Top 5 Grinders for Light Roast Espresso Application - Page 10

Grinders are one of the keys to exceptional espresso. Discuss them here.
User avatar
Denis

Postby Denis » Feb 12, 2019, 4:50 pm

You are pulling 20% EY average shots on the monolith conical. Your coffee is far from light roasts, sorry to say but light starts at 90 agtron, your beans are 71, that is like an espresso roast. The beans are to inflated to be roasted light, you can post some pictures.

Because you are limited with none or less preinfusion you tend to under extract in the 1:2 ratio. A lot more remains inside the coffee puck and that is shown by the 1:3 ratio that lowers the strength but adds more EY%, because there is more to offer left there.

I bet with a longer preinfusion using the same coffee and the same grinder you could pull easily 22% in a 1:2 ratio.

Use an IMS or a VST basket with 20g coffee, this will end in less channeling and more even shots. The VST 17g basket I have but its not plain straight on the walls at the base of is basket. The 20g VST I find it better and less channeling, easier to work with.

If that is the coffee you are using and you like that is great, and I am happy that woks for you. My advice would be to not be tempted to go into big expensive flats because you won't obtain better tasting shots using a different grinder. The sweet spot for those kinds of roasts are where you are 19-22 EY. Adding more EY and going rampage on 70 sec shots will just bring out the darkness out of those beans.

We went to big flat grinders to find a solution for really light roasts, that could not offer any good result on normal grinders.

Here is a picture of a light roast, it is a bit exaggerated but just to be clear. I respect and won't debate other choices about drinking dark-medium-light roasts.


Image

User avatar
cafemolino

Postby cafemolino » Feb 12, 2019, 5:13 pm

nuketopia wrote:So I did some readings this morning with the VST refractometer.

I'm finishing off a bag of Counter Culture Apollo, 100% Worka Ethiopa, roast date 1/22/19. The roaster says it is agtron 71, but I cannot confirm this, as the contents of "Apollo" rotates through the year. It is a "light" roast, but not as light as scandivian roasts I've pulled in the past.

The coffee was pulled on a Linea Mini with Strada 17g basket, (more or less a LM branded VST style basket). Pressure 9.0 bar, temperature 93c (199.5f). Water is my formulated mineralized blend at about 80 TDS. (find my thread on it elsewhere).

Grinder is the monolith conical, adjusted as needed to produce beverage weight in desired time. Starting point is 29.5 out in 30 seconds, as measured with an Acaia Lunar scale.

Dose is as weighed in basket.

I use the VST recommended process to measure TDS. VST recommends drawing the sample into a syringe, attaching a VST filter and pressure filtering the sample, then allowing it cool to room temperature. Further, I calibrate the VST with distilled water between each sample.

Filtering is controversial. VST recommends filtering, and it results in lower TDS readings. Some notable persons recommend skip it, and there are threads on it. However, I find it to be useful for consistent readings and can be used to compare various brewing methods.

Unfiltered refractometer measurements are higher than filtered.

I measured two of my typical morning espressos and then did 3 more with different parameters to see how the extraction proceeded. I also tasted each hot, partially cooled (recommended) and well cooled to room temperature of about 68f.


Data and calculated value table:

<image>


My preference is for the smaller shots with TDS around 10% with this coffee. It is denser and the flavors are very good, nicely balanced with EY ranging from 17.5% - 18%.

All the shots were good though, none exhibited over-extracted flavors. Had slight channeling on the 36g dose. The very long shot of 54g (~1:3) was very fruity and juicy, with no bitterness or harsh flavors and lots of clarity. However, I don't particularly care for the body at the density it produced. It ran for 38 seconds.

So honestly, with the Monolith Conical, the LMLM and a light roast ethiopian, I was able to pull over 22.24% E.Y. with good results and no particular effort on my part, other than just dialing the grinder a little bit.



Nice job (same parameters same machine 9 bars, water etc.) thanks a lot,

just one question did you measure room temp. VST gives different results with different temps.

nuketopia

Postby nuketopia » Feb 12, 2019, 5:27 pm

Room temperature is 69F.

Aguirre

Postby Aguirre » Feb 12, 2019, 5:31 pm

Denis wrote:Use an IMS or a VST basket with 20g coffee, this will end in less channeling and more even shots. The VST 17g basket I have but its not plain straight on the walls at the base of is basket. The 20g VST I find it better and less channeling, easier to work with.


Totally agree with this one. From my collection of baskets, the VST 20g is the one-size-fits-all favorite.

@Larry (nuketopia): I don't have a refractometer. Will be buying one in the near future. While this doesn't happen, would you be open for running another round of readings in case I mail you a bag (yes - FREE coffee) of my own roasted beans? They do fit the description of "light" we're talking about here, and it would be great to have that comparison for the sake of community enlightenment. In case you're up to it, send me a PM and we talk about the details.

nuketopia

Postby nuketopia » Feb 12, 2019, 6:26 pm

One of the problems is that none of us so far, actually have an Agtron chip to compare to.

Most of the references I'm aware of show the SCAA Gourmet Agtron scale to describe the following:

95: Cinnamon (Arabic)

85-75: Light Brown (Scandinavian)

65-75: Brown (American)

50-45: Dark Brown (City and Full City)

40-35: Brown-Black, slightly oily, (Italian and Vienna)

There are more than one Agtron scales for coffee, this would be the "gourmet" version.

Also, even though these are taken with the same lighting and background, it is really impossible to assure the iPhone X camera is locked into a particular white balance and saturation

Here is a speciality medium espresso roast:


Image


Here is the one I was pulling this morning:
Image

User avatar
Denis

Postby Denis » Feb 13, 2019, 1:55 am

The first one is a fire hazard roast. Typical blend with robusta almost Italian style roasts.

The second one is a nice espresso roast with all the beans cracked and developed, your setup is perfect for this kind of roasts. Glad you enjoy it.

erik82

Postby erik82 » Feb 13, 2019, 2:23 am

Denis wrote:Real feedback is a device that takes away unwanted forces from the coffee puck when it tells you to. Optimization on extraction, a thing that a manual lever or a pump machine cannot do precisely, approximately yes for some it is enough.


I'd say this isn't true. My Strietman CT1 can easily do 1:3 ratio's and with the Manometer from Gabor I can do every kind of pressure profiling very precisely. In the Strietman I can feel what the puck and flow is doing which you can't do on an automatic machine as you can only watch and react when it's in fact already to late because the feeling needed to adjust comes before the visual signs.

User avatar
cafemolino

Postby cafemolino » Feb 13, 2019, 7:48 am

Denis wrote:The first one is a fire hazard roast. Typical blend with robusta almost Italian style roasts.

The second one is a nice espresso roast with all the beans cracked and developed, your setup is perfect for this kind of roasts. Glad you enjoy it.


your judgement fire hazard.....

by the way Etzinger says the new Etzmax are made for light roast any experience and TDS (but needs standard TDS, not long PI's, 9 bars machine etc), that is a conical grinder and very fast

devlin2427

Postby devlin2427 » Feb 13, 2019, 8:15 am

If the coffee in the first picture was sold as specialty, I would change the supplier.

The ETZ max is a beefed up Sette 270 and should more or less what a Sette does with light roasts.

User avatar
Denis

Postby Denis » Feb 13, 2019, 8:33 am

Seems like people like to hear nice stories.

ETZ Max did a burr named "light" that can be used for lights roasts. But that name doesn't have anything to do with TDS/EY or the distribution. With light beans their grinder did choke and could not grind. So they did a variation of burrs that doesn't allot a lot of beans to enter the burrs to block it, so less stress for the grinder and everyone is happy.

ETZ has a lot of plastic parts inside the grinder. The grinder is well made on the exterior (no plastic like on the Sette) but some pieces on the burr carrier are plastic.

The picture showing 3 burrs the one on the left is the "light " burr.

It remains a good grinder, does single dose great, but it remains a conical, that will never be among the best for light roasts, because you will end with low TDS/EY, underextracted shots.

Image
Image
Image
Image