Vacuum Sealed Tobacco Tins

[jvnshr]

I have a colleague at work with whom I discuss interesting stuff all the time including physics, chemistry, biology, politics, etc. During our discussions we always find some unexpected questions and ask each other, well it's mostly him asking because he knows a lot more. Few days ago we were talking about tobacco and suddenly a question appeared. Are vacuum sealed tobacco tins perfectly or partially vacuumed from engineering point of view? If they are partially vacuumed how much air is left inside? I know that there are vacuum sealed tins and just sealed tins, I am talking about vacuum sealed tins here. He explained me that they couldn't be perfectly vacuumed because 1) It would prevent aerobic aging process (and here comes the most interesting part) 2) Water inside the tobacco will start boiling at lower temperatures. Does anyone have any idea about it?

 

[cosmicfolklore]

I actually am not sure how the tins are sealed. But, my understanding on canning in general is that different products get canned under different pressures, measured in pounds. When I can tomatoes it is under much less pressure in a "pressure cooker" than green beans, because of the acidity. Heat and steam are used to create the pressure.

Maybe tobacco tins are done similarly. But, I don't think that the tins could withstand an "absolute" vacuum.

 

[fitzy]

I vaguely remember seeing/hearing somewhere that vacuum sealed tins inhibit the aging due to the lack of oxygen. That the little bit that's left gets used up and then the aging slows. I also remember seeing that it said they see a bigger difference with those tobacco's taken out of the tin and put into mason jars.
The source of this may have been Brian on the podcast. Might want to reach out to him.

 

[nevadablue]

Of course if all the gasses were evacuated from the tin, it would be crushed down around the tobacco, and then probably leak. It is just a partial vacuum to create the seal. The sealing goo in the lid needs pressure to keep it sealed. The vacuum holds the lid tight. Very similar to canning jars, those just need to maintain the seal to stop air movement in and out.

 

[cortezattic]

In the PipesMagazine Mac Baren Factory Tour Part 3, at the 07:00 mark, Per Jensen states that their vacuum machine removes 40% of the air in the tin, ostensibly to keep the seal engaged, as nevadablue suggests.

Jensen was referring to the round, flat tins with twist-on lids.

 

[nevadablue]

Thanks for the link. It will be interesting to watch if it ever downloads. They should modernize their video format to match the factory. Oh, just in time manufacturing isn't for anything but saving money on inventory. That labeling BS is just that. You and I could come up with a label process... and storage process... and all the rest. Money only...
Nope, can't play it. Must convert, grrr. I do want to watch the videos. Sigh...

 

[cortezattic]

It's worth the hassle to convert the format. Realplayer worked for me.

My gripe is with the god-awful background music that Kevin selects. It's shrill, raucous, and completely out of character with the contemplative, serene atmosphere engendered by pipe smoking. The same goes for the podcasts' bumper soundtrack -- but that's all for a different thread.

 

[cosmicfolklore]

My gripe is with the god-awful background music that Kevin selects

I totally agree, bluegrass lends itself as the obviously contemplative music for pipesmoking. And, if not bluegrass, a great compromise would be anything with bongos. ::

 

[nevadablue]

I got it working. I run an iPad for everything and have an app that converts the FLV to MP4 for normal people to use. Does anyone use flash for anything? Grrr...
Yes, the video was quite interesting. The factory background noise and poor audio recording didn't help. I had the volume all the way up and both hands cupped over my old ears, but I got to hear the words anyway. LOL, old grouch I am.
Now to download and convert the other two videos...

 

[cortezattic]

Bluegrass or bongos?! I had in mind something more like a Beethoven string quintet! :rofl:

 

[jpmcwjr]

Perfect vacuum? No; you couldn't get the tin open without destroying it. Or, as pointed out above, atmospheric pressure would do it in.
And I wonder if there is a study regarding aging and oxygen. Er, one that's an actual study.....

 

[nevadablue]

As I age, I find I need more oxygen, no study necessary. 8)
:rofl:

 

[nevadablue]

I must have lost my reply earlier. I did get the videos converted. I run an iPad almost all the time. There is an app that converts the FLV crap to mp4 for normal people. Does anyone use flash anything anymore? Also, the noise of the factory makes the dialog almost useless. I did succeed in hearing it though. I did enjoy the video, now to download and convert the others.

 

[nevadablue]

I saved this picture from the interviews. I think I will clip the middle out of the pic and make wall paper for my office from it. :twisted:

 

[mawnansmiff]

As mentioned above, a perfect vacuum would crumple the tin flat. That said, I've often wondered how they do pack tobacco tins with a partial vacuum.
Regards,
Jay.

 

[cortezattic]

Jay, the video link above will give you some idea, though the process wasn't explicitly described. It looks like the tins in the assembly line enter a partially evacuated chamber, at which point the lids are screwed on. So, they emerge from the chamber with a lower internal pressure.

 

[jvnshr]

Thanks for your answers, everyone.

Heat and steam are used to create the pressure.

You are totally right Michael, however I don't think that they play with the heat while dealing with the tobacco, I mean while packaging.

Of course if all the gasses were evacuated from the tin, it would be crushed down around the tobacco, and then probably leak. It is just a partial vacuum to create the seal.

Totally agree with you nevadablue.

In the PipesMagazine Mac Baren Factory Tour Part 3, at the 07:00 mark, Per Jensen states that their vacuum machine removes 40% of the air in the tin, ostensibly to keep the seal engaged, as nevadablue suggests.

Cortez, that is the answer I was looking for. Thanks a lot, sir.

And I wonder if there is a study regarding aging and oxygen. Er, one that's an actual study.....

jpmcwjr, someone shared this article on another thread. Read the comment of Kashmir, it is really interesting.

As I age, I find I need more oxygen, no study necessary. 8)

:rofl:

 

[mso489]

I only earned a "C" in high school physics though I enjoyed it greatly. I had a crush on my smart-ass lab partner, though she didn't reciprocate -- too fun smacking me down. But I'd say something has to go "psssst" when you open the tin, and I suspect some of that gas is that composite we call air. So it's not perfect vacuum.

 

[ryeguy]

I vaguely remember seeing/hearing somewhere that vacuum sealed tins inhibit the aging due to the lack of oxygen. That the little bit that's left gets used up and then the aging slows.

I seem to remember Pease saying (not in the above linked article), or at least implying, that the reaction that causes aging in tobacco is anaerobic; thus, opening the tin stops aging. If you reseal it, the aging clock resets so to speak.
I could be wrong. For that matter, as far as I know, he (or whoever I read) could be too.