Can bacteria grow in hot sauce?

In this article, we answer the following question: Can bacteria grow in hot sauce? We explain what capsaicin is, why bacteria cannot grow in a spicy sauce, and how to tell if a sauce has gone bad. 

Can bacteria grow in hot sauce?

Bacteria cannot grow in hot sauce! The antimicrobial properties of capsaicin, the substance responsible for the burning sensation, make chili, like other spicy foods, unattractive to bacteria that feed on plants and, therefore, safer for human consumption.

One in four people consumes chili daily. The diet of India or Latin American countries is often nourished by this type of peppers characterized by their spicy flavor. Researchers from the University of Washington have wanted to show that this particular flavor is due to these mature plants’ chemical defense to reduce the risk of a microbial attack.

In their work, the data of which is published in the journal ‘Proceedings of the National Academy of Science,’ the scientists analyzed chilies from seven different crops of the same type of plant, the ‘Capsicum chacoense hunz,’ from an area of 1,600 square kilometers east of Bolivia. In this area, these plants present a significant variation in the capsaicin levels, making it an ideal place to study the impact of microbial pathogens on the chemistry of this food.

Destruction of the seeds of plants

The ‘Fusarium semitectum,’ a type of fungus, takes advantage of the holes made in the skin of fruit or vegetables by different insects to infect the food and destroy its seeds before they can be spread by birds and contribute to their resettlement.

For these peppers, the greatest danger occurs before the seeds are dispersed, when this fungus can destroy a significant number,” explains Joshua Tewksbury, professor of biology at the University of Washington. “Both the fungus and the bird feed on seeds, but the fungus never contributes to their dispersal, it only kills them.”

The hot pepper acts as a defense mechanism. “Capsaicin does not stop the spread of the seeds because the birds do not feel the pain [produced by the spice] and therefore continue to eat peppers, but the fungus is quite sensitive to this substance,” explains Tewksbury, lead author of the study.

What the scientists found was that the degree of ‘Fusarium’ infection was doubled in the seeds of non-spicy plants. They also found that there were even more hot peppers in areas where the insect population was higher. However, in areas where fewer insects and the danger of fungal attacks were also lower, most plants had a lighter taste because they contained half the capsaicin compared to those where fungal attacks were more likely.

Capsaicin protects chili peppers and their seeds from a fungal pathogen that severely reduces seed viability […] These results provide strong support for the role of microbes in shaping the chemistry of the fruit in wild species, “conclude the authors.

Before there was a refrigeration system, eating chili was probably an adaptive response, especially in the tropics,” explains Tewksbury. “If you lived in a hot, humid climate, eating could be dangerous because virtually everything is covered in microbes, many of them dangerous.”

Chili peppers originate from South America, and from there they spread throughout Central America and the southern United States. The colonizers took this food to Europe, and from there, it went to Asia and Africa, where it is a prevalent ingredient in these countries.

In the north, any adaptive benefit from using chili could be much smaller than in the tropics because microbial infections from food are less common and food is easier to keep cold. 

Other FAQs about Sauces which you may be interested in.

Can sauces go out of date?

Can I freeze a jar of sauce?

How can I tell if a sauce has gone bad?

It’s very simple. I know that it is rare for a sauce to spoil, but it can happen; if you are not sure if it is good or not, better follow these tips.

When a sauce, whatever it is, is old, it has a very peculiar smell; it is not the usual chili smell, it is different, I could describe it as “sour.” If your smell is not so good and you prefer another type of test, take a good look at its appearance. Appearance is very important and can give you signs of the condition it is in.

Commonly, if a sauce is in bad condition, it will have mold, little green dots with some white hairs, if your sauce has this … THROW IT OUT! It is no longer good, and it is much better if you throw it away. 

Another way to know if a sauce is bad by its appearance is if it has small bubbles … DO NOT EAT IT! It is a sign that it is decomposing and, to avoid diseases, throw it away.

If it has been under the sun, stored poorly, or its preservation process was done wrong, it may spoil quickly, but if you made sure to keep it in the right place, it would indeed remain in good condition.


In this article, we answered the following question: Can bacteria grow in hot sauce? We explained what capsaicin is, why bacteria cannot grow in a spicy sauce, and how to tell if a sauce has gone bad. 

The short answer is no; bacteria cannot grow in hot sauce. However, if it hasn’t been stored correctly or if it exceeds way long its term, it is better to double-check the sauce before eating it. 

If you have any doubts, questions, or comments on the content, please let us know!


The University of Washington. (2008, August 12). Bugs Put The Heat In Chili Peppers. ScienceDaily. Retrieved September 7, 2020, from