While reading through the usual posts about plume versus mold on a Facebook group of cigar lovers, I happened on a reply by Matt Alward that caught my attention. I reached out and asked if he would be interested in writing it up as a proper article. Matt is a microbiologist with good credibility to weigh in on the topic. I hope you enjoy it. -MDG
—
I’ve seen a lot of controversy recently, (and let’s be honest, does it ever go away?) on the topic of whether that white furry/powdery substance that occurs on cigars is plume (crystallized cigar oils) or mold. I thought I’d copy my so often voiced opinion on the issue as its own article.
Why does my opinion matter and who am I? Well, I am a scientist, a masters’ research in molecular biology, research in both microbiology and molecular biology in a fungal lab. Between finishing my bachelor’s degree and starting my master’s degree, I worked as an analytical chemist, so I feel uniquely qualified to comment on this with my thoughts carrying a bit of weight.
If you do a quick search, you’ll find a study by the friends of Habanos in which they had microbiologists look into plume vs mold. All of the cigars studied had mold. As a molecular microbiologist I found a few holes in that study, however it does highlight an important aspect to be aware of: there are strains of mold that live on cigars that may cause fatal infections. Having worked as an analytical chemist, and having taken many chemistry classes in the course of my education, I’ve learned enough to know that nothing will crystallize as perfectly as the spots on most ‘plumed’ cigars I have seen. Those are thriving colonies of mold that are producing fruiting bodies. If cigar plume does exist it would be not much larger than a pinprick point on a cigar. So, if your stogie looks furry, toss it out.

I’ve never seen a published scientific report about the Friends of Habanos study so I’m missing information I would normally use to qualify the data. Things like spore count or primers used for the PCR detection, for example. All I’ve ever read on said study has come from an article posted in a magazine which is intended to be a general reading publication, and not a scientific treatise. That is, most of the science is left out or glossed over to keep it interesting for the lay reader. The biggest flaw in the premise of the published article is that they found mold on all cigars, which isn’t terribly surprising since most any organic material (that is not autoclaved) will have mold spores. I’m sure I could take a stick from my own humidor, wipe it on a growth plate, stick it in an incubator, and grow mold. Spores float in the air and settle on anything. So, it is likely that everyone’s cigars have spores.

Organic crystals of such a minute amount as a true plume (again, if it exists) would be quite fragile, and in my opinion very difficult to positively identify. My understanding of the study is that they scraped the spots into a tube of PCR mix, and then analyzed it for a genetic analysis of mold. Without giving everyone a quick rundown of how PCR identification works, it would be difficult to explain first, how they got results, and second, why that doesn’t prove that plume exists. I feel like it’s a case where you could find whatever you look for, because the oils will be in the cigar and any analysis to look for organic crystals will find the oil. Again, without going into an in-depth explanation of how analytical chemistry methods work (probably a GC-Mass Spectrometer), it is hard to explain why they wouldn’t find something by trying that method.
So: they set out to disprove something. and in my opinion, they were bound to find whatever they were looking for.
Now, do I think plume is possible? Theoretically, yes. I wouldn’t expect to find plume on a cigar with a Connecticut wrapper. On a dark wrapper cigar such as a Cameroon or a Maduro, I could in theory imagine organic compounds would crystallize as any residual solvents (ammonia or other volatiles that are left in the tobacco that dissipate as it ages) evaporate out. However, as I stated above: it wouldn’t be circular, it wouldn’t be even, and it wouldn’t be fuzzy.
If you want to see how organic compounds crystallize, I suggest looking up NileRed on YouTube. He has fantastic organic synthesis videos, and a big part of that is re-crystallization purification. Never do the compounds look furry or concentric once dried.
About the Author:
Matt Alward is a molecular microbiologist who has a passion for fine tobacco products. He has worked for Fortune 500 companies as a microbiologist, analytical chemist, and lab technician. His academic research has focused on the genetics of CRISPR/cas9 in Neurospora crassa, guanine-quadroplex blocking of DNA mismatch repair, and identification and characterization of a novel SAMase coliphage gene.
1 thought on “Plume? Unlikely.”