That's ridiculous. Aunt Jemima is a brand name.
I once got [censored]ed out for saying "jerry rigged" when explaining something, because apparently it's offensive to Germans?

Nazi soldiers were called "Jerrys" by the Allied Forces in WWII. Then it was applied to German people in general. The rigged aspect is a result of Germany's history of exceptional engineering.
While I can see how a person from Germany would not want a Nazi-era term applied to them, that expression is actually quite a compliment on the technical skills of the person doing the "rigging".
As for the concept of racism, it boils down to this: Humans form societies of similar people in order to survive. When something is different we tend to be suspicious of it as part of our survival instinct.
That inherent suspicion earned the name "racism" when it is applied to our suspicion of people due to a difference in skin color. To that effect, all humans are "racist" as all humans are innately suspicious of different humans. I know most people will flatly deny this fact due to the negative stigma that has been given to the term "racist", however it is true, every single person on the planet is a racist to some degree or another. Of course, being a racist is not wrong as it simply means you are suspicious of things that are different, which is a healthy degree of caution to have. Where racism gets its bad rap is actually from a related but different human activity known as Discrimination.
Discrimination is the act of favoring one over another, which, again, is not inherently bad. Without going into theology, lets just say there are two theories of morality (good/bad) and they are Social Expectation and Divine Truth. In either case, the morality is predetermined and your discriminatory choices are graded as good or bad using whichever scale you and your neighbors subscribe to. When I choose to wear a helmet while riding a motorcycle, I'm using good discrimination from a logical standard, when I choose to make certain people ride at the back of the bus, I'm using bad discrimination by the moral standards we use today, but good discrimination from the racist standard that is a part of my survival instinct.
The mark of a civilized society is the ability to put the common good over one's own survival instinct. Civilizations must suppress some degree of their racism in order to avoid making bad discriminations against other members of society.