Many things affect that, though. Someone in a constant state of anxiety and stress is running on adrenergic circuits instead of dopaminergic, and thus will probably like the taste of poppy seeds, because the minuscule amounts of opiate alkaloids will make an ever so slight dent on that adrenergic activity and allow dopaminergic activity to dominate.
It’s a similar story for coffee, but there is a lot of variability both in coffee and drinker. Someone with a high activity MAO-A gene variant will clear dopamine and other neurotransmitters from the brain more quickly. Darker roasts contain more MAO-A inhibitors, and so they are more commonly preferred by people with such gene variants.
Same goes for MAO-B; inhibitors for it are more likely to be found in lighter roasts with floral overtones.
