Does anyone know how long does it take for the alkaloids to be absorbed in the stomach?

I have tried ayahuasca twice so far. Chacruna the first time and Chaliponga the second. The first time I only ran the liquid once through a cotton filter, vomited within just 10-15 minutes and the nausea lasted a whole 2-3 hours. The effects were very mild, nothing more than faint color trails. The second time I filtered well, let the brew in the fridge over night and only drank the clear liquid from the top. I made 4 cooks of 3 hours each using 50g of Chaliponga and some citric acid. The liquid was reduced to 200ml, of which I made two doses, first of 20ml and second of 25ml, the liquid was very clear, no trace of any gunk, just clear wine red liquid. My stomach managed to take the first dose but I did not break through. An hour later I took the second dose, the nausea set in but it was much much milder than that of the first experience. I struggled to keep it in but ended up vomiting 30-40 minutes later, but still did not break through. So I was wondering if it could be because the goodies didn't have enough time to be absorbed before I threw up.

I suspected the leaves to be weak, but I did the iso tek on the left over brew, which didn't go well, but I assume the isopropanol still must have absorbed some amount of actives. I then tried A/B with naptha and still managed to extract over 1% of pure white crystals (I suppose iso took care of all the fats, the crystals were the whitest I have ever had!).

So, could anyone tell me if vomiting too soon is the problem?

What about harmalas? Are you sure you're taking enough for proper MAO inhibition? What and how are you preparing it and when are you taking it?
I assume you mean by breakthrough a full on experience, usually the term is specific for the smoalked dmt experience.

I tried pharmahuasca once and took 120mg of harmala freebase (harmine/harmaline mix). That was sufficiently strong and I had a fairly intense experience. With chacruna I also drank a sufficient amount of caapi, but don't remember the exact dose. With Chaliponga I took harmala freebase, 160mg of harmine/harmaline mix. The harmalas were strong enough, I could sense it! Perhaps breakthrough is the wrong term, but it felt like seeing things from behind a curtain, only CEV's and those too were very faint.

Early purging may diminish the experience yes. this hasn't happened to me though, even when once i purged 20 mins in but it was a big dose.
The absorption happens in the intestines, sometimes the liquid might just sit in your stomach until you purge so very little absorption will happen. I see people recommending eating something with it to induce digestion

7 g chalipanga or 10 g chacruna should be plenty strong, assuming good leaf (but there used to be chali that was overwhelmingly strong at 3 g). That's like 100 mg DMT.

120 mg harmalas seems low, I go for 200 mg.

An early purge can reduce the intensity.

I've read elsewhere on the forum that the gunk also contains a significant amount of actives, so the clear liquid on top may have been weaker as well. I'll try again with a higher dose of Harmalas and see if that's the likely cause.

The gunk might cause you to vomit much sooner.