I see no one has replied. I don't have kids myself, but I do have little brothers. And my mom's rule is that she always makes them try things. Even if they tried it before and didn't like it, tell them they need to take one bite and try it, or they can't have dessert/whatever. Taste buds change, especially for kids, so you may find they start liking things they used to hate.
'Life begins at the end of your comfort zone.' -Neale Donald Walsch