And here you have raised very pertinent additional points.
Any ingredient in a boilie is denatured, or liquids evaporate as they are boiled, less so if they are steamed.
By denature, the food value is reduced, the protein level is lowered, and enzymes 'killed', even vitamins and minerals are reduced, especially those on the outside skin of the boilie. The inside of the bait may still not be 'cooked' on short boiling times*, as the full temperature takes time to get to the middle. So the only part of the boilie that still contains fully effective or as you nicely describe it, beneficial effects is the middle.
The best way to get these liquids to continue working effectively is to soak or glug the baits after boiling.
You can add these liquids to your spod mix, your particles, your powdered groundbait, your pellets.
I don't know if anyone remembers the days of the CarpWorld/Nutrabaits Lac Fishabil trips, but Bill Cottams favourite mix I think was a bucket of birdfood, boilies crushed and whole with added Nutramino, Multimino PPc and condensed milk.
This is where you have different effects in water, the solubility of the liquid, how it mixes in the lake. Some liquids will spread out across the lakebed, others will cloud lakebed to surface.
The 'hope' is that the carp will follow the reverse track of the water current if any down to the source, and it creates a spot to investigate.
*My aim when making my own bait was to have a solid skin, but a paste middle.