High terpene extract coming out dark

frazierk said:

I have been playing around with separations a little bit but the high terpene portion (HTE, HTFSE, sauce, whatever you want to call it) always comes out dark and pretty viscous, and I can't figure out exactly what to do to get a lighter and less viscous extract.

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I pack columns with really high quality dry trim/larf that is only a week or two old, and sticking them in the deep freezer over night. I use a 70/30 n-butane/propane mix chilled on ice water then injected through a coil om a dry ice/isopropanol slurry. I am having to push a lot of the gas through the column by injecting nitrogen through the chiller coil at 50 PSI or else it wants to stay in the column.

I am currently not dewaxing or using a molecular sieve.

This is the only time I see any extract I make come out dark. When I make pull 'n snap or shatter it always comes out looking gold. I use the same process except I pull a muffin when making pull 'n snap/shatter and pour when making separations. What might be causing the dark color to come through with the separation but not with the pull 'n snap/shatter?

[URL=https://www.icmag.com/ic/picture.php?albumid=73428&pictureid=1782526&thumb=1]View Image[/url] [URL=https://www.icmag.com/ic/picture.php?albumid=73428&pictureid=1782528&thumb=1]View Image[/url]

I have come up with a few possibilities:
- The chiller coil I am using isn't long enough as it only has a single layer of coils and isn't getting the gas cold enough.
- I could use a gas mixture with more propane or some iso-butane.
- Gas is contaminated with water (however I am seeing no nucleation in shatter/pull 'n snap).
- Not dewaxing fully (does a single solvent dewax help remove dark color?)

What do ya'll think?

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Digital Man said:

Just think ........... it wasn't that long ago (2 years ?) that nobody cared if it was dark or not .... as long as it was loud and potent. Welcome .... to the machine.

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frazierk said:

I have been playing around with separations a little bit but the high terpene portion (HTE, HTFSE, sauce, whatever you want to call it) always comes out dark and pretty viscous, and I can't figure out exactly what to do to get a lighter and less viscous extract.

View Image View Image View Image

I pack columns with really high quality dry trim/larf that is only a week or two old, and sticking them in the deep freezer over night. I use a 70/30 n-butane/propane mix chilled on ice water then injected through a coil om a dry ice/isopropanol slurry. I am having to push a lot of the gas through the column by injecting nitrogen through the chiller coil at 50 PSI or else it wants to stay in the column.

I am currently not dewaxing or using a molecular sieve.

This is the only time I see any extract I make come out dark. When I make pull 'n snap or shatter it always comes out looking gold. I use the same process except I pull a muffin when making pull 'n snap/shatter and pour when making separations. What might be causing the dark color to come through with the separation but not with the pull 'n snap/shatter?

View Image View Image

I have come up with a few possibilities:
- The chiller coil I am using isn't long enough as it only has a single layer of coils and isn't getting the gas cold enough.
- I could use a gas mixture with more propane or some iso-butane.
- Gas is contaminated with water (however I am seeing no nucleation in shatter/pull 'n snap).
- Not dewaxing fully (does a single solvent dewax help remove dark color?)

What do ya'll think?

Click to expand...

Gray Wolf said:

I suggest trying alcohol and dry ice to get your injection temperature below -30/50C.

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Gray Wolf said:

Dark colors suggest C-30 molecules, because the cannabinoids are white to light yellow and the mono/sesquiterpenes are mostly colorless.

I suggest trying alcohol and dry ice to get your injection temperature below -30/50C.

The C-30 anthrocyanin plant pigments also exhibit the Beers/Lambert effect when it comes to light refraction and color, so the beaker will always be significantly darker than a thin film.

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Thomas@LRL said:

That isn't true. The majority of the people processing two years ago didn't know what factors were impacting the color or how to avoid initiating such a change. We have learned an awful lot about the associated plant biology and chemistry since then and can now deliver more accurate criticisms.

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Thomas@LRL said:

Is there a way to improve the color in post processing via carbon or bleaching clay? I know that Carotenoids degrade at 260C but that's a bit high temp for cannabis.

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