Steve asked the question about the impact of a pressurised coffee basket in his new coffee machine, and if he should change it to a after-market non-pressurised basket, improve his coffee.
Here is my reply.
Thanks for your email.
You have nailed it - the point that is letting you down is the pressurised basket. Let me first explain why some coffee machine manufacturers use presurised baskets in the first place, and the difference between non-pressurised coffee baskets.
A pressurised basket is different to a non pressurised basket by having only one single hole in the bottom of the basket, vs many holes in a normal basket. The idea is to force the coffee through the one tiny hole, and in the process, creating a fake crema. Thats perfect for the machine manufacturer, becasue even with stale supermarket beans, they can say "look how good the crema is from our machine", but it will lack taste - its just micro-foamed coffee.
Using fresh roasted beans will improve the flavour of your coffee, but the basket being pressurised means that you dont get any good feedback on what is really happening with your coffee extraction.
Breville make non pressurised baskets for their Cafe Roma boiler machine - the machine retails for about $80, but the spare bpart can be ordered seerately for under $10. if it fits your machine, thats what I reccomend as a solution.
When you pay more for a machine, really all you are getting other than facy looks, is a more stable and consistent tempreture and pressure, and better heatup times, which while important, is not absolutely necessary. You will get a much better benefit by changing your basket to a non pressurised basket, and using a coffee tamp. then you can experiment with technique to perfect your coffee.
your aiming for 30ml of coffee in the cup, over 25seconds. If you get more than 30ml, your grind is too coarse, or your tamp too light. I like to try and keep as many things consistent, ie;
30 ml of coffee (per shot)
7grams of coffee (per shot)
25 seconds extraction
15kg of tamp pressure (try using bathroom scales to get an idea of what 15kg of pressure feels like.
I also like to always use a double basket, per coffee extraction, into one cup (so 14g of coffee and 60ml).
Let me know how you get on.
Chief Espresso Officer
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