I have no chemistry knowledge, but after hours of reading and few extractions, i think i understood something. (or at least i hope so)
Thinking of an A/B tek:
Let's say sufficient pKa is reached and 99% of the spice is freebased instanly, or in few seconds.
Let's assume you are using a standard solvent: you know it works for sure and your pulling technique has always done its job before.
- We know that an excess with lye actually doesn't hurt the spice, nor the pulling process.
- We also know that heat of the solution or solvent increases yield, but can't make the difference between a 0,3% yield and a 1.5%.
- We know adding NaCl can only ionize more the solution, thus helping the pulling process.
- Somebody argue that tap water vs distilled vs non-ionized vs filtered is relevant, yet there is not strong evidence.
- Somebody argue that powdered mimosa is better.
The only problem with a low yield (like 0,200g from 100g MH) should be looked for in the prior steps to basification:
1) Bad MH.
2) Thick pieces of MH.
3) Bad exhaustion of the MHRB in the acidification step.
4) Not adding salt.
As far as my knowledge goes, you can find solutions for the steps before:
1) Nothing you cand do except buy a new MH.
2)
REMOVED powdered.
4) Add salt.
3) Nobody knows, some say to simmer, some to boil, some for 2 hours, some for 8 etc, some say acetic acid, some say Hcl, etc...
So this is, in my newbie opinion, probably the most important part of an extraction, because if the other variables, if applied, could only increase yield, the trick must be in the third one, which is not (at least for my researches on the nexus) deeply understood.
This is just a theoretical work that fits my level of knowledge on the topic, it could be complete bullshit.