jscott14 wrote:...
My uneducated vote is that the style of beans you're using simply doesn't create an espresso shot that your tongue agrees with.

^^^^ This


(@mariog7, ever tried Dragonfly Crema Dolce?)

Agree with the last two. The bean is what will carry the risk of sour taste unless something about your technique or equipment is way off. And it sounds like the OP is pretty on top of that, so I'm guessing it's unlikely.

Expounding on what I said earlier, "sour" light roasts are the hotness these days. But if they are expertly roasted, they can still be well developed and full of interesting flavors... IF... your equipment has the capability and you have the know-how to mute the acid enough to reveal the desired flavors.

In that light, it's always worthwhile giving the first seven posts of this thread a read: Lelit Bianca Review

Not to worry. The first seven posts are little specific to the Bianca. They are about the why's and wherefores of having beginning to end control over your flow. It is a seminal piece. I find it worthwhile evert time I read it. In fact, I'm overdue for another read.

-Peter

Here's a simple idea - divide your espresso as it extracts into 4 or 5 shot glasses, catch a bit, then quickly change shot glasses. Now taste each part of the extraction. This gives some idea of how the taste is forming. Last, build your espresso by pouring the parts together, one shot glass at a time and taste how it evolves. This helped me tune the extraction and find the volume I like. It's also interesting to taste the blond and very end.

That's the technique I made a video of here:
And then learned from many others that Chris Bacca had the idea long before me, referring to it as a "salami shot". I still like my name of "core sample" better than salami shot. I don't want to even THINK about salami as I taste espresso.

To OP: some people are indeed very sensitive to sourness. I'm not but I have found many Guatemalan beans to have very little acidity. Usually very sweet stuff. Just to give one example and I'm pretty sure people here promptly point out a ton of acidic Guatemalan roasts/beans

My colleague for example says he can't stand arabica beans at all because too sour. For me that's weird and I think his machine might not arrive in high enough temperature (not your case).

Point being? Try even more coffees?

Just my 2 cents.

To the OP, I have a similar E61 machine and recently came to learn that the location of the temperature sensor does not correlate to a precise temperate at the puck. Turns out, I was only able to really extract a well balanced shot from a medium roast when throwing conventional wisdom aside and raising the indicated temperature to 206 Deg F. This may not help you, but learning that temperature on these machines is estimated has really helped me.

Just an update - I've tried comparing shots pulled at a few local roasters, bringing them home, and I can duplicate the tastes. That means there is nothing wrong with my machine or technique; I can state I was confusing "bright" notes with sour.

I've also upgraded my Lucca M58 this week with a flow control device and found something amazing! My favorite coffee for drip or Chemex is Ethiopian- I love the fruit flavors, but could never stand it in espresso because it is too bright. But using the flow control device and applying a long, low preinfusion, it sucks all the bright notes away and give amazing fruit flavors! So now I know what all the rage is about with profiling and cant wait to try other coffees now.

Thanks for all your posts and help!