Water, the weakest link in espresso brewing?

I recently disconnected my Everpure Claris water filter because of a my house renovation. This left me with a problem. Where could I find filtered and softened water for my espresso machine? Luckily my friend Frans Goddijn helped me out. He supplied me with bottled water that was filtered with his BWT Bestmax premium water filter.

After feeding the water to my espresso machine I noticed a significant improvement. There was a clear improvement of the cup quality of the espresso’s.

After that I decided not to reinstall the Everpure water filter. Instead of that I installed a DVA water softener. The water was softened but here was problem . It did not taste good. Cold from the tap you could clearly notice an off taste. I also brewed some too freshly roasted coffee with it and I noticed a clear salty taste. An explanation for this could be under extraction of the coffee. Also the coffee seemed to have more body and less fine delicate flavors. I also tested the DVA filtered water with different green tea’s. The tea’s were sweet but lacked delicate subtleties and character.

In audio terms I would say, it enhanced bass and mid tones, but there was a drop in the high frequencies.

After my tests it became clear, water has a big impact on brewing. Therefore I decided to buy exactly the same water filter as Frans. After installing the Bestmax water filter the taste of the espresso’s improved substantially. The flavor can be described as more open, more delicate, more character. Also the percentage of acceptable cups went up.

One final word. I’m not saying that Everpure Claris water filter is less good than the BWT Bestmax premium water filter. Less taste fidelity could have been the result of mistreatment or overuse of the water filter. I’m however not planning to switch back.

Tiny Cheap Fluid Bed Roaster update 8 Feb 2017

Tije de Jong made a first housing for the Tiny Cheap Fluid Bed Roaster. He also made a part that improves the movement of coffee beans inside the roast chamber. This improvement is not finished yet but it already makes a slightly larger batch size possible (310 vs 250 grams). Tije also made an addition to the chaff collector that prevents beans from escaping out of the roast chamber. Another advantage of this adjustment is that the roaster seems to need needs less fan adjustments during the roast.

Movie by Frans Goddijn.

Tiny cheap fluid bed: PID tuning

Yesterday we worked again on our Tiny Little fluid bed roaster. On the menu was to further configure the PID-settings. This should make it possible to precisely and consistently execute roast profiles.

For our test we used again Indian Cherry Robusta. This cheap coffee produced lot’s of chaff during the roast. Although the roast results looked fine we don’t recommend anyone to drink the as a single origin espresso. The bean however was perfect for testing purposes.

There were several things that we changed after our last PID-testing attempt. At first Frans brought along an active usb extension cable. This cable is supposed to make the communication between the TC4 board and the Artisan roast software more reliable. That means minimization of spikes or other reading errors. After examining all previous PID configuration attempts Frans suggested to start using the I value of the PID settings. This was a great idea because after that the PID worked magically good as you can see the graph below.

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