Different Bean - Different Grind

#1: Post by **lbdina** » August 31st, 2015, 11:07 am

I know each bean grinds somewhat differently and requires some micro adjustments on the grinder. Occasionally, however, I run across a bean (or blend) that requires a major grind adjustment. I recently did a roast of Sweet Maria's Mocha Kadir Blend (Yemen, Tanzania, Uganda blend) and using my typical grind setting, espresso blasts thru my espresso machine like a fire hose. It runs very fast, even with a heavier dose. I always use the WDT and tamp the same. I do most of my roasts to the same level, following the same times and profiles, and nothing else was changed during roasting or shot pulling. This is not an anomaly, because I had the same experience with this blend about a month ago when I roasted it. Coffee is fresh, 1 week post roast. When I go back to different beans, my typical grind setting is just about perfect, so I don't think it is my grinder (Baratza Preciso).

I'm curious why the grind for this particular blend needs to be so much finer than most of the other beans I roast. Is it amount of fines, the hardness of the bean, the growing altitude, phase of the moon, etc? I'm sure someone has opinions or facts on the reasons. Looking forward to your thoughts.

Thanks,

Lou

#2: Post by **cmin** » August 31st, 2015, 1:11 pm

Some beans can be tricky, what was your roast like? The Preciso doesn't like lighter roast. Example, I had various beans from Populace and they were about impossible to pull as espresso, dialed way down on the Preciso from where it normally is for everything else and wouldn't work and actually jammed, Vario I had to dial way down as well and even tried re-calibrating it and wouldn't pull good shots they were mostly gushers or sprayers, friends Compak K8 had the same issue and he's never had to dial down as far as he tried couldn't get the beans to work. Think it was 4 different single origins if I recall. The beans were really light, and others had trouble so not sure if it was b/c it was really light roasted or something else was off during roasting but I would assume that would be odd for 4 different beans could see one batch being bad etc).

#3: Post by **brianl** » August 31st, 2015, 1:34 pm

I find this mostly happens with beans that are not properly developed (I also had those populace beans cmin mentioned and last week I received something similar from my normally excellent local roaster). When these were brewed up with a filter brew they were largely boring and muted.

I can also tell right away by how hard it is to grind on my HG One. I never have good luck with these beans for espresso. Perhaps this is where a big flat grinder would be best.

August 31st, 2015, 3:52 pm

Thanks for the responses. Roast was Full City, before second crack. I really don't think it's the grinder. I don't think it was development either...I had 3:07 minutes development (25.2%) in a 12:23 minute roast. I could be wrong on both counts, but nearly all my other roasts work fine and require only minor grinder adjustments. It's only this particular bean blend, and it has happened twice. Most of my roasts are FC, dropped before second crack starts, approx 13 minutes long, with fairly long development (25-30%).

A clue I forgot to mention in my original post...these beans grind much faster than most at the same grinder setting. So, it if takes me 10 seconds to grind 15 grams with most roasts, I get about 18 grams in 10 seconds with the Mocha Kadir blend. So, are these softer, less dense beans? Or do I have that backwards? Would a change in hardness/density require a substantially finer grind? Does bean size also affect grind speed?

It's not a big deal, because I am able to adjust my grinder so it works fine with these beans. I'm just trying to understand why this particular blend acts so differently.

Thanks again.