemical and quality evaluation of tomato ketchup during storage. South Asian Journal of Food Technology and Environment. 01. 250-255. 2015.
  3. BM Lund, SJ O’Brien, Public Health Measures: Food Safety in Hospitals and Other Healthcare Settings, Encyclopedia of Food Safety, Academic Press, 2014, 140-148.
  4. Kumar P, Mahato DK, Kamle M, Mohanta TK, Kang SG. Aflatoxins: A Global Concern for Food Safety, Human Health and Their Management. Front Microbiol. 2017.
  5. Rajchl, A., Voldřich, M., Čížková, H., Hronová, M., Ševčík, R., Dobiáš, J., & Pivoňka, J. . Stability of nutritionally important compounds and shelf life prediction of tomato ketchup. Journal of Food Engineering, 99(4), 465–470. 2010.
  6. U.S. Department of Agriculture. Website. Washington, DC. Food Product Dating. 2019.