We're all aware of the "cab vs dressed box" debate insofar as which is better for longer term aging. The purpose of this post is not to rekindle this debate. Rather, I would like to propose an explanation as to why one should expect identical cigars stored in these two different containers to age differently. Specifically, why cabs are better for the long term. For the remainder of this post, I'll use the term "cab" to mean any cigar container, including slide lib box, that is composed of cedar or cedar plywood only with no significant paper covering or dressing. I will also use the term "box" to mean dressed box or any wooden container with surfaces that are substantially or totally covered in paper.
First, let me restate the orthodox understanding of why cabs are commonly believed to provide superior aging performance: solid wood walls reduce oxygen access to the cigars thus retarding aerobic chemical reactions involved in "aging" and that this lowered reaction rate results in a more favorable balance of reaction products and byproducts.
Basically, this supposition hinges on the fact that the wooden walls and seams of the cab provide a significantly greater barrier to air entry (and the water vapor and oxygen contained in air) than the corresponding features of a box. This transpiration will occur primarily by permeation diffusion through the wood walls as well as around the space surrounding the seams. It's important to note that even if you have a fan circulating air in your humidor, the seams are small enough so that the primary mass transfer route into the cab will be by diffusion and not through convection aided by air currents.
My assertion is that this orthodox belief is incorrect, or at the very least identifies a far less significant mechanism that one might believe.
Part one of my argument is this. There is no significant difference between air or oxygen permeation between the walls of a cab and the walls of a dressed box. I make this claim based on three linked pieces of information. First, the walls of a box are wood or plywood just as a in cabs. Second, the walls are of the same approximate thickness as in cabs. Third, the decorative paper on the faces of the box walls is light basis-weight plain or clay-coated packaging paper and not a high-barrier variety such as wax impregnated or polymer coated.
What the above three points suggest to me is that based on materials considerations, there is no evidence to support the supposition that the walls of a cab and the walls of a box provide significantly different barriers to diffusion transport of air, oxygen or moisture vapor.
While one might argue that the seams of a cab and a box are different, I would respond that they may well be in certain parts of certain cab-box comparisons but that this is also not believed to be significant.
The second part of my argument has to do with the suspected reason for differences in aging performance. The paper dress is the culprit. I make this claim based on my experience in the paper industry. Paper is not just chopped up and pressed wood fibers. Most general purpose paper, including industrial and product packaging, is acid process. Furthermore, in addition to the wood fibers, paper is filled with surfactants, starches (sizing agents), bleaching agents, latexes and other binders, minerals (for whiteness and cutting properties), brighteners, dyes and pigments. And then there are also all the inks used in printing. In other words, it is a reactive chemical mush. But the paper itself is not the only factor. Since it must be affixed to the wood in some way, one must also consider the adhesive used to glue the dressing to the wood. Is it starch based? Animal hide (unlikely)? PVA? Acrylic? Thermosetting or water soluble? Taking the paper/glue composite as a whole, it should become clear that the paper dressing is very likely a source of chemicals, reactants and reactions that could well be antagonistic to the natural maturation of pure tobacco.
But the real clincher is this. If you could somehow magically and completely remove the dressing and adhesive from a box, what remains is...you guessed it, a cab. A clear example of this comes from a consideration of the Partagas Serie D No.4 cab and the Ramon Allones Specially Selected box.
Well, what about foil-wrapped or glass jars? These are special types of packaging that do not have the potential contamination issues of paper and they do provide a significant reduction to diffusion permeation as compared to any wood packaging.
So, in the end, based on a consideration of the materials aspects of cabs and boxes, it makes sense to me that cigars stored in cabs would age better, if not more slowly and in an analogous fashion to cigars stored in dressed boxes.
What do you think?
Wilkey
First, let me restate the orthodox understanding of why cabs are commonly believed to provide superior aging performance: solid wood walls reduce oxygen access to the cigars thus retarding aerobic chemical reactions involved in "aging" and that this lowered reaction rate results in a more favorable balance of reaction products and byproducts.
Basically, this supposition hinges on the fact that the wooden walls and seams of the cab provide a significantly greater barrier to air entry (and the water vapor and oxygen contained in air) than the corresponding features of a box. This transpiration will occur primarily by permeation diffusion through the wood walls as well as around the space surrounding the seams. It's important to note that even if you have a fan circulating air in your humidor, the seams are small enough so that the primary mass transfer route into the cab will be by diffusion and not through convection aided by air currents.
My assertion is that this orthodox belief is incorrect, or at the very least identifies a far less significant mechanism that one might believe.
Part one of my argument is this. There is no significant difference between air or oxygen permeation between the walls of a cab and the walls of a dressed box. I make this claim based on three linked pieces of information. First, the walls of a box are wood or plywood just as a in cabs. Second, the walls are of the same approximate thickness as in cabs. Third, the decorative paper on the faces of the box walls is light basis-weight plain or clay-coated packaging paper and not a high-barrier variety such as wax impregnated or polymer coated.
What the above three points suggest to me is that based on materials considerations, there is no evidence to support the supposition that the walls of a cab and the walls of a box provide significantly different barriers to diffusion transport of air, oxygen or moisture vapor.
While one might argue that the seams of a cab and a box are different, I would respond that they may well be in certain parts of certain cab-box comparisons but that this is also not believed to be significant.
The second part of my argument has to do with the suspected reason for differences in aging performance. The paper dress is the culprit. I make this claim based on my experience in the paper industry. Paper is not just chopped up and pressed wood fibers. Most general purpose paper, including industrial and product packaging, is acid process. Furthermore, in addition to the wood fibers, paper is filled with surfactants, starches (sizing agents), bleaching agents, latexes and other binders, minerals (for whiteness and cutting properties), brighteners, dyes and pigments. And then there are also all the inks used in printing. In other words, it is a reactive chemical mush. But the paper itself is not the only factor. Since it must be affixed to the wood in some way, one must also consider the adhesive used to glue the dressing to the wood. Is it starch based? Animal hide (unlikely)? PVA? Acrylic? Thermosetting or water soluble? Taking the paper/glue composite as a whole, it should become clear that the paper dressing is very likely a source of chemicals, reactants and reactions that could well be antagonistic to the natural maturation of pure tobacco.
But the real clincher is this. If you could somehow magically and completely remove the dressing and adhesive from a box, what remains is...you guessed it, a cab. A clear example of this comes from a consideration of the Partagas Serie D No.4 cab and the Ramon Allones Specially Selected box.
Well, what about foil-wrapped or glass jars? These are special types of packaging that do not have the potential contamination issues of paper and they do provide a significant reduction to diffusion permeation as compared to any wood packaging.
So, in the end, based on a consideration of the materials aspects of cabs and boxes, it makes sense to me that cigars stored in cabs would age better, if not more slowly and in an analogous fashion to cigars stored in dressed boxes.
What do you think?
Wilkey