I presume that birdfoods have a quicker leakage of "attractors" due to their texture being courser than milk protein or fishmeal baits.with the outside of the boilie being rougher,this gives more surface area for attractors to escape from...having said that,I finely grind most of my birdfood ingrediants,and [censored] the baits with a boilie needle several times if I think I need a quicker release of attractors.
Bear in mind that it is not just flavours that catch fish, but the bait mix should be attractive in it's own right,eg;milk proteins and certain birdfoods,and fishmeals.
I see that no one has mentioned steaming their balls

,but I believe Mitz does or has done. Any thoughts on this?
Thinking back,I believe that the only reason for boiling paste baits (boilies) was to give them a HARD SKIN ONLY,to deter nuisance fish.Maybe it's time to go back to basics and return to trout pellet paste, or sausage meat paste..is purina still available?