During ServSafe MN training, we often discuss stories of food poisoning incidents blamed on tainted mayonnaise in potato salad, sandwiches, or dips. Mayonnaise is widely believed to be highly perishable and demands additional precautions when utilized in food production. If you investigate further, you’ll find that it’s often not mayonnaise that has caused a foodborne illness. More often it’s other ingredients that have not been prepared to ServSafe training standards.
ServSafe MN Training and the Mayonnaise Myth
Commercially produced mayonnaise is loaded with acids and preservatives, so it generally does not spoil quickly. Refrigerating mayonnaise is typically recommended. However, the recommendation is more about diners’ taste preferences than creating a food safety hazard. There are even some unverified claims that adding mayo to dressings, and cold sauces can extend the life of those products. These claims are attributed to the acids and preservatives in commercially produced mayonnaise.
To be clear, ServSafe training does not refer to commercially processed mayo in this discussion. If you make your own mayonnaise in your restaurant, you will likely use raw eggs. You will also likely not add as much acid and preservatives as your standard store-bought mayo. We strongly recommend treating in-house mayonnaise as a volatile food product and always keeping it under refrigeration.
If it’s not the mayonnaise that causes food poisoning, why do common dishes that contain it make people ill? Ingredients such as cooked potatoes, pasta, and vegetables are not shelf-stable. Cooked potato dishes are, in fact, highly susceptible to bacteria growth. Leaving a potato or pasta salad at room temperature for an extended time will create a health hazard for anyone who consumes it. Many potato salads also contain cooked eggs, which are incredibly susceptible to bacteria if not refrigerated properly.
Cross-contamination Is Frequently The Culprit
We have also heard mayonnaise blamed for food poisoning incidents that have occurred as a result of eating at a buffet-style event. Cross-contamination during food preparation or service directly causes the onset of these illnesses. Cross-contamination occurs when a utensil is dipped into another dish on the buffet or when the mayo spreader comes into contact with meat proteins and then is returned to the mayonnaise dish. In these cases, it is highly likely that bacteria have contaminated the mayonnaise. While that mayonnaise may not need refrigeration, any bacteria introduced into it will grow at room temperature.
The bottom line of the ServSafe training is that it is crucial to avoid cross-contamination and handle every ingredient correctly when using mayonnaise in your establishment.
