Boiling pot question

I do not have photos to show and I kick myself for forgetting this. My question has to do with color changes.

When I go to harvest the D9 isolate off the cold finger in my rig then I must break vacuum for several minutes while everything is still hot and in process. The compound in the boiling puddle VERY quickly begins turning orange brown and darker as I harvest the goodies. Then… it gets wierd…

When I pull down to vacuum again to proceed with the next collection, slowly and surely the darker brown/orange aspect of the compound begins to fade and ultimately returns to the hue, more or less, that it was when the distillation commenced. I will grab some photos of this. This phenomena would be impossible to catch if not for running already very clear compound. It is bizarre - I can look in the pot with disgust at how much color change happens and so rapid, yet placed back under a vacuum of ¾ micron and typically say 135°C nominal on the boiling flask the compound returns to the very light yellow/brown I started with. I cannot detect anything being transfered up to the cold finger that might account for this.

Why does the compound turn darker just out of vacuum and hot and then substantially return to the original color? I have been running multiple tests with this hoping that it might reveal clues about color change in general but would like to hear opinions. For the sake of this post assume the color change as described is taking place and that it is not a trick of lighting or some such thing.

1 Like

Intersting
I have broken vacuum several times below 140C and not see Any change
Above 140C breaking vacuum red came quik
But then My vacuum was way higher so was My volume
Since iT doesn t sound like a reaction of Some kind
Maybe a light refraction deu to the sudden administration of air compounds ?
Great Puzzle thou🤗