I have read around the forum a lot about this topic and I have seen a number of threads covering this topic, but I feel like I have some useful info and some questions regarding the ACRB goo results many people including myself have gotten.
I have been working with ACRB for about a year now, and it is the only plant I have ever extracted. I cannot compare to other materials such as MHRB. I will try to quickly give a rundown of my extractions and then a few thoughts and a question about the results.
At this point I have Mod Edit:No discussion of sourcing, Thankyou over the course of a year. The first in early spring of last year, and the last three during late fall or winter of last year/this year.
Batch#1- 2 kilos ACRB whole pieces( most pieces were at least 2" long, 2" wide, 3/8" thick)
Batch#2- 500gms of shredded root bark, much smaller pieces very thin and most under 1" long
Batch#3- same as batch #2 just ordered at a later date
Batch#4- same again, just a later date
The method I used to extract is similar to thick-lights tek, with only a few changes. I did 250gms at a time and did all my acid cooks and reducing done in a slow cooker. I never used salt either.
My first two extractions from my first batch of bark resulted in a clear goo from the room temp precipitation and even more goo from freeze precipitation. After doing 6 more extractions from the same bark, I finally came up with a method of using an extensive freeze precip in order to grow some crystals that were large enough to collect. The end result was still mostly amber colored goo though.
When I got my second batch of bark I went the same direction expecting the same results,( I don't mind the goo actually, it is difficult to work with, but the trip is sublime) this time though I got nice white fluffy crystals At room temp precip and only slightly sticky white crystals from freeze precip. It has been this way for me ever since, my last three batches of bark have produced nice clean crystals with little effort.
My thoughts on this,
#1 The first batch of bark I got may have been genuine root bark, since then I may have been getting trunk bark. The alkaloid content between the two is a bit different from my understanding and could explain my results. My first batch had a better yield even if it was goo, close to 3%, my last 3 batches have been consistently 2% yield.
#2 There is some kind of dramatic seasonal variation in either alkaloid or plant fat content. I assume the bark I purchase is pulled from many different trees and combined for shipping, so it is most likely a homogeneous mixture, and therefore unlikely that any one tree is the cause. I could be wrong on that it is just conjecture. Perhaps there is some part of the growing season that is not ideal for harvesting root bark?
I don't consider getting goo to be a problem, I am just truly curious to nail down the cause of such drastic results, from using the exact same process, with supposedly the exact same bark.
I have yet to see a general consensus here on the reason for these variations in results, and I would really like to see if it can be nailed down. Is it NMT or is it plant fats?