I am still in the beginning of my espresso journey, about 5 months in. I have been home roasting and doing some experimenting. I have been roasting Ethiopia Kaffa beans from SM. I have enjoyed them roasted FC and FC+. Very complex and interesting fruity flavors, with an after taste of molasses. I have never pulled anything roasted lighter than FC I would rave about, as they have tasted really sour.

Today though I pulled a shot of Ethiopia Kaffa beans roasted City+. It has an intense but pleasant acidic berry and date taste with a lingering after taste of bakers chocolate.

When I pulled this shot there was minimal tiger striping and the crema look fairly light. If this was not an experiment I would have tossed it in the sink. I am glad I tried it because it was pretty good, but I want to play with the temp. a little to possibly ween the acidity a bit.

My question, is minimal tiger stripping and light crema normal behavior for lighter roasts? Or was this one of those moments that the espresso deities happened to blessed me while the planets aligned?

That matches my experience.

Seems to me acidity is going to be higher the lighter the roast. If you want more sugars, develop it a little more in the roast but slow down the temperature rate of rise post 1c to avoid getting too developed. This is probably a statement of the obvious.

You can brew with hotter temps but I'm not sure what the point is of roasting light to keep lots of acidity then trying to kill the acidity with higher temps.

This old James Hoffman article on foams states that the color of the crema is based on the color of the coffee underneath. I speculate that the lack of flecks in light roasts may be due to these roasts being less brittle in the grind, but that's a WAG.

http://www.jimseven.com/2006/06/13/foams/

It can be...or also an indication of extraction problems caused by machine and/or grind dose. I had a machine in the past that gave me fits with pale (and sour) crema, there are some great resources on here that can guide you in identifying the issue.

From the FAQ section under "Best tips and techniques" I found this (and others) that linked to Espresso: Almighty Crema - Sweet Maria's Library

happycat wrote:That matches my experience.

Seems to me acidity is going to be higher the lighter the roast. If you want more sugars, develop it a little more in the roast but slow down the temperature rate of rise post 1c to avoid getting too developed. This is probably a statement of the obvious.

You can brew with hotter temps but I'm not sure what the point is of roasting light to keep lots of acidity then trying to kill the acidity with higher temps.

Glad to hear that I am not the only one with this experience. I guess light roasts for espresso are another beast of its own.

It was my first light roast attempt for espresso. The contradicting logic is rather to fix a bad first attempt to control acidity. Next time around I'll work on the temp rate post 1c.

yakster wrote:This old James Hoffman article on foams states that the color of the crema is based on the color of the coffee underneath. I speculate that the lack of flecks in light roasts may be due to these roasts being less brittle in the grind, but that's a WAG.

http://www.jimseven.com/2006/06/13/foams/

Thank you for sharing this is interesting. I skimmed though it but will read it deeper later today.

danetrainer wrote:It can be...or also an indication of extraction problems caused by machine and/or grind dose. I had a machine in the past that gave me fits with pale (and sour) crema, there are some great resources on here that can guide you in identifying the issue.

From the FAQ section under "Best tips and techniques" I found this (and others) that linked to Espresso: Almighty Crema - Sweet Maria's Library

This is a great link. I have seen it before. This is why am I am kinda perplexed with my experience. It was light coming out of the pf with light crema, but tasted pretty good. If this is the way light roasts typically behave, some of the crema diagnostics are not applicable, such as the tan/yellow crema = underextraction. If I had pulled the shot described in the OP with a darker roast I would have not even took the time to smell it before it got to the sink, as you mentioned they tend to be sour.

I have no experience pulling light roasts, so I am not too sure how it behaves.