can pu-erh cakes still be kept for aging after opened?

[LaybackPandas]

are they like wine or can it still be kept for aging after it has been opened?

[Trioxin]

Actually, for aging you'd want them opened.

[JAS-eTea Guy]

Your tea can be kept just fine for aging after it has been opened. You just need to keep it like you would any other time. Keep it away for strong odors such as kitchen smells. It will age a bit better in slightly higher humidity conditions than most people are comfortable but normal home conditions should be fine.

[LaybackPandas]

Actually, for aging you'd want them opened.

thats surprising! why?

[xuancheng]

Actually, for aging you'd want them opened.

thats surprising! why?

because you compared puer to wine, and under these circs.:

"open" means not sealed from air circulation .....

To age wine, it must not be exposed to air, but to age puer the opposite is true. Without wine in the equation, you could say 'open' or 'closed' is not so important for ageing puer because the packaging usually breathes a certain amount.

Suffice it to say, puer needs some fresh air, but not too much. You can keep it in a paper wrapper inside a carboard box and every week or month open it up to air it out a bit.

People will seal up their puer when they don't want it to age. Info on how to stop puer from ageing here: http://www.pu-erh.net/static.php?StaticID=12

[betta]

Actually, for aging you'd want them opened.

thats surprising! why?

Well, I would say wine is simply different from tea.
In the aging (fermentation) process, water and oxygen play a key role. One must control either or both of these elements to control the aging process.

Wine, doesn't matter red or white, contains at least water, alcohol, glucose, microorganism and wine acid.
If you open a bottle of wine and expose it to the oxygen in the air for some time, you'll get a solution mixture of alcohol and wine acid.
The bacteria converted glucose and all stuffs there to become wine acid only if they have enough oxygen. Therefore one must seal it, to let the fermentation takes place slowly and towards desired direction.
In brief, wine, by default has excessive water content, so one must control the aging (fermentation) process by limiting oxygen exposure.

Tea is different from wine in composition as well as the bacteria involved in its fermentation.
Here we have the possibility to control the water as well as oxygen. For easy storage, one control the water content (moisture) instead of oxygen.
Therefore the microbes can age the tea faster if there's enough moisture providing they can get unlimited amount of oxygen from the air.
Excessive moisture will ruin everything as well.
In brief, tea, by default doesn't have excessive amount of water, so one can control the aging simply by controlling its water content.

You can slow down but not completely stop the aging process by mitigating both water and oxygen.

[TIM]

betta - Do you think raw puerh really need that much air to age? A bottle of wine will have enough O2 to age for 50+ years. So a sealed bing/tong might be able to age itself like an uncorked bottle? Airing out good puerh is like decanting a nice bottle, what release to the air will not come back.... It might smell wonderful in an open storage with tangs of puerh, but I always think its a double sword.

Every time I walk down the storage in around this time of the year, it was like tea heaven. The aroma from the tea filled up the whole basement. Even most of the tongs are sealed. However this does make me concern. The more the tea release its favor, the less the tea will taste in the future. Just a thought.

[wyardley]

Layback - what do you mean by "opened"? The paper wrapper (or paper or bamboo tong wrapper) will still allow air to flow. Of course you can continue to age the tea after you have opened the wrapper, because the wrapper isn't airtight in the first place.

[Drax]

A paper wrapper or even most tong containers are not going to seal the tea against air. You'd need plastic or some other air-tight (hence the word) container.

I have a sneaky suspicion that "opened" here means "sampled" (i.e. taken a piece out of a bing/brick/etc). Although I have seen bings wrapped in plastic wrapped, so it could refer to that, too.

Regardless whether 'opened' means exposed to air or a piece has been sampled, you can continue to age the tea once it's been opened, keeping in mind the items already mentioned (humidity, air flow, temperature, etc).

[betta]

betta - Do you think raw puerh really need that much air to age? A bottle of wine will have enough O2 to age for 50+ years. So a sealed bing/tong might be able to age itself like an uncorked bottle? Airing out good puerh is like decanting a nice bottle, what release to the air will not come back.... It might smell wonderful in an open storage with tangs of puerh, but I always think its a double sword.

Every time I walk down the storage in around this time of the year, it was like tea heaven. The aroma from the tea filled up the whole basement. Even most of the tongs are sealed. However this does make me concern. The more the tea release its favor, the less the tea will taste in the future. Just a thought.

Tim, the fact that the wine turns to solution of wine acid in open air is a result of fermentation. It really does take O2 more than the amount available in the bottle.
However in case of wine, this fermentation (aging) has to be controlled not to end with complete wine acid formation, therefore the O2 given is very less. If I am not wrong, over-aging will lead to sour wine as well.

I've no exact data how much O2 will be needed to age puerh. It is also dependent on the specific microbes involved. I do work together with people who are working with fermentation for production of fine chemicals. In aerobic fermentation (which requires o2), the o2 intake is frequently the rate determining step in fermentation (aging) rate.
I believe tea aging is an aerobic fermentation and since O2 uptake is absolutely not the main issue in an open air, then humidity is the rate determining step.
Off course temperature is the most important factor at the end.

I understand your concern about loosing the aroma by airing, but the aging (fermentation) involves not only the matter of uptaking substances for microbes (O2, glucose, etc), it concerns also disposing substances out of the microbes.
If the substance responsible for good aroma is the product of microbes and we limit its disposal to the air by sealing it in a small jar, then fermentation rate will be lower than airing it in larger jar.
Once the medium is saturated with the fermentation (aging) product, the microbes can't 'eat' and thus age properly again.

It is a matter of "take and give". One can't hold new items on his hands without letting go those he holds now.

[TIM]

I see your point from a scientific angle, and I am not questioning your facts on your work with fermentation for production of fine chemicals. Since I am not a Scientist or Chemist, I have all the respect to professionals like you for these kind of data and inputs. What I can only contribute are my limited experience on aging wine, tea and cigar, which I think they all share the same aging path.

In the beginning, when I was first interest in finer wine, often I would uncork a good one without letting it "age", drinking it 5 years earlier before it even gets to their first maturity stage. I still remember opening up a Gaja Barbaresco 1997 in 2002, just because I am not patient enough and ended up "wasting" it. I have done the same thing with cigar many many times also.

But for puerh, I am lucky enough to learn from good collectors. My first taste of proper aged vintage puerh is a 50s red label back in 2001. The tea was "refined storage" since the early 80s, and that helps me understand the importance of what good puerh's potential is. It's the same as good wine and smoke, because we are talking about something which could be aged for over 100 years if properly stored.

For me, "give and take" is to enjoy older collector's dedication on their collections (puerh, wine and cigars) , and letting younger generation to take a bite out of mind in my later years. Hoping to continue/pass on the knowledge I've learnt from the tradition.

http://themandarinstea.blogspot.com/200 ... orage.html

[betta]

For me, "give and take" is to enjoy older collector's dedication on their collections (puerh, wine and cigars) , and letting younger generation to take a bite out of mind in my later years. Hoping to continue/pass on the knowledge I've learnt from the tradition.

http://themandarinstea.blogspot.com/200 ... orage.html

I consider the knowledge from tradition is invaluable collective wisdom being refined and perfected over years and generations. Science tries to explain and to predict, but it can't beat the best supercomputer, the human brain.

I'm well aware of my ignorance in the world of tea; therefore I'm here to learn from anybody who knows more. I'm grateful to find people like you who are generous to share and pass down your experiences and informations to others. Some are writing it systematically in a blog so that others don't have to get stumbled by the same stone our predecessors had. Some are ready to answer queries during their busiest time. Some are giving their reviews on any kind of subjects that others may/may not encounter in the future.

At the end my experience tell me to follow the traditional way while avoiding negative factors that science predicts.