IME, white DMT crystals get reddish with exposure to moisture, whether it's humidity in the air or "dried" herbs for the changa that probably still have some amount moisture in them and move to the DMT - never seems to hurt the effects though.
I plan on doing some testing in near future doing changa evaporation in a vacuum with desiccate to see if my suspicions are right that it won't look as red.
Do you know what the relative humidity is where you're evaporating?
Also, like Void mentioned, 1:.3 DMT to harmala ratio works out a little nicer. My first batch of changa was 1:1 like yours and it worked fine in general, but there were some nights I would make a session last for hours by repeatedly hitting the changa and after an hour of that I was wishing for enhanced herb with DMT only. Still a wonderful experience, but the next day I felt harmala hungover.
An affinity to entheogens that bring me to full submission,
A thriving esoteric greenhouse, I do envision