Yellow Mold again???

[VanFersen]

Just for the Background it is a Laos Sheng Gushu from 2014 so a very fresh one. I was wondering why this always happens just to the fresh Sheng stuff I mean in my case it always went wrong with those types of Pu's never with Shu stuff.

[apache]

If a cake is tightly pressed you might see yellow dusty particles when you break it up. Put those particles in hot water, if they are broken fragment of leaves, it will expand and you could see they are indeed small pieces of leaves.

[VanFersen]

And this is exactly what I was thinking about "Is it mold or is it just some flower stuff?" But how is it possible to be sure about it (DON'T TELL ME PCR )

I mean in this case here (a picture of an older cake I throw away because of obvious yellow mold) I was sure about the mold :



but the one now we are talking about I not 100% sure if it is flower or mold.

[Drax]

Do you have a microscope, or access to one?

You might also be able to try to take the mold and grow more of it. If you can, it's mold (if it's the same stuff), and if not, it's inconclusive.

Unfortunately, there's no way to know for sure, other than more scientific methods (or if a mold expert manages to see this pictures... but even then, I think better pictures will be needed)...

[Poseidon]

Let me start off by saying that I have no expirence with this issue.

Could you put a bit of the yellow "mold" onto a dish and let it sit in a warm place to see if it reproduces? Essentially, you would be creating a home incubator. As for temperatures and what not, Ill leave that to google or one of you science brained people.

[BW85]

Flower/flour/dust?

[VanFersen]

The seller sended me some makro pictures and he took them from his other half. It looks the same but now you can see it better and it seems he is right. He said it is a flower or something that's between the layers and you can see it because it goes vertically through the whole thing. And because of the Pu breaking it was broken and the dust covered the broken parts. Or what is your opinion?

[Evan Draper]

Let me start off by saying that I have no expirence with this issue. Could you put a bit of the yellow "mold" onto a dish and let it sit in a warm place to see if it reproduces?

Ditto that. Yeah, I think it's mold, but I'd also be drinking it if it tasted ok. Why do his photos look so yellow--TO DISGUISE THE MOLD?!?!?

EE you should do a tea PCR blog series. I sent some samples at personal pain to a prominent tea scientist who promptly stopped returning my emails.

[entropyembrace]

The seller sended me some makro pictures and he took them from his other half. It looks the same but now you can see it better and it seems he is right. He said it is a flower or something that's between the layers and you can see it because it goes vertically through the whole thing. And because of the Pu breaking it was broken and the dust covered the broken parts. Or what is your opinion?

Some problems:

Why would there be a bunch of flowers pressed into the cake? What species are they? That's not ordinary and when it's done it should be clearly advertised.

Why were the pictures taken with such poor white balance such that it hides any yellow inclusions?

If it really is flowers pressed in the cake where are the rest of the flower parts? There is yellow dust and yellow...fibers? The dust alone would be hard to distinguish from pollen just by looking at it but...

Those fibers really look like hyphae from a fungus to me

You can see a couple of tea cakes with flowers pressed into them here and they don't look the same: http://yunnansourcing.com/en/134751017- ... erbal-teas

You could try brewing your tea and looking at the wet leaves to see if any of that stuff rehydrated obviously looks like bits of flowers. Also does the tea have a strong smell?

[entropyembrace]

EE you should do a tea PCR blog series. I sent some samples at personal pain to a prominent tea scientist who promptly stopped returning my emails.

I'm not sure how much I could contribute to that in reality Using PCR for species identification is something I've read about your lecture based classes and not done myself. The lab I'm doing my research project in uses PCR in making fusion proteins to act as markers to visually distinguish different types of immune cells in living tissues and cell cultures. And RT-PCR to monitor gene expression.

[miig]

I think this might be an euphemistic description of mold. There are certain brick teas ("Fu Cha" which have a certain kind of yellow mold, which becomes visible and is called Jin Hua, Yellow Flowers.

BUT these teas are deliberately produced in a way that promotes the cultivation of these specific mold cultures, and if I'm right in that what you bought is a normal 2014 sheng, it shouldn't have these!

Second, I'm anything but an expert in Mold tea, still i think these Jin Hua look rather like little stones, at least in the pictures I saw and on the 4-5 different Fu Chas that I have. They never seemed to be furry like the things on these pics are, and this means that I wouldn't count on it that it has anything to do with Fu Cha.

If you're interested: Some info on these:

http://www.teachat.com/viewtopic.php?f=1&t=17858

http://hojotea.com/item_e/d01e.htm

[puyuan]

It may very well be that the pictures are deceiving me, and better qualified people have already chimed in saying otherwise... But judging from this picture alone - http://s120.photobucket.com/user/VanFer ... 9.jpg.html
I don't think it's mold at all.

I've seen young cakes with this look a few times. I think I have a 2014 wangong sample that has it, and I'll see If I can upload pics for comparison. My guess is huangpian/debris. Have you seen how everything looks once hydrated?

[Evan Draper]

EE you should do a tea PCR blog series. I sent some samples at personal pain to a prominent tea scientist who promptly stopped returning my emails.

I'm not sure how much I could contribute to that in reality

Thought so, called your bluff! You're welcome, VanFersen....

[entropyembrace]

EE you should do a tea PCR blog series. I sent some samples at personal pain to a prominent tea scientist who promptly stopped returning my emails.

I'm not sure how much I could contribute to that in reality

Thought so, called your bluff! You're welcome, VanFersen....

not that it would be hard to do with the primers and probes kyarazen posted. The same thermocycler, DNA extraction kit, and gel electrophoresis setup that I've used for other things would work. PCR gets used for lots of things with very little modification. The same hardware gets used in lots of different labs working on totally different things.

But would I want to setup a blog and take lots of samples of weird stuff in Pu in the mail and try to ID them? uhhh...no, and my supervisor would get annoyed at me for running reactions that have nothing to do with immunology all the time If it was my own tea and I said "hey can I buy the primers myself and see what this is?" I'm sure that would be ok.

Go knock on the door of an environmental microbiology lab, they'd probably have the primers in the freezer and be directly interested