[daveyboy]

Hi!

I like tea. I like tea a LOT. Tannins are bad for you. Binding them with milk means I'm consuming too much milk.

Russians keep the water boiling the whole time the tea is brewing as this somehow apparently locks in some of the tannins.

Can anyone come up with another (food safe!) method of stripping the tannins out of tea. Strong cups of tea make me a productive worker without it I'm lazy.

[Wald_ron]

Stir bar

[daveyboy]

Stir bar

Can you elaborate on that? Like maybe what one is and why it works? I am very interested in chemistry but so busy with work at the moment I don't have time to learn. It's on my next learn list. I would love to have a home lab and make things from every day products just lying around, it's fascinating!

[billnotgatez]

Is this the issue you are talking about?

http://everything2.com/title/Tannins+in+tea


http://www.helium.com/items/1401042-how-to-remove-tannins-from-tea

-------------

I assume that Wald_ron is talking about a heated magnetic stirrer and the bar you use in the liquid

http://www.internationalpbi.it/en/docs/ManualiIstruzione/Arbo-16635-ENG.pdf

http://www.uwplatt.edu/chemep/chem/chemscape/labdocs/catofp/mixpour/mixing/hp_ms/hotstir2.htm

[Wald_ron]

Stir bar

Can you elaborate on that? Like maybe what one is and why it works? I am very interested in chemistry but so busy with work at the moment I don't have time to learn. It's on my next learn list. I would love to have a home lab and make things from every day products just lying around, it's fascinating!

I'm sorry, I guess that I misunderstood your post. A stir bar wouldn't accomplish what you want.

[Grundalizer]

My bad, paste didn't work

[Grundalizer]

Well tannins are chelating agents, and it looks like they bind relatively well with iron, and precipitate out of the solution. 

Here is an experiment you can perform.

1.  Get you're black tea (whole leaves)

2.  Set up two pots of boiling water (or however you make your tea)

3.  Brew two batches simultaneously for the NORMAL amount of time you brew your tea for...say 3-5 minutes?

4.  Pour those two brews into separate containers and make sure you label them  NORMAL-No Iron     and NORMAL- Iron

5.  Repeat the brewing of 2 more batches, but this time brew them for longer than you normally wood, say 10-15 minutes. (The longer you brew the more tannins are released)

6.  Pour those two batches out into separate containers label them  LONG BREW-No Iron  and LONG BREW-Iron

Now as a control you can place some tea leaves in some room temp water and put it in the sun or something, but I don't think its necessary 

IMPORTANT!!! Make sure you use the SAME MASS of leaves in each of the brews, AND THE SAME AMOUNT OF WATER, so the mass of the tea is the same, as is the volume of water (to prevent dilution and varying concentrations).

NOW, you have 4 brews, 2 labelled no iron, 2 labelled iron.

I recommend finding an Iron supplement from the grocery store (tablet form) and then grind up the iron pill as best you can into a powder, and dump it into the two batches labelled IRON.

The reason behind this is that Iron atoms will chelate with the tannins, and form a solid precipitate and fall to the bottom of the cup. (theoretically)

I think you should try this while the tea is still warm (but not super hot as that could interfere with chelation of the iron to tannin molecule)

Then, pour all 4 teas through coffee filters, even the one with no iron added.

Then taste test them and have someone else do it too who doesn't drink a lot of tea like you do.

The one's WITH IRON added should THEORETICALLY be less bitter.  The more bitter, the more tannins you have.  But if the iron takes them out, then yo uhave a more concentrated tea without the bitterness.

good luck

[Grundalizer]

I just remembered that most multivitamins I take taste like crap and are very bitter, so you could just take a tiny bit of the crushed pill and taste test it, if it's super bitter then that will probably ruin the experiment as it will contaminate all the teas and make them bitter.  If it's not too bad, then give it a go.  Also, you oculd look for childrens chewable iron vitamin tablets since they probably taste palpable. 

Second, start with a small amount of the powder added, don't dump in a whole 1 gram pill because I doubt there are 1 gram of tannins in there to chelate it all.

[thedarktwilite]

At my school for the extraction of caffeine we used some sulphuric acid.
The first step was boiling the tea for about 30 min in a beaker and when h2so4 was added all tanins were ppted as a blank gunk at the bottom.