Advice on recent espresso brew issue

#1: Post by **kwongheng** » October 2nd, 2016, 5:32 am

Hi all,

I need some advise on the recent espresso bean which I am using. First a quick list of my brew equipments:

Grinder = Baratza Preciso
Machine = Expobar (office) Leva with stock double spout portfilter

Beans = Espresso roasted single origin from Brazil, Sitio Tanque

Beans in = 20 g
Weight out around 40 g
Time = 19s

For this particular bean, I have my grinder to 0B position (0A is the finest!) on my grinder, but I am still getting under-extraction. The shot is highly acidic, with no bitterness, body is pretty weak (to me).

TDS = 8.86% with calculate yield of 17.72 %

That is maximum extraction I seem to be able to get out of the beans. Is that possible? Does it mean that I cannot grind fine enough for this beans?
Note: I have not problems with other espresso blends or single origins previously.

#2: Post by **samuellaw178** » October 2nd, 2016, 7:30 am

kwongheng wrote:Beans in = 20 g
Weight out around 40 g
Time = 19s

Instead of focusing on extraction yield, the shot time/flow rate indicates the Preciso is not able to grind fine enough. You need to calibrate it to grind finer. There is a possibility the plastic collar is broken (coarse grind is a symptom) and needs replacing - this happens more often with hard dense light roasted beans.

#3: Post by **dilin** » October 2nd, 2016, 8:40 am

Did you clean the outer burr recently?

Check if your red mark on the outer burr holder is at 5 o'clock. Also, check whether the outer burr holder tabs/flanges are broken.

If all of these look ok, inspect the adjustment ring, is there any give/wobble when you push it down at 7 o'clock and 3 o'clock. Preciso's adjustment ring are less hardy than the Virtuoso/Encore's because it is superglued on, instead of being snapped on.

HTH.

October 2nd, 2016, 11:55 am

Hi all,

Thanks for the reply, yes, I should have checked my grinder. I found that the 2 of the tabs of my outer burr is broken!

I believe that this is reason and also explains why my pour-over grind needs to be much more finer recent for a good extraction!

Looks like I need to spend money to get the outer burr replaced.

Kelvin

#5: Post by **dilin** » October 2nd, 2016, 9:00 pm

If you are in SG, CSH sells the outer burr holder for 10 bucks and you can change it yourself. No biggie.

#6: Post by **CoffeeBar** » October 3rd, 2016, 5:38 am

samuellaw178 wrote:Instead of focusing on extraction yield, the shot time/flow rate indicates the Preciso is not able to grind fine enough. You need to calibrate it to grind finer. There is a possibility the plastic collar is broken (coarse grind is a symptom) and needs replacing - this happens more often with hard dense light roasted beans.

kwongheng wrote:
Beans in = 20 g
Weight out around 40 g
Time = 19s

Insightful.

#7: Post by **CorvusDoug** » October 4th, 2016, 2:15 pm

Hey Kelvin,

I agree with trying to calibrate the burrs so they can grind a bit finer. If you want to get the shot sweeter/more extracted with the setup you have at the moment, just pull more out. Try 20g - 50g out (which should also draw out the time a bit). Sending more water through will extract more and get sweeter flavors, but it will also make the body more watery. This is just one of those compromises you have to make when your hands are tied. Hope that helps - good luck!