Blonding problem

[talbashan]

Hi all,
I roast my own coffee, have a Rocky and a BZ99.
Generally the coffee is alright, but no always amazing. my main problem is that even when it initially comes out picture perfect, ie honey like colour and consistency with tiger stripes, that ends quite soon and i then get a pale blonde colour for the remainder of the pour. The puck has a light impression of the screw in it (i believe thats a good thing).

I always over dose, straighten/flatten with my finger tap and tamp.

any suggestions?

[TC]

Re: Blonding problem

Hi all,
I roast my own coffee, have a Rocky and a BZ99.
Generally the coffee is alright, but no always amazing. my main problem is that even when it initially comes out picture perfect, ie honey like colour and consistency with tiger stripes, that ends quite soon and i then get a pale blonde colour for the remainder of the pour. The puck has a light impression of the screw in it (i believe thats a good thing).

I always over dose, straighten/flatten with my finger tap and tamp.

any suggestions?

It can be the coffee, the operator, temperature and a host of other factors.

I suggest that you get hold of a p/f pressure gauge if possible and check that your over pressure valve is adjusted to no more than about 9.5 bar....

Chris

[pie_in_ear]

Re: Blonding problem

What is the age of your coffee and how are you roasting it? If your coffee is too fresh it can cause early blonding. Also have a look for any signs of channeling in the spent puck. At what point does it start to blonde? Does it blonde gradually or all at once? When troubleshooting Id suggest to try the simple things first.

[talbashan]

Re: Blonding problem

hi again,

thanks for this advice. when i bought the BZ99 (second hand), i put in for a service and was told that the pressure is ok.
when i roast my beans i usually allow about 24 hrs before drinking. do you think thats enough?
the blonding seems to come out at a particular point. the puck itself looks solid and good with a light impression of the screw.
the coffees themselves are not bad, just not that god shot taste (which could also be my roasting..).
thanks,
Tal

[pie_in_ear]

Re: Blonding problem

Tal, Id try you beans around the 7 day mark. Or better still, roast enough to try them everyday over a 2 week period. Then you will get a good idea of how they change with age. When the beans are too fresh and still degassing violently the oils within the bean have not had time come to the surface (not on the surface but near the surface). This can produce early blonding.