Grinds

[HKomet]

Hi,

I'd need some theory about grinding coffee beans, being unsure how fine the grind should be. I heard that the ideal extraction time for an espresso (ristretto) should be around 25 seconds. If longer, then tamp it less or grind the beans coarser, if shorter, tamp it more strongly or make the grind finer.
Here's what I notice: sometimes, even though I'm using the same grind, the result will vary, giving me overflow or overextraction. At other times, the coffee flows out beautifully but then tastes surprisingly bitter. When that happens I almost always observe grounds at the bottom of my cup.
I'd like to make the most of my coffee, so what do I do wrong? Should I grind it differently on rainy days? I'd appreciate your inputs.

 

[Randy G.]

Too many variables to discuss specifics, but if you have a stepless grinder, it is generally best to skip tamping rituals. Tamp the same way every time. It is more important to have an accurate dose - that is, the exact same amount of coffee every time. For that you need a gram scale capable of weighing to .1 grams. After that, you need to work on distribution before tamping. Getting the coffee as perfectly and evenly distributed throughout the basket.

A good tool is a bottomless portafilter. That is a portafilter with the entire bottom cut off (no spouts). During the extraction you can see whether the extraction is going evenly, or if there are areas that are under extracted, or if yo have channeling causing sprites. It is instant feedback if the pre-extraction ritual went well or not.

Without knowing your equipment (which is not in your profile nor mentioned in your post0 it is difficult to say what you should try beyond those general tips above. But as long as you are tamping evenly (straight down) any other tamping ritual is over-rated or is compensating for other problems that should be addressed.

 

[HKomet]

I've got this kind of machine (Faema E61)
premium-kaffee.ch/images/produktbilder/zubehoer/vitudurumv4.jpg[/url]

and a Mazzer mini grinder.

I use 10 grams for a coffee and rarely do the 720° tamp thing. But I'll try a bottomless portafilter, definitely. Thanks for the reply

 

[Randy G.]

That is a nice machine. You are pulling single shots? Noirmally a double will be about 16 grams. I never weighed a single as I never pull singles.
These can be difficult and narrow the margin of error.
Check this article on my website on making espresso: http://www.frcndigital.com/coffee/HowToEspresso.html]1212 - EASY GUIDE TO BETTER ESPRESSO AT HOME
Since the problem is inconsistent, I would guess that it is caused by either inconsistent dose (using slightly different amounts of coffee each time), or from distribution inconsistencies in the basket.

 

[HKomet]

Yes that's right, I only do single shots. I guess I can say it's due to inconsistent dosing as I weighed 50 in a row and the discrepancy was minimal. Thanks for the link and help.

 

[janbaars]

I find this a helpful resource...

( I want to put in a link, but i'm not allowed yet. hihi!

ineedcoffee . com coffeegrind

 

[Randy G.]

Yes that's right, I only do single shots. I guess I can say it's due to inconsistent dosing as I weighed 50 in a row and the discrepancy was minimal.

It depends on the scale. If you are using a scale that weighs in whole grams, these round up (or down) to the nearest gram, so you have a +/- 0.5 gram range. That means that you could be off by +/- 5%, so for any two given shots, you could have a difference of close to 10%.

But, when some shots pull fast and turn blondes too soon, the is a sign of poor distribution before tamping. Additionally, when pulling singles, the margin of error is much less than doubles - accurate dose, distribution and grind are much more critical.

 

[HKomet]

No actually I meant it cannot be inconsistent dosing. I don't know what's wrong with me, it must be the 15th mistake I make in my posts. The scale I have is very accurate (weighs in centigrams).

Thank you all for your help.

 

[alphawave7]

I spent quite a few years with Mazzer Mini's, and the doser model throws hard from right to left, giving uneven distrubution in the PF (favors left side buildup). To remedy this, I used the yogurt cup modification to reduce errant throw, and WDT technique to redistribute the grind evenly before tamp. Only then did I achieve consistent, quality pulls...and as suggested above, double baskets (I prefer triple, actually) are more forgiving for these issues. I wouldn't even attempt single basket pulls, myself.

edit: If you have the means ($) I'd upgrade the grinder to a Super Jolly...that Faema would produce even better shots with it, noticeably superior to the Mini.

 

[HKomet]

I spent quite a few years with Mazzer Mini's, and the doser model throws hard from right to left, giving uneven distrubution in the PF (favors left side buildup). To remedy this, I used the yogurt cup modification to reduce errant throw, and WDT technique to redistribute the grind evenly before tamp. Only then did I achieve consistent, quality pulls...and as suggested above, double baskets (I prefer triple, actually) are more forgiving for these issues. I wouldn't even attempt single basket pulls, myself.

edit: If you have the means ($) I'd upgrade the grinder to a Super Jolly...that Faema would produce even better shots with it, noticeably superior to the Mini.

Thanks for the tips. Could you tell me more about that WDT technique? By the way I have the electronic Mini grinder. In what way would the Super Jolly be superior to that?

 

[alphawave7]

Ah! The electronic Mini has the 64mm burrset like the SJ, but I thought you had the regular Mini, which has the 58mm burrset..and yes, you CAN taste the difference! You probably also have the doserless, so no paddle-knocking and poor PF filling. WRT the WDT technique, this article should resolve the mystery:
Improve your Espresso with Weiss Distribution Technique • Home-Barista.com
Give this method a try, and see if your consistency and shots improve.

 

[Randy G.]

WDT = Weiss Distribution Technique"
It involves using a thin tool (like a dissecting needle) to stir the grounds in the portafilter basket before leveling (if necessary) and then tamping. SOme use a yoghurt cup, cut down (no bottom) to fit over the basket to hold the grounds in place. This action breaks up clumps and redistributes the coffee.

Do you NEED to do this? It depends on the output from your grinder, the humidity in the room, and more. It is one reason why I like a doser (and my grinder). I can dose while and I have removed the PF forks from my grinder. I move the PF around and dose while grinding. I rarely get any clumps at all, so my distribution is almost done when the grinding is finished. I then use the "Stockfleths Move" (easier for you to watch a few videos than for me to explain it).

 

[alphawave7]

Another for WDT

And one for 'Chacago Chop'

 

[HKomet]

Thank you once more for the videos and the advice.