Is there any benefit to filtering the extract at room temperature?. Waxes and oils might cling better to the filter while they solid/cold.
I haven't tried to perform the final filtering at lowered temperatures, perhaps after the initial gunk removal I could transfer the extract directly into a final filtering setup while still in the freezer. At -10F it might take awhile to gravity flow through a 1 micron filter but could be worth a try.
Kinda torn on this one... ethanol does a good job of suspending oils in solution ( it is a solvent). Seeing that colder temps do make some oils less miscible in solution does allow for separation to occur and filtering better. When doing the heated reduction, I see oils form again ( after cold filtering) on the surface and also on the extract/bowl contact surfaces.
Only method I havent tried yet is "super cooling" with dry ice to see if anything else will drop out of solution. Im wondering just how many different forms of oil do exist in a NET extract and if removing all of them reduces the flavor characteristics of what we are extracting? Are we trying too hard to remove the "gunk" and loosing some of the flavors in the process? no telling... maybe some intense experimenting is required to determine if it is detrimental...
I've noticed that on average VaPer blends seem to yield more oil/gunk than other types of tobacco, for me they're the only extractions (
so far), that have yielded visible oil
after the freeze filtering step. I haven't freeze filtered at temperatures lower than -10F so can't really say if significantly lower temperatures would be more productive or not but
suspect they would. I know that my regular freezer (
a side-by-side refrigerator/freezer), set at +5F doesn't work as well as the deep freezer which is set at -10F and that's just a 15 degree difference. As with sub-micron mechanical filtering I'm sure there is some point where flavor could be affected by removing too much gunk but so far I haven't been
able to breach that boundary. The nearest dry ice for me would be an hour and a half round trip so I doubt I'll be experimenting with it anytime soon.
the fuzz might help, but you'd also probably waste more liquid as it probably would absorb more of it? i also don't think it's a good idea to squeeze the filter to recover more liquid as you might force particles out of the filter that were already captured.
I use a mechanical filter holder W/feed reservoir so the surface area of the filter felt is less than 2" in diameter, not much solvent loss with that small of a filter likely around 2 - 3ml which is about what I lose to a full coffee filter. I'm not worried about catching particulates at this stage only coalesced oils, resin and wax, the final filtering stage will take care of any particulates. You're right, definitely can't squeeze the filter or I'm sure the gunk would ooze through.
i have tried two different coffee filters i have. one is a traditional cup style filter and the other is a cone style filter. what i've discovered is the cone style coffee filter seems to filter better. i noticed that the liquid takes almost twice as long to go through compared to the cup/pot style filter. if it takes longer it must mean it's doing a better job filtering. i took both filters to a light bulb to see which had less light visible, clearly the filter i suspected was doing a better job shows less light.. another thing about these cone style filters is there is a crease/fold which also seems to help trap some of the particles, they're also more paper-like than the other softer filters which are more like thin towel paper.
I hadn't really thought about looking for coffee filters with better retention properties, definitely something I can research. I had thought about using 11 micron filter paper (
11 cents each), but I believe the pasty gunk would simply clog it too fast.
