[wileyone]

 I recently learned that cigarette companies use a percentage of expanded tobacco in their products. The basic process, as I understand it, is to force CO2 into the tobacco until it forms dry ice and then rapidly heat it which expands the plant material as much as two fold. This clever bit of technology has been used since as early as the late fifties/early sixties. The main benefit of course is increased volume. Some residual benefits include decreased nicotine, tar and so on. This fascinates me and I would like to reproduce the process on a small scale in my home if possible.
 Will a sample of tobacco absorb enough CO2 from a block of dry ice if placed into an insulated cooler together? If that sample is then popped into an oven will it likely expand noticeably? Are there any dangers involved on a small scale? I assume a minuscule release of CO2 from the dry ice in the cooler and a tad more when heated. My basic hunch is that the dry ice needs to form in the plant tissue by way of pressurized CO2, my home experiment is basically the reverse.
 This is a really cool forum. Thanks for letting me post
 

[Arkcon]

Probably, this is done by using CO2 gas and putting it under pressure so that it becomes dry ice while intimately mixed with the tobacco.  Then once the pressure is released, the dry ice becomes CO2 gas rapidly, without needing an oven.  I doubt you can replicate it by just leaving them close to each other.

[wileyone]

Here's a link: http://www.aircodiet.com/images/25413_-_AIR_brochure_297x210_3fl_jet_korr03.pdf
The brochure describes the process in simple terms but it does specify heat to aid in the expansion.
The best I could do is pressurize the CO2 gas subliming from a block of dry ice and even then it would require a pressure vessel which I am unwilling to procure for what is nothing more than simple amusement on my part.
 I used to have a go to guy for my science questions but he passed away a few years back. He was incredibly intelligent, friendly as heck and could explain things so even I could understand them. He was well loved by all who met him.
Thank you for taking the time to respond Arkcon.

[kevinkevin]

Just to throw this out there, I saw a video a long time ago in which a chemist was describing the way to see all three physical states of carbon dioxide and I think what he did could be used to yield possible good results.  I all ways do experiments at home too and I try to find ways around the equipment I don't have.  If the pressure only needs to be present for a short period of time you could put a piece of dry ice and some tobacco in a plastic pipette and place it in a somewhat covered cup or paper towel.  When the pressure gets high enough the pipette will rupture and the tobacco should be carbon dioxide rich.  but the reason this might be a good method is because in the demonstration he did, before the pipette ruptured the carbon dioxide turned into a liquid, so for a couple of moments the tobacco will soak in liquid carbon dioxide.  That should most likely provide the leafs with a good amount of carbon dioxide.  Then when the pipette breaks the liquid will turn right back into a gas and the tobacco leaves should be left carbon dioxide rich.  In less it is just me, liquid carbon dioxide should be very effective, at least for a home experiment I believe.