; Cwyn's Death By Tea: Puerh Storage is a Crock ;

Tuesday, October 7, 2014

Puerh Storage is a Crock

Recently I read an old comment in a tea forum discussion along the lines of "because I live in North America, I'm not in a position to talk about storage." We've got to stop that mentality. For one, we have to store our teas. And two, in an age of refrigeration, we are forgetting that less than a century ago people  here were in the business of storing and fermenting food and beverage items at home. Had they not, we wouldn't be here. Therefore, a more accurate statement would be "20 years ago we didn't have Puerh Shopping over the Internet." But we most certainly had storage and fermentation, as anyone from a farm family can tell you. My puerh storage has more in common with midwestern cabbage than all the tea in China. I will invite people to participate in a North American Storage Experiment using samples we all have lying around.

My storage is based entirely upon my local climate. What people do in China to age puerh is of little to no use to me in Wisconsin, this is my starting point. The climate I'm living in has been compared to Siberia, a climate of extremes, hot in the summer and ghastly cold and snowy in the winter. In summertime, we're baking in humidity and hot sun, which is great for my tea cakes. Next month I expect the temps to fall below -20 C, requiring heat in my house which will take the humidity levels to 38% or lower. At best, home humidifiers might get me to 42%. Nothing remotely like southern Asia.

In China, Malaysia and other very humid southeast Asian countries, controlling mold and humidity naturally leads to using porous clay jars, baskets, and cardboard boxes. Or even blocking humidity altogether with vacuum sealing.  When I started aging shou puerh cakes in 2009, I dutifully followed Cloud's advice about storage in cardboard boxes. Fast forward four more years, I had shou that smelled and tasted like cardboard box. So not only did I have cakes that needed a rehab solution, also I starting buying really good tea that I need to preserve. Topics about storage on the internet tend to either focus on Asia or climates measurably more temperate and humid than mine. One common solution for many tea drinkers is a non-working refrigerator.

Some of my cakes are stored in a non-working dorm fridge from the 1970s, a small square thing that in no way resembles the dorm fridges of today which are much larger. This thing maintains 69-74 F/23C and 61% humidity without any added humidity. With a glass of water I can get around 63%, and adding a soaked clay shard I can get 64-66%. Okay, though somewhat dry and cool. I'm also concerned that the 40 year old dorm fridge has plastics in it that I know nothing about. Do you store your tea in plastic containers from the 1970s? Didn't think so. So I've spent the past 6 months experimenting with local crock storage, and based in my early results I plan to move all my cakes to vintage American stoneware crocks.
It's ugly, but unplugged it works.
One of the traditional means of storing small amounts of food in the Midwest has been the Crock. Glazed pots and crocks create a microclimate that resists  changes on the outside, maintaining an internal consistency. We have an abundance of brown glazed Crocks which are used to store fresh butter, cheese, pickled fish, sauerkraut, fruit preserves, honey and syrups of all kinds.  Even today we can still buy good old Wisconsin aged cheeses in little brown crocks, and empty ones are easily acquired in local secondhand (charity) shops.

My childhood memories include tripping over waist high salt glaze Crocks filled with green molding sauerkraut. Farming relatives collected a variety of ceramics, but I have no idea what happened to all the family sauerkraut crocks. A few years back I starting buying chipped crocks and urns at secondhand stores during a hobby period when I taught myself how to repair chipped pottery. I worked on lots of different ceramics before moving on to my target goal of repairing mid-century modern Scandinavian ceramics (particularly Rorstrand workshop pieces from Sweden). I sold all my fine pieces that I repaired, but I still have a lot of crocks sitting around that I worked on to learn to repair chips.

Crocks create a microclimate that is slower to react to changes in weather. The lids are loose enough to allow a bit of air in and out. To add humidity, I use a clay pouch button. A pouch button is normally used for keeping loose tobacco or weed at the proper humidity. It consists of a clay disc inside a metal case, you soak the button in water for a half hour or more until the clay inside is soaked, wipe it off and add it to your stash. The humidity lasts around 4-5 days.
This pouch button has some history, but I'll never tell.
I also use clay shards from red terra cotta flower pots. Talk about cheap. I just break them up with a hammer, clean and boil the shards and soak them in water. These last about 3-4 days because they don't have the metal case of a pouch button. In the case of a tea that has had traditional style wet storage already, then I will use a paper towel or napkin secured with a rubber band to allow more circulation than a lid. The paper also tells me that the tea is a humid storage tea in case I forget.
Clay shards, humidity on the cheap.
One thing I have found is that the humidity in crock storage and fridge storage does not penetrate bamboo tong wrappers or heavy paper wrappers very well. It's a wrenching decision whether to remove these even though I know I should based on the drier quality of compressed tuos especially.

This past summer, I started using unwrapped puerh samples acquired from my purchases to see what ceramics create the best change. Here are some photos of things I've got going. All of these will create a micro climate for either fermentation or preservation.

McCoy 1848-1990

McCoy pottery is a long standing US company and had many changes in ownership. The company mainly produced stoneware intended for sanitary food storage prior to widespread refrigeration. So incredibly practical were their pots that McCoy did not even stamp mark their pieces prior to 1930 or so. I use Brush McCoy and later McCoy pieces, which are differentiated by their glazes.
Brush McCoy pots. 2009 CNNP 7572 and circa 2000 "Ding Xing Hao"
Brush McCoy (circa 1910-1926) pots are recognizable with their heavy gloppy glaze, and often glaze "skips"-- places that are unglazed because the factory missed a few spots.  I've had good results airing out shou puerh and Hong Kong "wet" stored aged cakes in Brush McCoy. Again, the glaze keeps something of a microclimate in the pot to keep the tea from drying out too quickly. I keep a clean paper towel secured with a rubber band over the top to prevent dust from getting on the tea. The 2009 CNNP 7572 was kept in a cardboard box for 4 years and smelled like the box, and got too dried out. Sorry Cloud, but the Box doesn't work here in Wisconsin. After several months in a Brush McCoy pot, the cardboard smell is gone and the tea now smells sweet like a shou.
L, unmarked probably early Red Wing, R Brush McCoy
Both of these pots contain dzpuer's 2013 1 kilo shou brick, refer to my post "The New Soft Shou." The Brush McCoy covered with a paper towel is getting more air circulation because I intend to drink the contents first. The "Red Wing" covered brown crock is thick and heavy, maintains a cool temperature and is designed for long-term storage.

I also have a mid-century McCoy soup tureen which is a perfect size for this tong of 2014 Ban Payasi cakes.
Mid-century McCoy piece in my last post about 2014 Ban Payasi
Red Wing, Minnesota

The quintessential sauerkraut and fresh water stoneware pottery, Red Wing is a bit more collectible than McCoy because pieces are geared for specific types of storage, such as whisky jugs, water coolers and of course their fermentation  crock. Some of the more unique pieces can be pricey, but the market has honestly declined for collector value. People who buy Red Wing stoneware nowadays intend to use the pieces for food or beverage storage rather than just displaying them. Salt glaze crocks are popular here with "survivalist" people who think that Obama is going to usher in the end of days. The pottery is thick to really create a sterile microclimate and be practically bomb proof.
Red Wing, Minnesota canister
My Crock here is probably a flour canister, and rather sentimentally holding a number of Mandala Tea (Rochester, Minnesota) puerh cakes. A pouch button provides additional moisture. I got this piece for under $20 because of a 3 mm  clay split in the lid, a tiny factory flaw. I've given away a couple of Mandala cakes but haven't sampled them myself yet.


Right now I'm favoring Frankoma pottery based on the changes I've seen in my samples. Frankoma pottery is based in Oklahoma and used local clays. In 1953, they began using a brick red clay which is the type that I like. My teas in Frankoma pots seem to be the most fragrant and retain moisture well.

A 2013 Bada Shan sample I got from Camellia Sinensis was very fresh, similar to the photo here.
2013 Bada Shan retail photo by Camellia Sinesis Tea, currently out of stock
The cake is 100 g and magnified quite a bit. You can see it contains some huang pian, but overall the sample I got was very green and tasted very sour. Nothing pleasant about it, so I dumped it into a duani tea caddy for a couple of months, the caddy you see as my avatar photo and again further below. This is a porous clay. The tea did not change in two months, it continued to look green and smell sour, which isn't surprising since the duani caddy is meant for a more humid climate. I moved the sample to this Frankoma red clay honey pot.
Frankoma red clay "Prairie Green" honey pot
After several months in this pot, the tea smells sweet and very malty, yeasty. The color changed from green to brown within two weeks of this storage.
Dry and green 2013 Bada Shan browned and malty now.
Other glazes similar to the Prairie Green shown here include Plainsman and Desert Gold.
Smoky tuos stored in Frankoma 5W Prairie Green bean pot.
Other types of American pottery.
Various samples in small pots.
You know you're old when the pots you made in school qualify as vintage. Two of these are my own creations. Left to right: back left, unknown ceramic containing 2007 Chawangshop Naka ("The Doctor is Naka-erd");  front, white2tea 1992 Big Tao Hong Mark airing in my own pot; back, red Le Creuset stoneware airing wet stored Tea Classico 1980s Ying Ming Hao ("Old Lady Tea,"); front, Tea Classico 1990s Menghai Red Star in my own pot; back right, an abused 2014 Misty Peak spring sheng resting in a chipped gaiwan and recovering.

Santa Clara and Navajo

Santa Clara is a type of black fired clay pot from New Mexico. I stored the above mentioned 2014 spring Misty Peak sample in a Santa Clara pot for several months. However, the Santa Clara did not respond well to humidity. The clay smells like graphite when humid. Pueblo desert type of pottery won't smell like graphite when properly used in New Mexico to store grains. But Wisconsin, my poor Misty Peak tea sample picked up the graphite smell and lost its tea smell. After a month just sitting in a gaiwan it aired, and brought back the smell, but the tea is still very green. I'm holding it for another experiment soon. Navajo pots with glazed interior are usable, but unglazed smell dusty and sandy like the desert if they get moist.

Edith Heath

On the west coast you can find plenty of California pottery from the 1940s-1960s. One really great line to consider is Edith Heath stoneware. This company is still going very strong providing household ceramics and tiles to Arts and Crafts-era homes and businesses. Their prices, even for vintage, are higher than for most other types of American ceramics, but you can buy factory "seconds" for about the same as other vintage ceramics. Heath pieces are very modern and minimalist and I love them. But Edith Heath ceramics proved too porous for my locale. The tea did not retain its humidity and moisture. But this type of pottery might be great for west coast cities with lots of rain. Just enough protection from drier days, but breathable enough for the rainy days. 

Vintage crocks abound on Ebay. About ten years back they increased in value because of the WWII generation collecting what they remembered from childhood. But now this generation has quit collecting and the market has tanked, although many antiques dealers don't seem to see that. I refuse to pay more than $5-40 for these pieces, and reasonable or free shipping. I take advantage of chipped, cracked and glaze craze pieces that collectors don't want.   Still, that beats trying to import jars from Asia that won't work here anyway.

So far I have not had any mold issues, but again my challenge is more about keeping humidity in rather than overly wet. If my tea got very wet, I'd either leave the lids off, or change to another storage method like baskets or porous clay. However, if I wanted to push the humidity I can do so anytime. My Bada Shan sample, and the fragrance and tea texture of my other crocks-stored cakes show me that change is occurring at an acceptable rate, and humid stored teas are able to air without becoming bone dry.

North American Tea Storage Experiment!
Daily Drinkers: "Ding Xing Hao" loose L, at R Crimson Lotus Bulang shous in duani.
What can you do to experiment with tea samples? Nobody wants to ruin a fine cake, but we all have samples lying around from past purchases. Why not see what storage options you can find and use your samples to experiment? I think vintage American stoneware crocks are a real possibility for the long term without worrying about plastics or cardboard flavors in the tea. They create a micro environment which can be controlled with humidity-adding devices like pouch buttons or clay shards for little to no money.


  1. Excellent post and I appreciate the idea of thinking about storage in new climates and contexts than the typical places. Due to Puer tea's history, most of the aged teas that the world has these days are from a handful of places such as Hong Kong, Malaysia, and Taiwan. With more people enjoying Puer in different countries with varied microflora, humidity, and temperature, it will be exciting to see what results occur in the future outside of the now "standard" aged tropes that we have available now. Puer is a tea that can have wide variation and combinations of storage. Maybe some day tea enthusiasts will clamor for "1/2 Hong Kong and 1/2 Wisconsin crock" stored teas. I can't wait to see more pictures and notes in the future!

    1. Thanks for the comment! We are around the 10 year mark now since Internet tea shopping started taking off. So more and more cakes are hitting the 10 year mark outside Asia, and we'll be seeing the results of storage around the world. I will definitely continue posting photos!

    2. I think we are going to have to compare some things in a year or two and see how much difference has occurred in our methods.
      A crock of tea! That's a good one!

    3. Yes, right now I can say this is working out for storage but aging is still to be determined. I'm thinking of doing a real push experiment with one of my teas with a warmer temp and higher humidity. I believe to really crock age tea, the wrappers need to be removed.

    4. I just bought 5 crocks from an ebay auction to try your method! BTW It's mrmopar from Steepster if you haven't figured me out yet.

  2. Awesome, your location will be interesting for data collection! Maybe we should start a Steepster topic.

  3. Fantastic post, instantly bookmarked.

    I have had to think a great deal about this myself this year, and I pretty much ended up concluding that it is not much use for me to buy larger quantities of puer than what I can consume within 1-2 years. Like you I live in a (in terms of puer storage, not much else) challenging place.

    Here in Oslo, Norway, snow has been falling in the morning the last few days (only to melt a bit later in the day), so winter is definitely coming. Right now it's around 20-21 degrees (celcius) inside, with a RH of 40-45%. The RH will drop a fair bit once winter has arrived, heating by electrical ovens and a wood stove definitely won't help, so I expect my cakes to face a tough couple of months. Summers are okay, but very far from "optimal" RH conditions (if lucky it will get to 60-65%),

    So I pretty much ended up concluding that the climate here is simply too challenging, unless one wants to deal with an intricate pumidor system which I currently don't have time for.

    But your post gave me a bit of hope. I'm not sure if I can get hold of jars like that over here, but I'll keep my eyes open. Only thing is I know next to nothing about how to identify the porosity of these things.

    By the way, where do you place the pouch buttons/clay shards? Anywhere inside the pots?

  4. Cywn:
    Thanks so much for this post. I am experimenting with crocks as well, not so much for aging but more with the aim of keeping cakes from drying out or spoiling before I can drink them. I am thinking of purchasing a couple of Ohio Stoneware crocks because I'm not having the best luck finding decent crocks in second hand stores where I live. My question is, is it ok to put different cakes in the same crock, so long as they have a similar profile? For example, could I put Little Walk and Poundcake in the same crock, or do you stick with only one specific type of tea per crock? Thanks!
    Gail (Curlygc on Steepster)

  5. Hello Cwyn,
    I'm slowly running out of storage space, and have found some old glazed vessels for fermenting cucumbers and sauerkraut that I want to try out for my fresh shengs.
    I was wondering about two things concerning your crock storage:
    1. Does the cake at the bottom have contact to the vessel, or do you try to leave some space for air circulation?
    2. Is the lid completely closed or do you keep it slightly ajar?
    I don't think in my case (RH 48-60%, Temp 17-20 C in winter, summer RH 60-80% and T 20-26 C) that it's necessary to add humidity, I'm just worried that the glazed jars encourage mold growth if the lid is closed and the lowest cake is in contact with the bottom of the jar.

    1. I rotate the order of the cakes. It is easy to do this when doing a sniff test. You should be able to smell the tea without a too humid smell. If you smell nothing, no smell at all, the tea is too dry and you can wake it up again with a wet shard or pouch button, or just wipe the inside of the lid with a damp cloth. Practice with sniffing over time will teach you. Your winter climate is on the dry side so you wouldn't have to worry about mold then. In the summer I leave the lid off above 65% humidity. The tea becomes more fragrant with higher temps and humidity. One cake in the crock should be your tester cake. It doesn't matter if the tester is a good tea or a mediocre quality tea. Use it to sample the condition of the tea.

  6. I just got introduced to Puehr(sp?) over the last week and am very intrigued. I also live here in the great frozen Northland but in MN. How are the experiments going? I was glad you took the time to describe your choices and am looking into making some purchases but want to make sure it warrants doing here in the tundra.

  7. Hi Cwyn,

    Thanks for such a thorough and thoughtful writeup of your storage experiments, I liked to use crockware a lot for my puerh as well. I use Boveda packs for the most part, but have some storage containers too small for these to fit / want to start saving money on this part going forward. With the wet clay shard, do you ensure that it's not in direct contact with the tea? Do you let the shard dry off a bit, air or patting it dry, before moving forward? Thank you!!

    1. I pat it dry, yes. Over the past 18 months or so we have had very wet spring, summer and autumn seasons. So I have not used clay shards much anymore. My climate tends to vary more in recent years. If the crock has a lid, I will wipe the inside of the lid with a damp paper towel and replace it, this seems to add a bit of moisture but less than the shard or clay button.

  8. Question: Where do you put the moisture buttons and/or wet clay shards in the crock?
    Do you have enough room to put them on the side, not touching the cakes?
    Do you make a ring of moisture buttons & clay shards?

    I assume that you avoid having contact between the cakes and source of moisture. Sorry if these are obvious questions ;) I would love to try storing my sheng in crocks. Thanks for your fabelous blog.