Getting lots of bubbles forming on first few infusions of possibly fake Shui Xian?

[m2193]

I received this tea that was labeled as Lao Cong Shui Xian as a gift from an aunt. It tastes very burnt with not much else to offer (doing short gongfu steepings with filtered water off the boil), so based on the seller descriptions I've seen online, I'm guessing it's likely a fake. But what's concerning to me is that this is the first tea I've tried where I've seen so many bubbles form as soon as water is poured onto the leaves in the gaiwan. I've heard that sometimes happens with green teas, but I don't drink those too often, and I've never seen any bubbles in the oolongs I've had in the past. Is this a common occurrence?

[Victoria]

I had a similar issue with a roasted high mountain oolong and posted about it. In the thread there are a few causes mentioned, both having to do with mineral components;

Yesterday, I had a mystery roasted oolong that foamed a little on the first two steeps, and also had what looked like an oil slick on the surface of the liquor. .....Any idea what causes foam and an oil slick?

could it be mineral residue from brewing with hard water?

Here is an brief account of tea scum: https://www.theguardian.com/lifeandstyl ... k.features

The linked Guardian article mentions....“The scum, or at least 15% of it, is calcium carbonate - the rest being a lot of complex organic chemicals.”

[m2193]

Huh, interesting. I've always used Brita filtered water (though at home, the water is pretty hard locally) and haven't had issues with any of my teas in the past, so I thought it was an issue just with the tea. Thanks for the link and info! @Victoria

[Victoria]

Huh, interesting. I've always used Brita filtered water (though at home, the water is pretty hard locally) and haven't had issues with any of my teas in the past, so I thought it was an issue just with the tea. Thanks for the link and info! Victoria

I also use Brita filter tap and had this happen only once so far. Strange and foamy .

[LeoFox]

Brita seems to decrease tds by 20 to 30. So if your starting tds is 300+, even triple brita filtering will have little effect.

[esontea]

It is normal for a layer of oil to float on the surface of roasted tea. This is the vellus hair on the tea. You can look carefully at the top of the tea, there will be fine impurities floating on it.

As for the foam floating on the tea leaves, it may be caused by the high content of tea saponin or the more vellus hair.

[m2193]

Brita seems to decrease tds by 20 to 30. So if your starting tds is 300+, even triple brita filtering will have little effect.

That's a fair point. I've just never had it happen before with other teas I've brewed (whether oolong or not), so I wasn't sure.

[tjkdubya]

Some people anecdotally talk about excess scum formation with over-fertilized yancha but this is not something I can confirm. I do see the tendency of excess scum formation more often in cheaper stuff.

If the OP is seeing a deviation from their usual experience, assuming they use the same water all the time, not unreasonable to assume what's up with the tea...