system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 - How can a food have an aftertaste? Why do some foods not have one?
gpt
certain foods have molecules that "stick" in your tongue and taste buds better. spicy sticks well, so do oils. 

mixing oil /fat into something is well known to preserve and transfer flavor better (think mayonaise or oil and vinegar in a sandwich.)