Although it is true that there are no real health risks associated with microwaving mayonnaise, it might be a good idea to avoid doing this because of the fact that it will lose much of its texture, becoming quite watery and unappetizing.

While the chances of this happening are small, there is still the risk of salmonella bacteria forming in the mayonnaise so you will probably want to avoid heating it up this way.

There is a general loose taste to mayonnaise once it has gone through the microwave, so you will need to make sure that you do everything in your power to avoid this because of the fact that it essentially makes it inedible and very unappetizing.