A "little more pop" means a little more exciting or interesting. It can apply in a variety of contexts: clothing, room design, color choice, food, and so on. "That new wall color makes everything in the room pop."

Without context, I'd say that they refer to something that makes the flavour stand out, for example what happens when you drink bubble tea and there's the drink flavour plus the bubble flavour that "pops" when you eat them. Hope it helps!

If some 'has a pop to it's means it has a strong colour or flavour to it. So the food or dish probably has a stronger flavour to it.