Hey all, looking for some tips on the above. In general, which recipe should i use to lessen the bitterness if i am aiming for 38-40g of coffee from medium-light beans. I do switch between regular brazilian and african higher attitude beans.

Right now i am using 18g, 5s preinfusion, 28-30s extraction at 9-11bar, i stop at 38g. Flow looks good, no channeling i can see, puck is evenly colored except the outer bottom part where the lelit basket holes do not go edge-to-edge

But this seems to give a bitter lingering taste to my guests. For me, i do taste the slight bitterness, but it is not something nasty or tarty. It is very drinkable and way better than starbucks burnt coffees.

But i do find such aftertaste overpowers the floral flavor of african beans too fast.

I try to lessen extraction time to pre 5+25s pull, it still have the tinge of dark bitterness that overpowers floral. Or is this normal and the floral mouthfeel should not be coating and lasting? I set the temps at 95c, so the group head is probably 90-94c

adjust opv to 9 bar. if its easy to do you can try 10 first.
if thats hard, try 93degrees instead.
good luck.

Definitely try lowering your temp. Try first 93 degrees. If it is still bitter, try 92 degrees.

what are the good temperature range for brazilian and african beans, medium lightish roasted.

I thought such beans should aim for higher temperature.

Does a lower temperature allows us to pull a shot longer, with other variables the same, without burning/bittering a shot?

DaniPGK wrote: extraction at 9-11bar,

Your pressure gauge swings from 11 to 9 bar during a shot? That is the first problem. Do not know what machine or grinder you are using but it sounds like you need to adjust your pressure down. You should be running 8-9 bar pressure. If the pressure swings several bar during the shot you have a channeling issue which could be many things.

Oh it is an economy lelit grace, i think the manometer jump to around 11 when i turn on the machine, and then stablised around 9 or 10 readings depending on type of coffee i use.

I would play with the normal route of being less bitter. What you can do right away is change the ratio. Instead of wanting 2:1, go to 1.5:1. Temperature does have an effect but it needs to be a big swing to make a sizeable impact. I'd try that first before playing with grind size. Sounds like you are pretty close.

Look up an extraction chart to see how to extract less. Lots of ways to do it...

Since you seem stuck, just go crazy and try and under extract and make it sour. Then you will know the other extreme and it will be obvious what to do.

Under-extract by shortening the time/less yield and keeping things constant. You tried this but only 3s, you can do a 20 or a 15s shot for 20g if you want.

Alternatively, grind coarser and keep the same yield as before, then slightly lower it each shot until it's not bitter. Personally I would do same amount it, coarser grind, and 30g out in way less time.

Adding a teensy bit of salt - I know one person who adds just one grain of kosher salt - is supposed to dull the tongue's ability to detect sour. Way less than the level that makes the drink taste salty. Every tongue is unique, but at least for me it does wonders in a pour-over.

You could also try fractionating your espresso shot into 3-4 cups (I use shot glasses) and taste how the shot evolves over the course of pull. I just line them up under the basket and push them across as the shot proceeds.

Do you think that bitter late notes that my guests spoke of, is because we are using the Niche Zero grinder now?

I saw some reviews content that claims NZ produces a slight bitter tinge than higher end flat burrs grinders