..without careful analysis, how can we say that it isn't largely tars/resins in olympus mon's photos, rather than tannins..but certainly tannins can contribute to nausea..
the OP is largely an oral ingestion issue, whereas acacian's query relates to extraction..
in acacias i don't think tannins bind to alkaloids, cause problems etc..
the most common acacia class of tannins (condensed tannins) are Flavan,3-4-diols, which which heat and acid turn into flavonoid like anthocyanadins..
as for hydrolizable tannins, i don't know that these are common in acacias (or mimosas) ..they break down into gallic and similar acids with heat/water..
also the often parroted 'tannic acid' has never to my knowledge been reported in acacia or mimosa..
acacia tannins are generally more like relatives of flavonoids..
i'd just like to see more science on this issue, rather than here say..
ps. acacian, tars/resins can become soluble/solid depending on fine level of pH or heat..this will interfere with extractions if simply following a formula