What is blonding and why is it bad?

[NewToEspresso]

Another newbie question...

[christretto]

Re: What is blonding and why is it bad?

Blonding is the stage at when the coffee extraction starts to change colour from a dark brown reddish colour to a pale yellow colour.

To find out why it is bad simply do the following.

Pull a 30ml extraction but split it into 3 cups as it is being extracted. ie 10ml in each from the spouts. Start by tasting the first cup, then the second, and finally taste the last cup.

You will find out why blonding is bad.

[marcstolk]

Re: What is blonding and why is it bad?

Blonding = Yuck!

[recurve_boy]

Re: What is blonding and why is it bad?

There is also a change in the consistency of the coffee. It gets visibly more watery. Ive been looking out for this rather than the colour change as some blends Ive tried dont have a noticeably blond colour.

[tempestv8]

Re: What is blonding and why is it bad?


Yes, Im finding it hard to see when its actually blonding, as the colour change is rather gradual for me. Its not like it suddenly gets markedly lighter in colour when all the crema is extracted.

Could this be due to my tamping technique that the blonding is not obvious to me?

[Dimal]

Re: What is blonding and why is it bad?

Gday tV8,

Wouldnt think so mate, probably more to do with the coffee youre using Id say...

Mal.

[tempestv8]

Re: What is blonding and why is it bad?


Hi Mal,

Maybe Im going colour blind! :-)

I do see that if I switch from one bean to another, the colour of the crema can be substantially different.

These days I just try to pull more ristrettos instead of the full 30 ml extraction when making coffee for guests.

And since they are asking for a 2nd cup soon after the first one, I know it cant have been too shabby.

Lawrance

[Dimal]

Re: What is blonding and why is it bad?

Ahh,

No worries mate, pretty difficult to get a blonde shot when pulling ristrettos 8-).... your guests are very discriminating imbibers too I must say,

Mal.

[reubster]

Re: What is blonding and why is it bad?

Yeppers, I too sometimes find it hard to determing blonding via colour alone.

If the beans produce a high crema, the extraction can be relatively blond all the way through, but if you go long enough [hopefully over 25 sec] you can see the transition from foamy to watery extraction. ....does that sound right?

Also, I watch the entry point of the flow onto the top of the crema, if the point of entry is lighter than the creama, then its time to stop.

[NewToEspresso]

Re: What is blonding and why is it bad?

Yeppers, I too sometimes find it hard to determing blonding via colour alone.

If the beans produce a high crema, the extraction can be relatively blond all the way through, but if you go long enough [hopefully over 25 sec] you can see the transition from foamy to watery extraction. ....does that sound right?

Also, I watch the entry point of the flow onto the top of the crema, if the point of entry is lighter than the creama, then its time to stop.

This blonding thing has got me worried lately because Im using fresh beans from Venezianos and the shot comes up "blonde" quite early but most of it is crema. After the 20+ second mark the shot starts to get diluted, unlike the thick oily crema that flows into the glass. For a moment there, i thought I was getting blonding early. Despite that, the end result is better coffee than Ive had anywhere so even if it really was the case where its blonding early, Im still happy enough with my latte to not change too much. But it looks like its the crema thats giving the colour of the shot the blonde look. The amount of crema from fresh beans as opposed to those I got before (in exposed sacks) and the shot time is unbelievable. I didnt think freshness of the beans actually made that much of a difference but now I know it does!!

[Dimal]

Re: What is blonding and why is it bad?

Gday NTE,

Theres some great info about this and many other topics to be found on the Home Barista website, their forum is a mine of info too with links to videos and How Tos, etc. Try this page to start off with and then scout around a bit,

Cheers,
Mal.

[reubster]

Re: What is blonding and why is it bad?

NTE

I too use blends from Veneziano, mainly their Estate.
In my experience, it tends to produce a very heavy crema [virtually 95% of the pour] . It has a tan/blondish colour throughout the pour and the colour change is less distinguishable than the dilution.
If you look close at the extraction you should see whats called "tiger striping" [dark lines] within the foam.
As said earlier blonding is really about the transition from extracting the good oils [and flavour] to the extraction of of purely bitter caffiene.

Kill the shot at the onset of dilution.
You should also try espressos from first pour and compare them to what you make at home.

[marcstolk]

Re: What is blonding and why is it bad?

I find when underdosing, the shot goes blond quite fast..but updosing gives a nice long dark pour.. all things being equal of course

[>Veneziano]

Re: What is blonding and why is it bad?

Hi All,

Marcstolk hit the nail on the head; a greater dose for the same pour time will delay the onset of blonding. This means that you might need to coarsen up your grind (and is one of the reasons why I cant stand stepped grinders!)

A nice little exercise to work out what blonding is is to pull your cup out from under the stream, rather than stopping it, and just watch and see what happens.

Light coloured crema can sometimes be due to low brew temperatures. Veneziano Estate is roasted and blended to be brewed in the low 90 range ... I think that Im at 92C or 93C at work. If youre buying Estate from First Pour, youre more than welcome to have a look at how the shots are flowing to get a feel for what we are after.

Cheers,

Luca

[richy_4000]

Re: What is blonding and why is it bad?

Yeah, home barista.com is a fabulous site. When I was first getting into coffee I came accross this site and was blown away by the depth of knowledge needed to be a competent barrista. Reading all that you begin to realise how complex a beast espresso is, and come to terms with the inexplicability of the fact that you cant get decent espresso at most cafes, even with their expensive machines.

And yeah, theres plaenty on blonding there too. Also check out http://www.coffeeresearch.org/espresso/potential.htm

Richy