To Freeze or Freeze Dry Before Ethanol Extraction

I work at a facility where we are trying to improve the quality of our ethanol extracts, both our shatter and sugar wax. I have found allot of good info on color remediation and winterization in the forums, but only a little bit in regards to freeze drying before hand. It seems like some people simply store material in freezer, and wash using subzero ethanol while others freeze dry first and then wash using subzero ethanol.

We freeze dry our dried flower first so we can collect the terps for reintroduction later. We wash in freezing ethanol but do not chill flower before wash after it has been freeze dried. Is this something we should be doing?

What are the advantages/disadvantages of freeze drying vs not freeze drying? Will freeze drying have any impact on initial color of washed solution? As in, will freeze drying promote more removal of chlorophyl during soak?


I have no constructive info but very curious to see what others have found in this regard. Ive always wanted to try running freeze dried material with C3 or C4. Can you share any pics of your extracts using freezedried material?

The only drawback of having room temp biomass is that it will warm up your Ethanol when they come in contact with each other. What temp is your ethanol staying throughout the run?


@Photon_noir has stated before that freezing of biomass seems to be more inportant than not
@cyclopath stated that freezing is not done by HIM so much
Can the both of you clarify ?
I freeze well -80C or i don t room temp nothing inbetween

For smokables like shatter and wax with EToH I’ve found it’s crucial to freeze your material. I’ve extracted at -65c withgood success on preserving color. How are you going to reintroduce your terps to shatter and wax?

We use a centrifuge to separate the terps from the hydrosol and misc matter. We then mix the terps with the crude after it has been almost run down fully. Then pour and do a final purge in the vac oven.

1 Like

Interesting…feel it retains the profile of the plant.

Sounds like you are doing it the right way for ethanol extracts. Definitely freeze your biomass as well as the container you are doing your extraction in, as well as any extra things that could add heat (such as a panda spinner for ethanol removal, or if you are using a cup 15 or somthing, consider running a batch of frozen ethanol through it first to get the whole thing cold) You would be amazed how much freezing everything as low as you can go will help with better color. The next thing I recommend for better color is to avoid excessive or any grinding if you can, will save you some extra chlorophyll in your extract.


Not really but I don’t think any extraction using ethanol does.

Fair enough, been my experience as well.

@Roguelab Lol! Ya gotta stop quoting me out of context, Man! :hear_with_hearing_aid:

When using DRY biomass, there is NO need to freeze it prior to extraction. In fact,
freezing dry herb prior to extracting can be detrimental to the extraction, since…
Cold resin glands fall off easier, AND
Frozen solid resin takes longer to dissolve, AND
Frozen trichomes condense water out of the air onto their immense surface area!

Dry herb has very little heat capacity. This is the inverse experiment to prove it to yourself:
Try freezing a dry cotton ball and a wet cotton ball some time. Then take them out of the freezer, one into each hand, and see how cold they are after 5 seconds! Notice how fast the dry one heated up?
That means dry herb will NOT warm up cold ethanol by any appreciable degree.
However, notice how cold the wet cotton ball stays?
That means ANY water that is warmer than the ethanol (condensed humidity ice is 0°C; way warmer than -80°C) WILL add a shit ton of heat to the cold ethanol!

For the next time you “quote” me:

“CHILL the SOLVENT! AND, do NOT chill the BIOMASS!”


Oh wizard of wizards thank you
Please check my last cry for help
An intersting thingy :grin::fist_left:


Speaking of dry what % of humidity of biomass are you thinking?

Since most folks don’t use moisture analyzers, @DocsCBD, my usual recommendation is at least 2 days with continuously moving air in layers no more than 12" thick, uncompressed, at less than 40% RH @ 75-79°F.