A Furry Brick

This morning, my eyes nearly popped out seeing these fuzzy white hairs growing on this tasty 06 Lucky 7581.  How? What? When? Why?

I give my shengs frequent visual and sniff inspections multiple times a week mostly to check for signs of life. The Bay Area being touted as a dry god-forsaken place for aging, I have to obsess about teas drying out to mummies.  However I haven't been too diligent about my shus which do okay in this low humidity.   

This neglected brick had been stored just only in an outer basswood box in a loose opened plastic bag mostly to keep the crumbs together. The last time my eyes laid on this brick was probably two years ago.  All the panicky thoughts raced through my feeble mind. What else got contaminated? Should I never be using a plastic bag at all? What about my idiotic new sealing strategy!  What about Saint Hojo of Sealed Pu?

I couldn't just open up my other shus then and there to do a mold check in case contaminating spores became airborne.  I ran a HEPA air filter for a few hours to clear the air.  While I was waiting,  I looked for options to identify this white mold while brewing up some of the unfurrified chunks (the mold appears not to have improved the flavor).   I considered DNA analysis but the test only looks for Stachybotrys /Aspergillus/Penicillium molds that are commonly found in homes.  If it's not one of these, then I just wasted $62 dollars.

If DNA is out, then microscopy and visual identification was the next option. The only microscope rental service I could find was UC Berkeley's Electron Microscope Lab which would be over-kill.   I opted for the more flexible option of my very own digital 500x microscope which will arrive mid next-week. Before I casually take a toothbrush to this brick or chuck it altogether, I just want to make a final attempt to identify this white fuzz which looks similar to the fuzz I found in the shu stored in the ceramic jar.

After the air had been cleared, I opened the shu brick box and the other tea were completely pristine as much as shu can be.  I checked every single item of shu some of which were also in open plastic bags for containment and everything was clean.  I've had shu samples from multiple vendors in plastic pouches for years without any mold trouble.

So in the nine years of storage, I have had two mold incidents- one involving shu in a closed ceramic canister and this here brick.  This brick must have had more initial mold before it came to me than any other shu I've got- i.e. the furry white mold was already dormant in the brick and not seeded from my house. I will use only paper or wood storage for shu except the samples in their plastic bags for now.

For the sheng's which I store mostly in basswood boxes, the few that I put in closed plastic bags I've opened the seal and will monitor them closely.  I cannot wait to get my hands on the digital microscope to give my pu a full inspection. 

I was so distressed today that my sweet husband tried to cheer me up with oysters.  I greedily gobbled up more than my fair share.

Fifteen Flaws of Poor Puerh

When you enjoy your tea, your spirits soar.  You can shoulder all the world's burdens drinking such tea.  When a puerh royally disappoints, it merits some investigation as some shortcomings can be overcome. Really, if you have an entire cake of something disappointing, you had better figure something out.  A poor brew could stem from flaws inherent in the source material, or defects introduced during the processing or storage stage before it reached your teapot. Let us consider the many and various ways a tea can land you in regret city.

1. Undesirable off flavors -  deal breakers include residues from  pesticide use and gag worthy mold taste from poor storage that for love or money you couldn't rehabilitate.  Cigarette smoke and metallic aftertastes are lesser offenses that may respond to airing out or repeated rinses.   We'll just consider barnyard flavors in shu as an artifact of the processing and not an actual flaw as such although being a shu is a flaw in it of itself is it not...

2. Harshness - Kick in the face and/or a kick in the stomach, it burns your pipe all the way down. It could be a kick in the nuts but I wouldn't know. Why do some drinkers seek out that kind of abuse? It's not like the world generally recognizes masculinity or strength in those who can down an entire pot of aggressive young Bulang. But most importantly will aging tame the harshness? 

3. Wrong kind of bitter - Without the redemption of huigan, there's no point in enduring bitterness that ends in just more bitterness. 

4. Weak - Autumnal productions are often lacking the vigor of their spring counterparts but plenty of productions labeled as spring picked have pooped out in just a few brews.  There's seemingly okay teas that peter out after a few brews and there's teas that brew weak-ass all the way.

Strangely, I've had weak teas that were still strongly offensive - watered down manure is still potently gross.

5. Thin - you need not chew your tea but a good puerh has a full-bodied viscous mouthfeel that coats your throat.

6. Flat  - actually the world is full of monotone single note teas, that's why we drink puerh.

7. Sour - a little lemony citric tartness could be charming in a young tea but too much sourness can mar a tea session.  From the bannablog,  I found this informative tidbit:

"Sourness (Suanwei 酸味): can arise if, after rolling, the tea was not dried properly and pressed while still wet, moisture develops and it becomes sour."

8. Dry/Astringent - Some XG fans might not consider mouth-drying powers of a tea an actual flaw.   The medical uses for such tea have not been fully exploited.  They use botulinum toxins(Botox) to control drooling for conditions like Parkinsons but a brand new Xiaguan tuo probably would be twice as effective, cheaper and less invasive.

9. Stale - all tea have an optimum window for consumption, and there's no regret like letting a tea go stale.  Even puerh is not immortal and there is debate over the shelf like of shu.  I've got a 2002 Feng Qing ripe which just doesn't taste as lively as it did even a few years ago.  Stale tea can be the cause of thin, flat, weak tea. But no shortage of non-stale tea can also share in these qualities.

10. Over-processing-  Sometimes when Hobbes gets riled up about suspicious red brews from over oxidized sheng that taste like hongcha, I wonder what he is going on about.  I've personally have never gotten my panties in a twist over shengs that taste like hongcha but I kind of like hongcha.   I however have run into way-over roasted oolongs where you might as well brew lumps of charcoal. Shus are particularly prone to over-fermentation where the brick is best employed as a compost a kick starter.

11. Finicky- perhaps the tea is amazing but it requires condensed Wuyishan dew heated to exactly  174 degrees over a bamboo charcoal fire brewed in a zhuni pot then served by enticing maidens.

  

12. Overpriced- Insult to injury if your sucky tea was procured for a goodly sum.  It feels even worse if the terrible tea came to you as a gift.  Value for money mediates your disappointment as some flaws are tolerable if purchased for a beggarly sum.  I have no shortage of dirt cheap beengs that are boring and for the price, I don't hold their utter mediocrity against them.  

13. Fake - White2tea has an excellent post on the vagaries of misrepresentation in puerh.  Personally if the tea is good, I don't care  as much unless I paid a premium based on the false claim.  But it's nigh impossible to avoid some marketing upcharge in puerh.

14. Overhyped - While you cannot avoid some level of gushing from the vendor,  when every blogger and their teapet are yukking it up with the tea du jour, it's worse to have your raised expectations be floored.  You think to yourself, was it your poor brewing? Did you just get a bum sample?  The web is a diverse enough environment where your contrarian experience can be confirmed, but it doesn't erase the sting that others are having a grand old time while you lurk in the shadows of discontent. Of course you might be exactly the kind of person that revels in dissing a popular tea.

15.  Well- I leave that up to you. I hardly could have found all the dirt on puerh.

Despite such grumblings and grousings on my end,  wading through the minority of sucky puerh is worth all the trouble and more.  Truly atrocious puerh is rare and I challenge you to find a tea which embodies all 14 flaws.

Good Mold Bad Mold

Fellow tea drinker Mat from Germany generously shared with me the paper "Identification and quantification of fungi and mycotoxins from Pu-erh tea" which I've read and reread to exhaustion.  Instead of contemplating the bucolic views from this lovely treehouse yesterday,  I hunkered down with this stiff yet illuminating scientific paper which offered a few nuggets to chew on.  Much to my husband's delight on our anniversary weekend, I kept going on and on about mold and mycotoxins but he is used to my ways and is most willing to pay the price of admission as they say.

 (This off-the-grid treehouse had strict rules forbidding fires of any sort so I resorted to drinking pre-brewed aged oolong lukewarm in a thermos.  Experience of sleeping three stories up in a tree felt very different than what I had imagined as a little girl.  A living tree creaks and sways constantly and if I were to build my fantasy treehouse, I would build it in the shape of a boat.)

This study published in the International Journal of Food Microbiology took 36 different puerh samples (25 loose tea of organic and conventional production, 11 compressed) and tried to isolate and identify the molds and mycotoxins present. The study does not explicitly indicate whether shu or sheng was used but I assume they used all shu samples as the authors describe the wodui process in the introduction.

The authors found no less than 31 different molds with compressed samples being less colonized than the loose shu.  Aspergillus acidus was identified as the main beneficial microbe in fermentation. Not all molds are beneficial and the study was looking for contaminant molds which could potentially produce cancer causing organ destroying mycotoxins.  The study specifically targeted the following three fear-inducing baddies- aflatoxins, fumonisins, and ochratoxin A(OTA).  I'm happy to say that only OTA was found in extremely insignificant amounts in only four of the loose shu samples.  

How do these findings translate for the puerh drinker?  One- it's always good news when mycotoxins are not detected in your favorite brew especially by those who might benefit by doing so.  Three of the authors of this paper work for R-Biopharm that makes an Aflatoxin screener and so they would have had cause to try to find toxins in puerh. Two - you could rinse your pu at least twice but note mycotoxins are not water soluble and not all fungal spores are killed by boiling.  Three- it appears there is more contamination risk in loose shu than compressed forms.

So what should you do when you encounter white furry hairs growing on your pu?  I keep small amounts of shu in ceramic jars to mellow out before brewing and this 2004 CNNP had developed a patch of white mold more than a year ago.  Yes, even in cold dry Berkeley, this can happen even without the aid of a pumidor. This mold is pretty slow growing as it barely doubled it's size in a year.   I couldn't bring myself to pitch it and kept it in the kitchen in case the taste developed into something special.  

I tried to look up images for the molds in the above table for compressed shu. You can see that fuzzy stuff under macro is seriously filamentous white mold that hasn't fruited.  I almost expected a tiny little spider to be doing a brisk business down there. I will need a more than a powerful microscope to be able to identify this bit of fuzz.

I read on tea forums that white mold is not cause for alarm and can be brushed away.  But when encountering visible mold without positive identification, each tea drinker must assess their personal level of comfort in risk taking depending on their current health. Pregnant ladies and those with shot immune systems should take caution.  But those willing to take the risk should consider the payoff.  I brewed up the unaffected bits and it was boring old shu with the slightly metallic opening taste that did not get that much better.   I pitched the rest.  Had this been a twenty year old specimen with magical taste, I might have soldiered on.   

Fermentation is Mold Magic

The web is full of stern admonition that boring low-grade sheng becomes boring low-grade aged pu.  But anyone that's ever tasted sauerkraut knows that boring sad limp cabbage can still transform into something wonderfully complex.  Why can't boring factory sheng transform into a mouth pleasing tongue tingling brew through the magic of fermentation?

No shortage of bloggers including myself have been disappointed with poorly aged stomach killing teas.  What could have gone wrong there?  Let us postulate ever so unscientifically as I am fond of doing in this blog.

Puerh fermentation rests on bioactivity of beneficial molds. Yes molds!

I've read in various studies that some of the following micro-critters are responsible for fermentation in puerh:

• Aspergillus acidus - picture taken from NIH above.
• Aspergillus fumigatus - not a friendly bugger. It's the mold commonly found in compost piles and can cause repiratory infections in individuals with immunodificiencies.  I really should think twice about huffing shu so indiscriminately.
• Zygomycetes - is a pathogen rather than a friendly fermenter. Must read paper and update...
• Penicillium - ditto
• Aspergillus Luchensis - tasty koji mold

It's clear even a tiny chunk of puerh is a microbiome where various colonies of fungi eke out a balance. Just as sauerkraut fermentation can be ruined when the wrong kinds of bacteria and molds taken over, perhaps the badly aged tea suffers an imbalance of beneficial fungi. 

The paper I am hot to get my grubby paws on (Identification and quantification of fungi and mycotoxins from Pu-erh tea) mentions that 4 out of 36 puerh samples contained the dreaded mycotoxin Ochratoxin A. Ocrhatoxin A produced by unfriendly mold is a carcinogenic as well as a neurotoxin that may give you nightmares about pu drinking.  Actually Ochratoxin A is so prevalent in the food system that there is actually a TWI (Tolerable Weekly Intake) guideline esblished with some foods like licorice and ginger having elevated amounts. I probably ingested some today. Whew.  No need to give up my pu.

I'm so curious about the tea taste value of those 36 samples? Did those 4 teas taste differently in a negative way or were they still palatable or even interesting?   

Last weekend in the car I asked my husband, "Why do I like tea so much?" He said without missing a beat, "What's there not to like."  

UPDATE 9/4 Mathias has most generously shared the mycotoxin paper mentioned. My walnut is exploding with so much excitement.  Dear reader, I will take this weekend to digest this paper and report back to you. 

Hydration before Sealed Storage

(9/26 Addendum - This has got to be one of worst experiments that only led to moldy tea. Please see my post on mold diaster.)

For those living in cooler drier climes, there's a persistent and real threat of poorly aged flat-tasting near-dead puerh.  How far do you want to go to give those young shengs what they need? As far as I can tell, pumidors appear to be a time-bomb for unwanted mold incubation- not to be attempted by someone as absent minded as me. (Last month I hired a cricket chorus as pets then completely forgot to water them one hectic week.  They only last a few months so I couldn't tell if they had come to a natural end or I did them in.  I only console myself that they lived a nicer month in a well-appointed terrarium than if they had gone to feed a hungry reptile. )

I spent all weekend sniffing and sampling a few decade old teas. Results are not terrible but not great either.  The sheng is definitely aging here in Berkeley albeit slowly- but it lacks depth compared to cakes aged in the hot and humid places of the world.  I'm definitely not buying any more new born sheng to age. It was all fun and games to stockpile them when they were ~$10 a beeng eight years ago but the stakes are too high now. Where to next?

Despite the various controversies over sealed storage, I'm coming to the conclusion that sealed storage works better for my particular situation.   After contrasting teas that have been stored in varying degrees of air tightness (mylar bag, plastic bag, tin, looser fitting basswood boxes, ceramic jars and chipped teapots), it doesn't appear that the sealed teas are aging any less than those unprotected inside my enclosed cabinet.  I think the water content of the tea before entering their sealed state is the more critical factor.  The sealed teas definitely retain more of their volatile tea fragrance and liveliness; my nose being the organ most suited to appreciating puerh these days tells me sealing is the way to go.

I had been using a glass cake dome as a conditioning chamber which I dubbed spa sheng therapy.  When Israel generously shared with me his  EoT samples from cold dry Montana, I did not smell anything off these chunks for over a year.  I had tried to revive them two years ago but either it was too cold in October and/or I gave them too brief a stint under the dome.  I recently started re-hydrating them for weeks at a time and sealing them back up in a plastic bag- the fragrance has happily returned and has remained.  Despite the reading on the hygrometer showing 70% relative humidity, it fluctuates under the dome to go even as high as 80%.  I've been able to almost beat the smoke out of the cigarette beeng under this dome.

I had been pondering over what to do about my storage situation when Cwyn of the newly minted deathbytea blog wrote me to say she has had some positive results in Wisconsin with ceramic storage.  I've been curious ever since I saw Petr's lovely unglazed storage jars and Gero's terracotta setup. I've tasted shus improved with such storage but I have not attempted to do so with shengs. ( I squirrel away tea anywhere with a lid including broken teapots.  That's some trad stored pu hiding in the sugar bowl I inherited from a friend's grandmother. I bet her grandma never imagined such smelly gnarly shu would be living in her precious Spode.)

In maintaining a humid environment inside a jar, I would still have to fret and obsess about mold.  Temporary boost in hydration before sealing up the tea is the lazier way to go.  For now I just need more hydration chambers. I ran out today and managed to find two cheap ceramic casserole dishes at a thrift store.  I know what you are thinking. The ugliness of these pots can deter the tea from absorbing moisture properly.  I have no shortage of desiccated tea to experiment with and any hit of humidity is better than nothing. I'm loading up this 2004 golden melon which has been living in a puzzle tin. It actually smells more aged than those stored open on the shelf and the taste while not praiseworthy is aged enough not to give me gullet trouble. That teensy bit of progress actually made me feel hopeful all weekend.