Replies to This Discussion

Permalink Reply by Christopher Zimmerman on March 12, 2010 at 7:40pm

Ok... lets see if i can explain this properly...

so say the basket you are using is a double... if you dose 14g as opposed to 16g, using the same coffee of course, since we don't want bean density to come into play yet, you have less coffee in the portafilter... and thus it can spread out more making more room for water to flow through...

think of a room, for this example lets say a 20ftX20ft room... put 30 people in the room and walk from one side to the other... then put 40 people in the room and do the same thing... you will generally find it harder to walk through the 40 person room... so it will take you longer to get through the 40 person room...

going back inside the portafilter we can use this comparison to see that a higher dose results in a slower shot since it is harder for the water to get through... a slower shot results in a smaller volume... likewise when you lower the dose it is easier for the water to get through and thus the shot is faster and has a higher volume...

if you can, pick up a copy of the professional barista handbook by scott rao, it has some great explanations and diagrams that helped me a lot in understanding the reactions that occur...

hope this helps... cheers

Daniel Williamson said:

something I've come across in my experimenting and talking with other baristas, is this: when I down dose, it seems like I pull longer shots; and conversely, when I dose higher, the shot seems shorter (volume-wise, of course).

Does anyone else (1) agree with this observation or (2) know the reason why that seems to be the case?

It's nice to pull out those different flavors, and sometimes I switch it up based on my mood. I don't necessarily care about the final volume (as taste rules supreme), it's just an enigma to me because it seems logical that the opposite would be true. I mean, if there's more coffee, I should be able to pull more oils and flavor out (translating into more volume), but the facts state the opposite is true.

• ▶ Reply

Permalink Reply by Daniel Williamson on March 13, 2010 at 1:58pm

Thanks, Chris! That makes more sense to me.

• ▶ Reply

Permalink Reply by Cody Gordon on March 22, 2010 at 6:28pm

yea, chris made a lot of sense.

at our shop we use four barrel coffee and it does have certain parameters that you can usually get from your roaster. in our case we pull 19-20 gram shots in a time frame in the mid 20's for a 1.5 ounce shot. these are guidelines, but definitely not set in stone rules. coffee acts different given the weather, humidity etc...

as soon as you put more coffee into the portafilter it is going to take longer for the water to flow through. more coffee equals a longer shot. a finer grind equals a longer shot. less coffee means less mass to go through, thus a faster shot. a more coarse grind equals a faster shot. coffee will always take the path of least resistance. that is why if you have an unlevel tamp the channeling over extracts one area of your coffee puck, making it stringent.

ask your roaster for general guidelines and experiment.

the final judge for your coffee should be your palette.

Daniel Williamson said:

Thanks, Chris! That makes more sense to me.

• ▶ Reply

▶ Reply to Discussion

• ‹ Previous
• 1
• 2
• 3
• Next ›
• Page