[peaxkl]

For me using the cold brew method instead of cooking the leaves had the biggest effect on the bitterness.

The taste goes in the direction of ClubMate, but has a stronger tea taste than the original ClubMate. I think reasons for that are the reduced amount of sugar and the fact that ClubMate uses natural flavor in their tea extract.

[whywhywhywhy]

Isn't this a tannins issue? I've not done mate before but with black tea my understanding is brewed tea cooled down is bitter while tea just left in cold water in the fridge is smooth because brewing it releases tannins.

[IAmBroom]

Water-soluble taste compounds all dissolve with similar time profiles (all other things being equal), which are exponential curves that asymptote at zero and saturation. The time constant and the saturation level are the true variables, and saturation is "chosen" by the molecule itself, but when you superimpose exponential curves, a slower-dissolving "bad" taste can be minimized by finding the right balance point between "enough" of the good solutes before the unwanted solute rises much.

"All things being equal" = that time constant is itself a function of temperature, so lower temperatures slow down (spread out) the process, allowing a broader "balance point" at which to stop the process.

IOW, if you're brewing a hot cup of tea, leaving the bag in an extra few minutes can really increase the bitterness without making it much "darker", but even a few extra hours in the fridge-brewed tea is no big deal.

[lopis]

Buying different brands will change the taste even more.