Tobacco aging: 'bloom', yeast, rings and oxygen

Published by @kmbnrn on 2017-08-23


Here’s how all of this started. I hate Balkan Sobranie. I bought some tins of it and opened the first tin on October 27, 2014. Tried it - and just couldn’t enjoy it. Left it sealed in a Ball Mason jar and sold my remaining tins. So tonight, while looking for a tobacco to smoke, I pulled out the jar of Balkan Sobranie and thought “what the heck? I’ll try this again.” So when I opened the jar, the tobacco was covered with what I know to be “tobacco bloom,” not mold. Then I lit up a bowl and WOW!!!! This stuff is amazing! Sweet, ripe, fruit, light though - not the deep tangy flavors of my preferred Virginias.

Here’s where the science comes in. My son is home visiting, and he’s a research biologist working on his Ph.D. in Human and Molecular Genetics at the top genetics research facility in the country, if not the world. He took one look and said “I can tell you exactly what that is.” Not only is he home, his original tabletop microscope is still here. (Apparently even a $500-$1,000 microscope is a joke for someone sequencing and artificially rearranging DNA for his job, so we have a nice microscope sitting here collecting dust). Anyway - he took a piece of the tobacco, prepared a slide, and showed me exactly what was on the tobacco:

  1. Sugar Crystals
  2. Yeast. Specifically S. Cerevisae, also known commonly as Budding Yeast.

Then he explained the biological processes taking place in the tobacco from the time it was tinned until opened and then ultimately smoked.

  1. Tobacco is sealed in the tin and yeast rapidly consumes all of the oxygen in the tin. He figured that could happen in mere weeks.
  2. the yeast eats the starches and complex carbohydrates in the tobacco, leaving behind the sugar crystals AND Aromatics. No - not aromatics like the goop added to aromatic tobacco, but “carbon rings” called aromatics because they do in fact have distinctive taste. That process continues until the yeast population is saturated and the reaction mostly stops.
  3. you open the tin. If you smoke a bowl right then you’ll get a mix of the tobacco, with its natural starches and sugars, plus the sugars and aromatics created by the yeast.
  4. the tin, once opened, re-introduces oxygen to the system. The oxygen oxidizes the aromatic rings, modifying their flavor profile. Maybe a little, maybe a lot. Maybe for better, maybe for worse. Just depends on what the individual doing the smoking seems to prefer.
  5. the oxidized carbon rings are more stable than the original carbon compounds, so once they’ve oxidized, they’re done and no amount of aging/storing will convert them back. What’s happened is the ratio of original starch to aromatic rings to oxidized rings has permanently changed and the ratio from when the tin is first opened will never be back.

That’s why aged is different from fresh, and why once a tin is opened many people notice a substantial change after only a week or two.

Hopefully I made at least a little sense. I’m sure my son could write a ten page paper to explain in more detail what I just tried to summarize.