MarshalN wrote:You have to remember that most places are not like Malaysia, and the storage conditions in drier, cooler places are not going to be the same. Slowing down aging via wrapping maybe a good idea in Malaysia, but my friends in Hong Kong, some of whose livelihood depends on them storing their tea well because they sell tea for a living, don't wrap their teas until they reach about 30 years old. Experiments have been run and optimal storage has been discovered a long time ago - it's not news. They've been in the business for three generations. Storing tea in places with real winters will mean even slower aging to start off with, which means that methods to make it even slower, like wrapping, is probably not going to be suitable. If someone in Chicago read this and went ahead and wrapped all his tea in shrink wrap, 30 years later he'll still have "grape juice", as shah put it. In Malaysia it might've turned into wine, but in other places it'll not be so good.
So I think a very important thing to remember is all the "shrink wrap" advocates here are talking of storage comparisons with hot and humid places like Malaysia and Singapore. YMMV if you're in a colder and drier climate.
i'm definitely not forcing people to think that sealed storage is the mainstream way to go, but to have it recognized as a possible alternative than the current condescending views to it.
actually grape juice is made into wine by controlling the oxidation, if you make it anaerobic, the juice becomes wine. if its aerobic, the juice becomes vinegar. controlled oxidation is the key
sealing is a way of controlling oxidation. many teas fear exposure, if you leave your dragonwell, spring gaoshan oolong etc exposed over time, it wont do any good to the tea. once it goes stale, your only option is to keep it for long enough, in an environment good enough for it to develop the "aged" taste (thats if the material is right, dragon well is too poorly lignified to be able to aged that way).
whilst some would argue that pu-erh tea is compressed to save space, and that it is used as a currency, make it easy to transport, the tea bricks/cakes they made in ancient days when tea was currency, is probably not the type of pu-erh we have today.
what i see pu-erh tea's compression, is an attempt to control the oxidation over time. if maximum exposure, free exposure, airy, constant high humidity is the key to aged pu-erh's good taste, then why not loosen out all the cakes in storage into loose leaf to have maximum contact and benefit from this? in reality if you have loose leaf, the tea advances faster than the cake form. in 2003, i bought a menghai gushu cake, due to poor compression, it was already falling apart at the sides from the start. i removed the loose leaves (about half the cake worth) and put them into a canister, sealed, and the remaining compacted parts, went into a ziploc. in a recent tasting, the loose leafs advanced way faster than the compressed parts. i had given some of the loose leaves as samples to other tea chatters as an example of what could come out from such a storage method.
once compressed into a cake, the only way bulk of the leaf in the middle of the cake or brick to get exposure to oxygen, humidity, is through the surface leaves of the brick or cake. it becomes a "gradient". if you do a direct cross section of a tiebing i.e. XG8663, or if you brew the middle of the tiebing and the surface, the color is different, the wet leaf is different color too.. but all same cake. due to over-compression, it becomes "anaerobic" in the middle, and less affected by humidity.
apart from the gradient, the other issue that is critical is water/moisture content. i've done water content measurements on cakes that are newly produced to that of cakes that taste good, cakes that taste bad. so if you seal a cake, you had better know the water content of it before you do so, if not it will be overly slow, or eventually mouldy.
a dry, low compression cake was aired for a month, and when the surface and inner leaves are measured, there was almost the same water content, difference of only about 1%. but for a more heavily compressed cake, the difference between surface and core is larger, at several percent.
do not get mistaken that i'm obsessing over water here, just that i use it as an indicator of how much "air penetration" is going on into the cake, since the air brings moisture in, it would bring oxygen in too. i'm not equipped to do oxygen/gaseous studies at the moment, but if a way can be devised, it would be more revealing.