I've done many extractions on mhrb and acacia and this is the first time I've come across this problem, when I added the salt and then the lye, the base foamed up and there's a head like a pint of Guinness on top of my base that I can't shift, Ive tried more salt and more lye but it won't go, looks like there's bits of white fats or something foating in it as well. Does anyone have any idea what it is and how I can shift it. Thanks

One explanation would be that you added too much base and the fats saponified (forming a soap) which then bubbled.

You can try slow mixing and heating over long period of time or removing the foam mechanically (with a scoop perhaps) and leaving it to flatten (it will eventually). You can extract your mother liquor in the mean time.

This is one of the reason I do A/B instead of STB extractions: filtering the liquor to remove fine solids that can be trapped in foam, avoiding the emulsion problems and being able to de-fat before basifying the mother liquor.

Hi blue magic, I did the a/b and filtered all the bark out so it's not that, plus it's not really a foam it's like a cream layer you'd get forming on a pint of whiskey with white bits floating about that looks like when milk curdles, I'll try the ultrasonic bath to wee if I can break it up but other than that I've not seen out like it before, when I shake and roll the bottle it reminds me of shaking a bottle of coke where it fizzes up

I had similar problem. I poured the mix over in two different jugs and filled up with double amount of water and let them sit with heat for sometime. Then it was gone.