Blonding

[JustinD]

Am I right in making the following statements:

"Early blonding can be due to the grind not being fine enought."

"Early blonding can be due to old beans"

Whilst I understand the first statement to be correct, can anyone support the second statement.
I ask this as some beans I have been using have been blonding early and I have made the grind such that any finer and the machine will choke. I have seen the second statement but I am unsure if it is correct. Appreciate any thoughts.

[javabeen]

Re: Blonding

Not sure that old beans will blonde early but they wont produce good crema. Old stale beans just wont give you a good extraction.

Poor distribution of grinds in the basket can also cause chanelling which leads to early blonding

Javabeen

[GregWormald]

Re: Blonding

Am I right in making the following statements:

"Early blonding can be due to the grind not being fine enought."

Actually, that is only ONE cause of early blonding--probably by channelling. Too fine a grind will extract early as well, so grinding finer is not necessarily a solution to early blonding.

Once the goodness is extracted the blonding starts. Really fine grounds extract in less water. Too coarse, and the coffee doesnt extract well at all and the result, while brown throughout the extraction is likely to be sour.

Greg

[JustinD]

Re: Blonding

thanks for responses. I dont think I have suffered chanelling but you never know. I have found, though, that some beans blond a lot earlier so I am trying to understand why.

[hazbean]

Re: Blonding

Recently Ive deliberately been letting some coffee get a bit older (up to three weeks) before finishing it. My impression (only an impression so far) is that sometimes they run a bit lighter as they age, which makes it more difficult to see the onset of blonding because there is less contrast. Disclaimer: the above may be complete nonsense.

[oneday]

Re: Blonding

my guess is that once roasted, the beans are oxidising, losing small but significant particles / solubles that would otherwise enter the cup if extracted within two weeks post roast. thus blonding results earlier in your older beans as there is less matter to be extracted (i.e. the coffee going stale)

to test this hypothesis you could purchase a tds meter or ExtractMojo and keep the dose and grind consistent. The hypothesis is supported by baristas who either finer grind or updose as time elapses since roast date.

i emphasise this is my subjective opinion, i may be wrong

[WSullivan]

Re: Blonding

to test this hypothesis you could purchase a tds meter or ExtractMojo

I am NEVER EVER going to purchase one of those!

;D ;D