>>18I boil it and let it cool for a bit before making it, so just post-boil cooling, I should say. What do you mean by taste? You could have failed to mix it properly or even mixed it too much. How did you store it? I'm still keeping mine in the resealable tin sitting inside a wooden box with the bowl inside. Smell the powder, look at the texture, feel the powder. It should be like coarse sand, it shouldn't run too much or stick together.
It could even be expired already. If you're in doubt, get a new tin to be safe.