Does preinfusion time affect the timing of a shot?

[ezralimm]

Simple, dumb question really. Sorry if this has been asked before, a quick search did not turn up any answers.

I start a shot by pressing a button on the EM6910.

Then the pump pulses before going all out.

Do i count the time the pump pulses as part of the extraction?


This is important as the difference between a 24s shot and a 28s shot is quite big, and a "28s" shot with 4s preinfusion may be really similar to a proper 24s shot.

I know that on my machine, shots under 25s tend to be watery and an ideal target is closer to 28s. Is this because of the preinfusion time coming into play?

Then again, preinfusion = brewing (? right?).

Confused. Some clarification would be appreciated. Im trying to record a series of videos on youtube and I need to fix the definition of pour time for consistency.

[acoggins]

Re: Does preinfusion time affect the timing of a shot?

Ask 5 people and youll get 5 different answers.

My answer is it doesnt matter as long as youre consistent in your timing and are happy with the result in the cup. But yes, preinfusion is brewing in my books.

[A_M]

Re: Does preinfusion time affect the timing of a shot?

Ask 5 people and youll get 5 different answers.

My answer is it doesnt matter as long as youre consistent in your timing and are happy with the result in the cup. But yes, preinfusion is brewing in my books.

Yes

and


Yes

[beanflying]

Re: Does preinfusion time affect the timing of a shot?

I need to fix the definition of pour time for consistency.

There is no definitive answer to this other than the generally acepted norm of 25-30 seconds for the shot. However some beans and machine combinations work better at longer than that.

As to pre infusion that is a can of worms that varies from bean to bean and machine to machine and user to user so trying to define "normal" is a waste of time. On my Izzo lever I have settled on 7-8 seconds with Genovese beans but with a few of my home roasts I was using about 10 seconds.

Personally I dont count the pre infusion time as part of the shot.

Trying to make espresso a by the numbers exact science thing is a waste of time and effort as it is a feel, taste and finese thing when you get past the basics. So call what ever you are doing a "guide" (it is not chemistry more alchemy) or put it as try from x to y time and taste it to see what is better in the cup.

[Wine_of_the_Bean]

Re: Does preinfusion time affect the timing of a shot?

Once water hits the coffee, the brewing process has begun.

[barrel]

Re: Does preinfusion time affect the timing of a shot?

I am not so worried about when the process starts as when it ends. When it starts blonding I stop. If the volume is right anywhere from 22ish to 30ish seconds depending on the bean that works for me.

[brett230873]

Re: Does preinfusion time affect the timing of a shot?

A coffee aficionado I was talking to recently was getting wonderful shots out of his Rancilio S20 that were taking 40 seconds!!! Take every rule as a starting point and with a grain of salt. How does it taste??? If great, then youre doing it right. Forget Smellivision and bring on Tastevision..., only then youll have 10 000 different palates give you 10 000 different summaries. And I wont be subscribing because I personally dont want to taste the majority of what the Interweb has to offer!!!!! Great question though...

[acoggins]

Re: Does preinfusion time affect the timing of a shot?

Every machine is different. The Mirage I work with has a huge preinfusion chamber. The other day I pulled an insanely slow double ristretto for a customer (and then one for myself) that lasted over 60 seconds. The result was awesome. Lots of body and choc sweetness, though no clarity.

Try that on a home machine and youll end up with a burnt ashy cup.

[blanyon]

Re: Does preinfusion time affect the timing of a shot?

Think you might be confused with pre-infusion as the 6910 doesnt have it. I think you are just talking about the time it takes from when you hit the button to when the coffee starts to come out which (in my books) is not pre infusion.

I define pre-infusion as low(er) pressure water being applied to the coffee puck for a few seconds (varies) before the full 9 bars (or whatever pressure you choose) is applied and brewing truly starts. You can have mechanical or electronic pre-infusion I believe but I am not really up with the mechanisms.

[ezralimm]

Re: Does preinfusion time affect the timing of a shot?

Looks like it really depends on who I ask. For consistency, I will be including 4s preinfusion in my videos for shot timing, but I will also note that 4s went to preinfusion.



"The 6910 uses a form of pre-infusion by pulsing the pump for a few seconds before running continuously." - http://www.coffeetamper.com.au/**/reviews/sunbeam-silvia/

Its probably not true blue preinfusion, but it seems to do the job. Two pulses of water is enough to saturate the grounds.

[Thundergod]

Re: Does preinfusion time affect the timing of a shot?

Think you might be confused with pre-infusion as the 6910 doesnt have it. I think you are just talking about the time it takes from when you hit the button to when the coffee starts to come out

I think youll find Sunbeam says it has.
Page 26 of the Instruction Book:

Pre-Infusion

11. Once an espresso operation has been
activated, before the espresso pour starts
the pre-infusion feature will release three
short bursts of gradually increasing water
pressure onto the coffee cake. After this,
the full water pressure is applied to the
coffee cake

Personally I think the term "pre-infusion" is a misnomer.
Technically, pre-infusion would be the time before the water hits the coffee.

[blanyon]

Re: Does preinfusion time affect the timing of a shot?

I stand corrected!

[WSullivan]

Re: Does preinfusion time affect the timing of a shot?

From what ive seen(not a 6910 expert by any means), the pre-infusion doesnt spit out very much water at all without the pf on(just so you can see the amount of water), i cant see it being overly effective, are you able to get rid of the pre-infusion on a 6910, or are you only able to shorten it..... it would be interesting for some blind(and deaf) taste comparisons :-?

[beanflying]

Re: Does preinfusion time affect the timing of a shot?

Bit like peeing on a bushfire I reckon the 6910, my old Solis had a similar system. Anyone ever stopped a 6910 after this spitting to see how dry most of the puck actually is? My guess is it is only the top layer of the puck that is moist.

Preinfusion in the case of my levers is full boiler pressure and a full shot of water sitting on top of the puck and screen. Normally if the grind, tamp and dose is right then as soon as the lever gets kicked up the first drops come out of the PF so the puck must be close to or fully saturated.

[ezralimm]

Re: Does preinfusion time affect the timing of a shot?

Measured with digital scale: 10g of water from three short bursts of the pump./\/


That is interesting, as while it is enough water to dampen the grounds (they expand abit and create a better seal, especially around the edges), it is not nearly enough water to have the thermal inertia necessary to heat the grounds up and start the brewing process.