28th January, 2010: Posted by glpease in Tobacco, Science

The following question is paraphrased from one that was asked on one of the forums today. I suspect it’s a fairly commonly asked question, and figured it had a place here in the Chronicles, along with my response.

Does it ruin the aging process to open a jar once in a while to sample? Should I only open the jar when I’m ready to smoke the entire contents?

Ruin it? No. Change it? Absolutely.

The biological and organic reactions that are taking place in the tin/jar alter the little sealed environment. Gasses are being consumed (especially O2) and generated (CO2) by biological processes, and further organic reactions are taking place more slowly, depending on what’s present in that environment. The instant that seal is broken, there’s a rapid exchange of air with the surrounding environment, and everything — everything — that was going on before is going to change. Different reactions will begin — not necessarily bad ones, just different.

It will never be the same again. It cannot be. If you take two jars, age them for a year, open one and re-seal it, then come back in another year, you’ll find two different tobaccos. The will probably not be dramatically different, but they’ll certainly be noticeably different, and if you extend those times - five years and five years, for instance, the divergence of the two samples will be much more dramatic.

To further confound things, the size of the container, the density of the packaging, the temperature cycles during storage, and other similar factors will also play a role. The tobacco that I store in my basement will likely end up quite different after some years from the same tobacco stored in someone’s desert home, or someone else’s northern Montana garage. And, the 2oz and 8oz tins will age somewhat differently because of their respective package densities. (Not dissimilar to the way a jeroboam of wine ages differently from a bottle.)

Once that tin/jar is opened, the effects of the sudden environmental change are irreversible. Aged tobaccos begin to change in different ways as soon as they’re exposed to the air. Much of the oxygen had been used up during the aerobic phase of the original aging process, and the microorganisms that thrived once have long since been deactivated. And, now that there’s fresh air available, oxidation and new life can again begin, but what that oxygen has to work with is quite different from when the tobacco was first sealed. Again, it’s probably not a bad thing; I have yet to experience tobacco that has been “ruined” over time, unless it’s been cooked by to much heat, or frozen, or otherwise abused.

One of the reasons I don’t like plastic bags for tobacco storage, or most plastic containers, for that matter, is that they are generally pretty good at keeping moisture in, but pretty poor at keeping some of the more interesting non-polar molecules, including oxygen, from walking through their walls. Glass is great. Tins are great. High-barrier, multi layer bags are great, but you won’t find those at WallyWorld. Freezer bags, Seal-a-Meal plastic, and so on, just aren’t up to the task. But, I’ve written about that before.

To further complicate matters — not every tin will have exactly the same balance of microflora and fauna when it’s produced. There are wild yeasts and bacteria that will be present at different levels in different batches, depending on when they’re produced, where the leaf came from, where it’s been, and a variety of other factors. All tobaccos will age, but the results, though usually relatively similar, are rarely identical. Does it really matter?

Probably not much. The good news is that even when things are different, they’re mostly still good. Though that jar of aging weeds that gets opened and closed will certainly be different from one that remains sealed, the chances are that, if the tobacco is great to start with, it’s going to continue to be great, and maybe even better.

And, that’s the short answer.

One more thing. I do keep some jars of the blends on hand I smoke most frequently. These are apothecary type jars with an excellent silicone rubber seal, so the tobacco’s moisture content remains quite stable over time. The contents of these jars definitely changes over time, and I often really like the results. A blend that is fairly young, stored in these jars with a fair amount of head space, dipped into daily, or weekly for a few months takes on some wonderful aromas that aren’t present in the same tobacco kept sealed for the same period of time. It’s not better or worse, just different. For me, it’s often reminiscent of the magical aromas in the jars at Drucquer’s when I first took up the pipe seriously.

I will never forget opening one my jars of Piccadilly that had been sitting for a while, and taking a deep whiff, only to find myself instantly transported back to 1980, or thereabouts, when I first lifted the lids and stuck my nose into the jars of Red Lion and Devil’s Own on the bar at Drucquer’s. Delightful memories!

-glp



