Not sure if this is the right place to post this, but....

So i've been extracting from some ACRB using sunflower oil, vinegar and sodium carb using a q21q21 style tek.

I've started noticing that after salting the oil, and then reducing the combined saltings, i get the usual deep orange looking solution. When i store this in the fridge for a while it starts precipitating something.

At first i thought it was contamination from fats or something in the oil but after reducing the solution further over an aromatherapy burner the whole solution become filled with the same precipitate. It left a sticky yellow/orange goo around the rim of the glass container as it was being reduced over the burner.

So my question is, is it possible for NMT to precipitate out in a fridge(not freezer) in this way? Has anyone else who has extracted from ACRB (and produced an acetate solution) noticed this sort of murky floating stuff as the solution is reduced further ?

Has anyone else experienced this ? Attached is the best pic i could make of it.

I doubt it would precipitate in salt form, have you frozen the mix so you can remove the last bit of oil?

nope, but i filtered several times through tissue paper till there was only the tiniest film of oil on the surface (barely visible). It may just be contamination from reusing the same oil so many times though. I've transfered it to a 15ml bottle and left that in the fridge over night so that all the sediment just sinks to the bottom. The top layer is clear and orange now, so i will do a test at some point to see if the stuff on the bottom is more potent than the stuff at the top

If this is contamination, would a sodium carbonate wash before salting prevent this from happening in future? I used sodium carb as my base so I didn't see why this would be necessary.

I see, maybe its a soapy bi-product.
You should freeze after salting to get that last bit of oil off. It is incrediblt stubborn and will mess your final extract up if it stays in.

I'm using a sep funnel and filtering the saltings through 4-folded tissue paper which does a pretty good job of catching any oil, but i'll give freezing a go on the next round. Do you just wipe off any oil once the salted solution is frozen ?

My bet is on the soapy contaminants, because come to think of it, i've had to chuck quite a bit of emulsified junk that builds up between the oil and water. I tried freezing that stuff to reclaim the oil, but it would not separate.

Pour as much off as possible and pipette off the rest. Seems youve got the set up good as it is but it just takes a tiny bit of oil to fudge things up at the end.
Iirc the key to using oil is no vigorous mixing with the base mix and make the pulls quick and at room temperature.
Will be interested to see how this develops.