First shot always slightly bitter - Page 2

Beginner and pro baristas share tips and tricks.
Eiern

#11: Post by Eiern » Aug 15, 2019, 12:50 pm

40g liquid in the cup means 59,8g water used for a 20g dose as some gets trapped in the puck (numbers from CoffeeTools)

So try a flush as long as would be used for your first cup. I'd rather throw away water than beans every day.

The group on my Classika PID was often running a little cold I think. Would maybe be a little more similar to your double boiler.

RNAV

#12: Post by RNAV » Aug 15, 2019, 10:53 pm

I, too, have a Synchronika and a Niche. In my research I ran across a very smart fella on this forum who did some temp stability testing on his Synchronika. Can't seem to find the thread now, but bottom line: a 5 sec warming flush was required to bring the group head up to temp. He recommended shot intervals around 90 sec between shots, if I recall correctly.

Anyways, based on that recommendation I've been doing 5 sec warm up flushes prior to the first shot since day one and can't say I've experienced first-shot-bitterness.

User avatar
lancealot

#13: Post by lancealot » Aug 15, 2019, 10:56 pm

Coffcarl wrote:Consider that it might not be the machine, but your pallette.
This.

I have read that in the first sips of espresso, the oils from the shot coat the tongue and make subsequent tastes of the same shot seem less bitter. A google search on the topic reveals several sources which may or may not be credible. One is a book titled Espresso Coffee: The Science of Quality by Illy and Viani (2005). It is mentioned in this text.

Though I do not remember where I first read about this phenomenon, I can say that when I was learning to dial in, I encountered this phenomenon myself and researched it. Now I make it a practice to cleanse my palate between shots when dialing in (if I am having trouble, or looking for a subtle or elusive flavor).

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Jake_G
Team HB

#14: Post by Jake_G » Aug 15, 2019, 11:20 pm

Dr. Joseph John actually has stated this, as well:
Josuma wrote:Its density, mouthfeel, viscosity, sur-
face tension and foam-forming abil-
ity are different from those of coffee
or coffee concentrate. The oils in real
espresso will coat one's taste buds and
inhibit the ability to detect bitterness.
Quote taken from "Crash Course in Coffee Science"

Cheers!

- Jake

Wattbe

#15: Post by Wattbe » Aug 18, 2019, 4:47 pm

Just a thought, but could it be old ground coffee (from the previous day) that's retained in the grinder?

I used to single dose with a Mazzer SJ and experienced a similar problem. I also noticed that the first shot of the day would run a little faster than subsequent shots too.
I discovered that, although I put 18gms in and got 18gms out, approximately 5 grams was old coffee that was stuck overnight.
To fix this, I'd put 4 grams of beans into the grinder to purge the old stuff out and then pour in my 18 gram dose ready to grind. The first shot problems disappeared after that.

If you have a true zero retention grinder then disregard all of the above!

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C-Antonio

#16: Post by C-Antonio » Aug 23, 2019, 8:12 am

When was the last time you took apart and cleaned the cam chamber and the drain valves?
Thats what sees the last drain water from the puck at the end of the day and the first water going into your new coffee the day after, what you taste might be in there. If it needs a good scrub then flushing helps but wont be enough to solve the problem.
“Eh sì sì sì…sembra facile (fare un buon caffè)!”

jjamesee

#17: Post by jjamesee » replying to C-Antonio » Aug 24, 2019, 10:52 am

I'm back after a few days of test shots, to answer some previous questions, I've been doing the pre-flush before every shot since the beginning, and before the first shot I put like 6g of beans in the Zero Niche and run them through the grinder.

To figure out whether it's a palette problem. I tried tasting the second shot followed by the first one and the difference was again noticeable, the first one was a bit more harsh and slightly bitter in comparison with the second one, which was clean and sweet. After that I decided to just start the day with sinking the first shot and that sorted out everything, except for the wasted beans:) So I figured it really must be the oils from previous day that cause this, does it not happen to you guys at all? I feel like I am the only one with this issue.
Never. This machine is only a few months old though. Is this supposed to be a part of a regular maintenance routine? As nobody has told me about that before.

Eiern

#18: Post by Eiern » Aug 24, 2019, 3:18 pm

Do you do a blindfilter backflush or two with water after each session? Do you beckflush with detergent every week or two?

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C-Antonio

#19: Post by C-Antonio » Aug 24, 2019, 8:03 pm

jjamesee wrote:Never. This machine is only a few months old though. Is this supposed to be a part of a regular maintenance routine? As nobody has told me about that before.
It is service so yes, not something you would do on a new machine but it also depends on how much you use it, how dirty it might get with the kind of use you do and your backflushing routine and so on. But keep in mind that I prefer to take apart and clean rather than send cleaners through the system much more often than other people.
You said that flushing the machine before the first shot helps but doesnt fix it so it makes me think there might be something there...
“Eh sì sì sì…sembra facile (fare un buon caffè)!”

jjamesee

#20: Post by jjamesee » Aug 25, 2019, 5:02 am

I backflush with detergent every 1-2 weeks and but normally I do not backflush with a blind filter, just a regular flush after each shot.