; Cwyn's Death By Tea: Airing, Storing and Wrapping Musty Old Puerh Tea ;

Saturday, September 3, 2016

Airing, Storing and Wrapping Musty Old Puerh Tea

Saveur Blog Awards Ceremony

Just an update on the award nomination this blog received from Saveur Magazine. I had hoped to attend the awards event in NYC September 26-28, but at this time I don’t think I will be able to get the money together in time. While I can pull together a few hundred in a month’s notice, the funds for a NYC trip are just beyond what I can scrounge up in a few short weeks. While this is disappointing, I’m mostly resigned to the idea that I probably won’t be able to attend. A friend encouraged me to try GoFundMe, so I did set up a fund. The link is above at the top right hand of the blog, and here. If I can meet the fund goal remaining of $1350, I will be able to go. If not, I will return all donations.

Stack of once-moldy teas and a soft, but stiff craft brush.

Airing and Storing Musty Old Puerh Tea

Over the past year I’ve worked on airing some particularly wet stored puerh teas. I received these teas from friends who had declared them a loss, and planned to toss them out. When I suggested trying to air them myself, my friends graciously mailed them to me with a “good riddance” or some such. So, exactly when should we air out our puerh teas?

*When the package arrives off the boat from China, or elsewhere.

I’ve noticed that nearly all my puerh teas arrive in need of airing, some more than others. Shou puerh definitely needs a good airing and settling time. Most teas are stored in warehouse storage by vendors, often in huge stacks. Some warehouses have a climate control system, but others might not. The best stored teas are usually from collectors who take premium care of their tea, but most of us are buying tea from vendors who use some type of warehouse storage. Regardless if the tea is dry or wet stored, most teas benefit from airing upon arrival.

*When the tea undergoes a wet storage process.

Many puerh vendors offer teas with a “wet” storage process. Many people enjoy the flavor of a wet-stored puerh tea. I like the excellent start to aging a puerh tong that a few years of more humid storage yields. In my drier climate, I can air and finish off the aging myself, and this results in the tea moving through those awkward “teenage” years of fermentation more quickly. As an older person, I can’t expect to live long enough to age out many of my teas. I’m okay with that, but I do want some drinkable teas and a bit of wet storage is just the ticket.

Musty Taobao cake sample, acquired from a friend
However, some puerh teas are fermented in a fast “wet storage” process which is meant to mimic the twenty to thirty years normally needed to fully age a sheng puerh tea. These cakes then are sold as fake imitations of famous brands and recipes. Some wet stored teas are well done, and turn into nice daily drinkers. Others are more of a mess. I think just about anyone getting into puerh tea will get a musty cake at some point in their buying history.

"Start photo," September 2015.
The moldy teas in this project consist of a set of four cakes originated from a Taobao vendor and arrived literally covered with white frosty mold. This is a type of mold which can be aired out over time. I also received another sample of a 1/4 beengcha which similarly resembled a powdered doughnut, and the friend who sent this to me felt afraid to even try the tea. I used my vintage crock bread bowl as storage for airing these teas over the course of about eleven months. Now that I’m approaching a year with these teas, it’s time to assess their condition.

"Start photo," September 2015
When the intact beencha teas arrived, they had wrappers which smelled musty and had bug bites. Even in the dry weather, the musty smell clung to the wrappers. Washing them was unsuccessful, as the paper used to wrap the tea was not a high quality fiber paper, but just a tissue paper quality which disintegrates in water. 

Washing the wrapper--a fail. 
Given the poor condition of the wrappers, I decided to toss them and start fresh with new wrappers. So, I aired the tea in the bread bowl without any wrapper. If you want to save your wrapper, try exposing it to sunlight for a few days and definitely keep it apart from the tea for a year or two.

Over the winter, I aired the tea in the bread bowl, alternating a day or two exposed and then covered the bowl on dry days. My house is exceptionally dry in the winter with around 10-30% RH, which is desert climate. This is enough to send most molds to the grave. Occasionally I wiped the wood lid with water to keep at least some moisture in the tea. This is a balance of humidity and dryness to keep the tea alive but not enough to allow the mold to proliferate.

Montage of "start" photos, Sept. 2015.
As the mold died off, I used a soft but stiff craft brush to remove the frost from the exterior. I know that the interior of these teas likely contains spores as well. In fact, breaking up the tea is the best idea for airing and storage. But I’m certain my friends prefer intact cakes. Airing through the cake entirely to integrate the wetness will take another several years.

My goal was to encourage the correct fermentation and discourage mold without killing off the tea. In other words, I want to get the tea back on the right path of fermentation. The teas are still a bit green, and this green needs to live in the meantime and ferment more, but without the nasty white mold taking over. The tea lost most discernible odors over the dry winter months. In the late spring of this year with the start of the hot summer season, I moved the bowl to my three season porch along with my other teas to take advantage of the humid time of year.

In bright sun for a photo, summer 2016
This summer we’ve had an unusually muggy and rainy summer, many days with tropical pouring rains and heat. Alas, the local farmers are reporting “sudden death syndrome” in soybean fields. The disease is due to a fungus located in the soil which attacks the roots of the soybean plant and kills the plant in late summer. Even worse, if this fungus shows up on a large scale, the entire field of soil is ruined for soybeans. Crop rotation does not remove the fungus from the soil, and currently no treatment exists except to plant other crops which are not susceptible. So, you know how humid our summer is when farmers report “sudden death syndrome” in the fields. That’s bad for soybeans, but good for my teas.

September 2016
Our humid summer added moisture back into these teas. I observed very faint frost come and go from the cakes early on. At the start of the summer in mid-May, on very muggy days, the tea returned to a grayish look. This tendency stopped over the following months, however. Well into August I didn’t notice any differences in appearance on muggy days or drier days. We had many days where my porch got well over 20C during the day, and even over 80% RH at night after rains and fog. On days like that I kept the cover off the bowl and I keep a large ceiling fan running all summer long. When frontal systems passed through my area, we received much drier and cooler days with humidity lower than 60%. The combination of drying over the winter and then a moderate humidity added back, on and off again, re-started the fermentation. I believe the difference in developing mold versus not is the air circulation and also the spells of dry and cool days and nights.

Another sunlight photo.
Today I removed the teas and gave them a good brushing outside to remove any dusts or particles from the exterior. I don’t notice any particular smell now to these cakes. It’s time to re-wrap the tea.

Finished stack of tea.

Wrapping Puerh Beengcha

I’m not an expert wrapper. Despite what Old Cwyn thinks of herself, she won’t be hired by the puerh industry any time soon. But I can re-wrap a cake well enough for storage. I like the mulberry papers sold by Wymm Tea. Unfortunately the price has increased from the 50 cents per sheet I paid to now $1 per sheet. But the papers arrive nicely rolled up in a slim box which is great for storing them until needed.

Start by placing the cake upside down.
A good wrapper like this, when pulled to the center of the cake will naturally form a crease. It’s not necessary to make perfect creases. Also, the quality of the wrapper is more like a “rag” texture, which means I can re-wrap these teas many times again and the wrapper will hold up without tearing, and allows one to “ball up” the ends to secure it as the cake is consumed.

Starting creases.
The trick to wrapping is to pull the wrapper toward the beenghole and work with the creases that form, adjusting to the size needed. I'm doing a right-handed fold. A left handed fold faces the opposite direction.

Pull the wrapper toward the beenghole.
Firmly crease the fold with your thumb once you get it where you want it. You might notice that the first few folds will take in the corners and form a a sort of straight line across the cake. Someone folding more perfectly might have better geometric lines.

Folds spaced about one inch or 2 cm
My reward for this project is scooping up loose tea from the bottom of the crock bowl. I have enough loose tea for a gaiwan. This tea is lively on the tongue, so it’s definitely not dead. I give the tea three rinses and drink around six cups or so. I see a few green leaves in the mix, which means a bit more flavor left to develop. All this age in the tea makes for a warming brew, and although the brew resembles shou, the tea is definitely sheng.

The musty flavor needs a couple more years to integrate into the tea, but I’m certain the white mold won’t return under ordinary dry storage conditions. By that I mean a proper room temperature with a moderate relative humidity. 

Wrapping a partial beeng holds best with a twist of the ends.
Once integrated, the musty odor will turn to more of a mineral or graphite taste in the tea. Using a clay teapot will take the musty edge off the tea in the meantime.

Secure the cakes with ordinary string.
Storing the stack of cakes in a crock is sufficient. Any excess of humidity in the surrounding air will absorb into the paper wrapper before it gets to the tea. I don’t have a problem storing this with other sheng cakes because the wrapper is rather thick, but not everyone stores wet and dry teas together.

Loose tea from the bottom of the crock. This stuff is a bit white still.
I hope everyone remembers to air out new teas as they arrive from China. Give them a chance to develop over six months before making a final opinion. A tea you hate on arrival may taste very different to you down the road. And don’t throw away those musty old teas or Taobao mistakes. You can always find someone online willing to take tea off your hands if you still hate the tea after giving it a chance to develop. While most people don’t want to do the fuss of proper airing and storage, I encourage anyone to spend relaxation time like this with your teas.

Steep after three rinses.

Have a great Labor Day weekend!


  1. Interesting! How is it possible to tell what is ok for mold or what's going to be dangerous to keep around?

    1. Yellow or green molds are not good. By yellow, I distinguish from the beneficial fungi Eurotium cristatum, "golden flowers, which grow on Fu Zhuan brick tea and are a delicacy. Puer should not, in general, have mold when the cake is Yunnan Assamica varietal.

  2. Hi Cwyn,

    Do you think the same process could kick-start dried out cakes? Or, would you handle those differently?

    1. If the cake hasn't been dried out for long, I think crock storage is a good way to concentrate moisture when the inside of the lid is wiped with a damp cloth, or soaked clay pieces or pouch buttons added. Because this tea was already suffering mold, obviously I didn't add moisture very often for some months.

  3. What would you recommend for ripe pu-erh cakes with an extremely strong mushroom/musty smell? I have a few cakes that I got and right from the start, the look and feel were off. They felt too dry and pieces came off in my hands. The flavor of the brew was like drinking death. I'm happy if I can save them and the later brews did give me some hope that there might be a good flavor hiding in there, I just don't know how to save them. The area where I live is so humid that the few cakes I tried leaving open to the air got moldy. Is a crock a good place to store them on a regular basis? Should I invest in one? Right now, the only way I've been able to keep pu-erh in my climate is to seal them in air-tight containers and occasionally open them to add some new air. This works but I'm concerned with how dry these are. I feel like they need more moisture.

    I also have a raw pu-erh that got moldy being left out to the air. I took the moldy pieces off and then inspected the cake with a jeweler's loupe. It looked mold-free, but just to be sure that it wasn't inside the cake, I broke up the cake so that it's loose tea now. The scent was green and fresh so I was encouraged, the moldy pieces did not smell so good. I inspected it with the loupe and it seemed to be without mold. I then left the tea to air out, outside in the afternoon when the humidity was reasonable and the sun wasn't too bright. I could get a separate stoneware container for the raw pu-erh and put it in and then moisten it lightly, periodically. Should I put it in with another raw? I have a raw cake that wasn't moldy that I could put in with it, but would that be safe?

    I'm new at trying to fix bad situations with the pu-erh but I'm very happy to learn, so if you have any suggestions at all, I'd greatly appreciate them.

    1. Sounds like you have a very humid climate. Air circulation and flow is key for humid climates, keep that air moving. I would look for unglazed puerh jars and break up your ripe or moldy tea and leave the lid off, making sure you have a fan on or some sort of air circulation.

      For fully aged teas or on very humid months you might want to consider shrink wrapping individual valuable cakes to keep out the humidity. People from Southeast Asia report needing to do this during rainy seasons.

      I think we learn a lot from mold, about the needs of the tea. I'm glad you are learning as I have from my storage issues.

    2. Thank you so much for your guidance! I got an unglazed pot today. I stacked the pu-erh in it (it's too narrow to lay them out like what you did), and I'll rotate them periodically. I put the cover on since it's 93% humidity here now and that's just way too much. I think I'll take the pot outside with me and set it in the shade and take the cover off while I'm gardening so it can get some fresh air. The cakes were really dry when I got them and they need moisture, but in moderation.

      Right now, they're in paper wrappers. I taped the ones shut that I'd opened. I'm going to look into getting some mulberry paper and natural string to secure them.

      Thank you again for all your help. I was really so disappointed getting such rank cakes and it's great to feel like I can do something to try to fix them, rather than being stuck with such bad tea. So, I appreciate that. :)

  4. What do you recommend for dank cork tainted wine tasting wet Taiwan stored cakes? I unwrapped them and stashed them in a closet in my guitar room and set the room humidifier at 60%

    1. I would store them out in the open air wrapped In paper. Depending on the level of dank, at least 6 months. The above teas took a couple of years to improve.