The "red" crema

[Sparky]

I heard this term bandied about on another site and it got me thinking. Some of my recent high points in espresso seemed to be crowned by a very rich deep brick red crema. In fact the day of the last bean bay pickup I had the opportunity to play on a La Marzocco FB70 with some of Brisbanes best baristi, and the espresso that issued was uniformly crowned with this deep red crema.

Unfortunately, if the beans aint good, even a deep red crema wont save them, but with a decent blend, the taste is sensational; with caramel/toffee/chocolate flavours very clearly defined.

As a comparison, the crema that I usually get from my machine is much lighter and more golden brown. I usually aimed for this extraction based on the extraction obtained with the same beans at the local cafe at work (which is owned by the local roaster).
However, after the play on the FB70, I went home and made a few shots, going progressively hotter and adjusting the grind finer until viola... red crema. Unfortunately the shot tasted a bit ashy... which incidentally matched the description/criticism given by the actual ex-roaster of these beans.

My hypothesis is that the red crema corresponds to caramelised sugars dominating the crema. Me thinks I need to investigate this further.

Any thoughts?

Cheers,

Mark.

[JavaB]

Re: The "red" crema

Mark

How hot did you have to go for the red crema to be produced? And what was the pour time (presumably longer than standard with a finer grind).....

Would love to get some myself!!

[Sparky]

Re: The "red" crema


Actually the term "red crema" was used on the HB site by a new owner of a La Cimbali Junior, as in "now I know how ot get the red crema" or something to that effect.

During the session on the FB70 I took a look at the grind they were using and it seemed finer than what I was using. Id guess somewhere between normal and ristretto pours. The temp on the FB70 was initially set to 93oC and was bumped up to 94oC later. The crema was invariably deep red for both settings, but the 93oC setting gave a slight grassy taste to one of the SOs being tasted. 94oC cured it. On my machine I just shortened the flush by 1 sec and went finer until I got the slower pour and the colour was very similar, which stopped me blaming the machine...

Cheers,

Mark.

[hazbean]

Re: The "red" crema

" ... going progressively hotter and adjusting the grind finer ..."

which of these do you think is the dominant factor in achieving
red crema?

have been experimenting with shorter cooling flush myself -- I
think for the better

[JavaB]

Re: The "red" crema

Well I just tried using Marks advice above......

About a 37 second pour (knocked the grind down a couple of numbers on the La Cimbali (0.04 mm smaller) and reduced the cooling flush by about 1 second.

Using Monsoon Malabar (which is roasted just to the start of the second crack) and the crema was richer in colour with definite reddish tinges at the start.... tasted pretty damn good as well.

Bit more experimentation and Ill get there! The elusive red crema 8-)

The other interesting thing- Malabar is normally a crema monster (at the normal settings) but set this way it produced significantly less crema.

[hazbean]

Re: The "red" crema

Thanks. As mentioned above, clearly tending towards a ristretto.

BTW do you measure time from the first drop appearing, or from
starting the shot? I always thought the former, but the good folks at HB
seem to think the latter. With a 5 to 8 sec pre-infusion, the diff is significant.

On another point:

" ... the 93oC setting gave a slight grassy taste to one of the SOs being tasted. 94oC cured it ... "

It so happened that I had pulled a shot earlier this evening from a two day
Yemeni roast, and observed slight grassiness. So out of curiosity repeated
the performance with greater temp (not measuring, but by reducing the
flush). Grassiness no longer apparent. Maybe I have to resurrect the TC
and calibrate the cooling flush. Oh well ...

[hazbean]

Re: The "red" crema

PS forgot to mention ...

I have occasionally over the last few months made a shot with a
noticeably red crema, but without being able to repeat it reliably.
In each case the pour was noticeably on the ristretto side (where I
like it), and the flavour superb.

[JavaB]

Re: The "red" crema

hazbean..

Yep Im in the HB school - time includes (in my case) about 5 sec pre infusion.

The higher temp and a more ristretto like pour does produce a superior espresso.... Just got to do a bit more experimentation.

[Sparky]

Re: The "red" crema


I believe the reference to red crema referrs to the colour of pours often reported on US/Canadian sites. I used to think that that sort of colour meant a burnt shot. That is until I tasted a few.

One observation was that red crema usually meant less crema. Hence the crema debate on another site. The arguement went something like: maximum crema = best taste, vs, best taste is not measured by crema volume.

Id like to hear what Luca has to add to this discussion, as hes had experience on both a Synesso and an LM FB80, which seem to dispense red crema at the flick of a switch.

[askthecoffeeguy]

Re: The "red" crema

Ive been getting some lovely red crema recently from a Ethiopian Sidamo based blend that Ive put together.

And I think it helps that Bazza the Bezzera has a lovely long slow extraction time, with approx 10sec of pre-infusion time, before the coffee begins to extract...

Yum!

Pat

[robusto]

Re: The "red" crema

I too find that redness is more likely to happen when a good many seconds have passed before the first drops tentatively make their debut from the spout.

With respect to timing: I always time from the instant the brew switch is pressed. Otherwise, if you go by actual extraction time, you can get into ridiculous situations where for the first 15 seconds nothing happens (grind too fine) and then it takes 50 seconds for 60 mls worth.

--Robusto

[askthecoffeeguy]

Re: The "red" crema

I start timing from when the coffee begins to extract which on my Bezzera is usually 10 after flicking the switch...

[Dimal]

Re: The "red" crema

Im with robusto on this one.... Always consider the stop-watch has started from the instant the brew switch is turned On. Mind you, I only time maybe one in every 15-20 shots to just ensure Im in the ballpark, all other shots are pulled on colour.

Mal.

[Thundergod]

Re: The "red" crema

Same here.
Hazel tells me a good shot might have an 8 sec delay before I see the first drops and that Im still looking for a 30 sec total.

[Wushoes]

Re: The "red" crema

You can always tell if youre in the ball park just by looking at it....doesnt hurt to check once in a while though