What is in this tea ?

[mael]

Doesn't look super healthy right ? What do you think gives this rainbow colour layer in surface of water ?
The tea is a long jing my sister gifted me after a school trip in china and a visit of Guilin tea institute. Can't remember what brand it was, I left the box at work.
Brewed it in a mug, taste was okay but feeling was strange. The picture is the mug after the leaves sat one day in it.

[Mrs. Chip]

[dizzo]

Nothing good about that imo.
when I see a rainbow on top of liquid I think oil.
That really doesn't look like Long Jing to me either. I wouldnt drink it.

[Aya]

The water color doesn't look anything green tea to me...

[Bok]

You’ll get this kind of film with a lot of standard teas if you leave them sit for long.
Not necessarily a indication of something bad happening, but if the taste is off that is more of a concern.

Certainly not a longjing, leaves should be skinny and long. Colour can be. as any tea will continue to get darker and darker with time, simple oxidation.

Still got the packaging?

[mael]

Still got the packaging?

It is this brand, same box but tea is labeled as dragon well tea (reason I call it long jing + shape of dry leaves).

I was thinking oil was added to the leaves because I found flavor disapeared quickly between first and second brew in the mug.

[Bok]

Might be just the tea oil from the leaves. I got this exact same tea colour and shiny film with the dirt cheap gun powder green tea you get in every Chinatown.

But normally this kind of tea is only for export as the Chinese won't touch it

[Bok]

So it seems this phenomenon is so normal that google autosuggests it, tons of articles about it. Nothing evil:
https://www.theguardian.com/lifeandstyl ... k.features

[Bok]

And a whole old thread on it on teachat as well: viewtopic.php?f=1&t=1552

[john.b]

Interesting references Bok, thanks.

That article and the responses aren't completely consistent but they mostly say a rainbow colored scum on a tea is probably just due to minerals, nothing to worry about. I'm not sure I'd find that reassuring enough to drink it.

The tea is supposed to be longjing but it looks kind of brown, both the leaves and the brewed liquid; I'm not sure about that part. Aged green tea will continue to oxidize and turn brownish over time, and I have some at home more or less aging as an experiment. Three years along it's a bit tan but not dark. You might try to get one of your co-workers to drink all of it and see what happens to them.

[Bok]

Sure thing.

Important to note that green teas from China are not 100% green as their Japanese counterparts. Still pan fried or otherwise oxidised. So already more yellowish. If left overnight and I assume it is low quality tea, than the colouring makes sense to me.

[mael]

You might try to get one of your co-workers to drink all of it and see what happens to them.

hehe I should give it to my boss he told me he likes tea

Water is indeed quite brown but it is after 1-2 day of sitting in a very low amount of liquid. Water colour was okay during brew.

I will make experiment with other chinese green teas and see if same oilish layer appear on surface, a few long jing and other green teas from life in a teacup that are better quality. Parameters are not hard to replicate.

I will let you know the results

[dizzo]

Thanks for the Reference Bok.
Perhaps I have never experienced this because I always rinse my teaware when done. Ill try an experiment and let a few Long Jing leaves sit for a few days.

[cheefai7]

It doesnt look like LongJing to me, too brown to be good to consume. If have doubt, and not feeling comfortable with it, stop drinking then.

[Bok]

It doesnt look like LongJing to me, too brown to be good to consume. If have doubt, and not feeling comfortable with it, stop drinking then.

After two days in a cup all tea looks brown