This being in the context of extracting from plant material means that DMT will be present in its natural salt form, or rather we have protonated cations and a selection of organic and inorganic ions in the cellular matrix. In that sense the main reason to add an acid would be to free up any DMT that happened to be bound to tannin, so this decision depends, to a certain extent, on the plant material concerned.Interesting, so this does mean you would recommend adding an acid to these cold alcohol soaks? If so, which acid would be the best choice?
EDIT: And am still unclear as to whether iso or ethanol would be better for soaking up orally active DMT, if any? Tnx again for all the help!
I still haven't tried the hot vodka extraction for anything other than acorns but I still get the feeling it would be worth trying with mimosa bark, followed by precipitation of the tannins with lime. The resulting tannin-free tincture (it being reasonably safe to assume that the method is effective in removing mimosa tannin) can either be left as a solution of freebase or neutralised with some kind of edible acid. The latter option is probably more suited to subsequent ingestion.
The reasoning of this last point also extends to harmalas in that having an ostensibly food-grade solvent (ethanol) keeps some options open that iso would hinder, as well as harmalas having better solubility in the ethanol - although I can't definitively say that extends to any given salt form since there isn't an enormous amount of data available.
If you're going by the price, bear in mind you'll likely have to use a larger amount of iso for a given quantity of harmalas to dissolve, and this larger amount would take a longer time to evaporate - although this may be less relevant for an arbitrary, relatively large volume used for extracting plant material.
There are also the qualitative differences in extraction which you noticed between the two alcohols. You'll have to weigh up how much the clumping effect is disadvantageous in comparison to the seeming benefit of the clearer extract, for example.
If you already have a big bottle of iso you might as well use it. Vodka is relatively cheap where I am, or at least the cheap stuff is - how is it in your part of the world?