This has all been based on what I've observed, not through any angling literature either, I find it to biased.
Original theories on amino's was carp would recognise a good balanced bait over what used to be termed a **** bait.
It doesn't stack up in my opinion, there are a number of problems with this theory.
Why would carp become so obsessed with eating peanuts, even to the brink of damaging their own health, if they knew what was good for them or not.
Why were scientists able to poison so many carp around a certain facility with laced poisoned pellets, if carp could tell the difference.
There's loads of examples of this, trout pellets, Peanuts, Tigers, maggots in fact anything that is provided in mass.
Plus it begs the question,
What is feeding triggered by?
What is a feeding stimulator?
What is attractive to Mr/Mrs Carp
Like I said before, building a good balanced bait can only benefit our quarry, or will it, seeing as they get all of what they need naturally.
Airborne flavours work differently to waterborne flavours, and a lot of what you smell albeit from a bag of boilies of a bottle of flavour had very little baring on the attractiveness to fish, which is why I look at bases.
Oils, many would have you believe there is no way a fish can detect these, but these oils are detected in a number of different ways, through the nostrils and through the skin.
Salt
I believe salt shouldn't be used, there's enough in fish meals and other substrates as it is. Adding salt to your particle, if you have to do it, make sure you dilute it in water first, because raw salt burns fish.
If you think your salt is dissolving in water once you've stuck it out, them believe me not all of it does, it kills vegetation where it lays, and once its in a water body it never comes out again as it doesn't evaporate.