Mitch, I also would like the golden palates to weigh in on this. My experience tells me that if I have a "sour"-tasting shot, that (usually) a higher temperature will help as will (usually) tighter grind/lower dose.

However, I don't think these two actions are necessarily working upon the same taste vector. The temperature may be more about bringing out or enabling "fruit" at the low end versus "chocolate / caramel" at the higher temperatures, whereas the grind/dose actions affect the quantity of bitters - maybe not as a strict dichotomy as with "fruit<->caramels" but only the quantity of the tar / tobacco / leather / smoke complex brought out - really a "more so <-> less so" situation.

(Perhaps the same is at play in the fruit-caramel dichotomy: I have a nagging suspicion that the fruit is always present, but simply buried by the additional caramels extracted by higher temperatures. That is, fruit is not really "brought out" or extracted more thoroughly via lower temperatures, it's just not covered up.)

So I have suspect that the effects of temperature, versus grind/dose, become overlaid and intermixed. One may well cover the other so it seems we're affecting the same item when in truth the two are working along entirely different vectors - maybe not strictly orthogonal vectors, but not parallel ones either.

Anvan wrote: I have a nagging suspicion that the fruit is always present, but simply buried by the additional caramels extracted by higher temperatures. That is, fruit is not really "brought out" or extracted more thoroughly via lower temperatures, it's just not covered up.

Yes, though It is more likely that the bitters are covering up the fruit and not the caramels. Do this exercise: Add sugar to a medium to light roasted espresso and notice that it tastes more fruity.

another_jim wrote:This is how I do it: The grind level is the first adjustment, since it controls the level of extraction. Coarser grinds extract the bitters and sours, as I grind finer, I get more caramels and sugars as well. Once I have sweet versus bitter/sour balanced right using the grind level, I balance bitter versus sour by changing dose or temperature.

Hi Jim, I've read this thread with great interest, but I'm not quite sure I understand Your routine correctly.
Looking at the charts on the first page of this thread, if you are adjusting the grind first You would be changing the flow and acidity/bitterness balance, and then secondly when adjusting the dose You'd be adjusting the sweetness vs acidity/bitterness?!

Hi Jim,

so, is it correct if I say that dosing up achieves the same as grinding coarser, emphasizing acids and bitters, and dosing down achieves the same as grinding finer, emphasizing sugars and caramels?

When You are grinding finer to find the sugar/acid/bitter balance, are you also dosing down at the same time to keep the flow "constant" - and hence changing brew ratio, or are you keeping the dose constant and changing flow-rate? In the latter case, changing the flow-rate would make the shot more ristretto or normal like, which would also affect the balance between acids and bitters and "camouflaging" the original change of only one variable, the grind.

Did I make any sense at all? I'm really just trying to come up with a clear plan on how to explore a blend in a systematic way.