I am wondering if there is any way to test if DMT has oxidised. I also understand that there is a tek to 'de-oxidise' DMT. Any information is appreciated.

I believe DMT oxide is insoluble in acetone based on work from Brennendes Wasser.

A lot of us don't think DMT oxide is a thing we usually get. Most of the time the colors/oils are just DMT polymorphs (DMT interacting with itself and taking on a different appearance). Calling that DMT oxide is a broad miss-conception I think.

To "reset" the DMT appearance you can do a mini A/B with gentle conditions during the base step (pH not above 12 and no more than 8% ionic strength). If you search the forum you can find successful conversion of oil to xtals this way.

I think some people added Zn during the mini A/B. The Zn does nothing and is not necessary to recover DMT xtals from the DMT polymorph goo. I think there was a miss interpretation that the Zn was reducing DMT oxide to DMT (which it would IF starting with DMT oxide), but in reality the A step was just breaking up the starting DMT polymer (bubbles are not a sign of reaction, they happen when Zn is in an acid I believe).

Yes.
Zn + CH3COOH -> (CH3COO)2Zn + H2

Barker SA, Monti JA, Christian ST. Metabolism of the hallucinogen N,N-dimethyltryptamine in rat brain homogenates. Biochem Pharmacol. 1980 Apr 1;29(7):1049-57. doi: 10.1016/0006-2952(80)90169-0. PMID: 6770869.

“In order to further identify DMT-NO, two additional solvent systems were utilized [chloroform-methanol-NHsOH (conc.), 60:10:1 and n-butanol-acetic acid (glacial)-water, 8:1:1]. The N-oxide was also identified by reacting the eluted sample from the thin-layer chromatography plates, corresponding to the Rf for DMT-NO, with zinc and acetic acid. The reduced N-oxide was rechromatographed in the previously described solvent systems and identified as DMT.”

Awesome guys. Thanks for your replies.