Eggs is eggs

In December new food labelling regulations were introduced.
Which mean that my most important winter job is to find a way of telling customers exactly what's in our food. Or rather whether any ingredients from a list of allergens are involved anywhere.
I gave myself a deadline to do this.
End of January.
I started today.
I do have a question, though.
Do I need to write "contains eggs" after "Egg Mayonnaise"?
The law now demands it, but is there a better way of doing it?
Perhaps I should just insert the word "obviously".