Here’s the chemistry behind marijuana’s skunky scent

Researchers have last but not least sniffed out the molecules behind marijuana’s skunky aroma.

The heady bouquet that wafts off of new weed is truly a cocktail of hundreds of fragrant compounds. The most outstanding floral, citrusy and piney overtones appear from a frequent course of molecules referred to as terpenes, suggests analytical chemist Iain Oswald of Abstrax Tech, a personal company in Tustin, Calif., that develops terpenes for cannabis products (SN: 4/30/18). But the resource of that funky ganja observe has been tricky to pin down.

Now, an assessment is the initially to establish a team of sulfur compounds in cannabis that account for the skunklike scent, researchers report November 12 in ACS Omega.

Oswald and colleagues had a hunch that the perpetrator might have sulfur, a smelly factor located in hops and skunk spray. So the group started out by score the skunk aspect of flowers harvested from a lot more than a dozen kinds of Hashish sativa on a scale from zero to 10, with 10 currently being the most pungent. Upcoming, the team created a “chemical fingerprint” of the airborne parts that contributed to every single cultivar’s one of a kind scent making use of gasoline chromatography, mass spectroscopy and a sulfur chemiluminescence detector.  

As suspected, the scientists observed little amounts of quite a few aromatic sulfur compounds lurking in the olfactory profiles of the smelliest cultivars. The most dominant was a molecule identified as prenylthiol, or 3-methyl-2-butene-1-thiol, that offers “skunked beer” its infamous flavor (SN: 11/27/05).

The sulfur compounds have been observed in mother nature, but by no means prior to in cannabis, claims Amber Smart, an analytical chemist with Medication Creek Analytics in Fife, Clean., who was not included in the analyze.

Oswald was shocked to find that prenylthiol and lots of of the other sulfurous suspects in cannabis share structural similarities with molecules located in garlic. And like these alliaceous analogs, a little goes a very long way.

These compounds “can be in incredibly very low concentrations on the flower, but nonetheless make a enormous effect on the odor,” Oswald states. The sulfur molecules are most plentiful in cannabis flowers when they reach maturity and all through the curing approach.

Smell psychologist Avery Gilbert of Headspace Sensory, a startup firm in Fort Collins, Colo., that specializes in quantifying the numerous scents of hashish, is excited to see the molecules additional to marijuana’s chemical repertoire. “The spectrum of cannabis odor is just amazing,” he states. “I consider it beats the pants off of wine.”

The discovery of prenylthiol in cannabis, Gilbert claims, is the initial phase to masking its nuisance odor — or maximizing its perversely enjoyable stink.

Prenylthiol has a “polarizing scent,” Oswald suggests. Whilst numerous people today believe it reeks, some hashish people will shell out best greenback for skunky grass, which some contemplate an indicator of top quality.