MediumRoastSteam question: why is the temperature so low, in the lower eighties Celsius? I always though the water temp hitting the puck should be between 91 and 95, depending on the coffee type and roast level.
So, the profile Jake is using is an unusual one called ‘Extractamundo Dos!’, which is a high-flow, high-extracting turboshot.
In general, with fast-extracting profiles, a high proportion of the extraction happens early
In the shot. This in turn means that a lot of the solubles will have been removed from the puck relatively quickly, which lowers the puck viscosity. The rapid reduction in viscosity increases the risk of channelling, and therefore the risk of extracting astringent compounds. Secondary to this, Joe (the guy who designed the profile) found the shots tasted best at a lower temperature.
A more ‘standard’ profile would absolutely try to maintain a puck temperature closer to 88’C as you suggested. I think the confusion her is because this is quite a niche profile to use!
Remember the DE1 is unusual as it measures actual temperature in the coffee slurry, not at the boiler. It monitors and dynamically adjusts the water temperature going to the puck in order to maintain this temperature. A typical boiler temperature of 93’C is set this high as it is trying to compensate for the huge drop in temperature of the water when it mixes with room-temperature coffee. One of the things I like about the DE1 is the temperature you see on screen is the actual temperature of the coffee, not the boiler or the group head.
This is why there is often a small ‘dip’ at the start of the graph, as it displaying the room-temperature coffee coming up to temperature by mixing with hotter water coming from the pumps (this water will likely be at a temperature of around 93-95’C initially, but will reduce as the temperature of the coffee rises).
That’s a rough and ready, non-expert explanation of my understanding of why temperatures are often seen as being lower on the DE1 than other machines. The actual temperature at the coffee is actually going to be very similar, it’s just being more accurately recorded, and done so at a different place to most machines.
Hope that helps!
