BUT WHAT DOES TEMPERATURE PROFILING MEAN?
While most high-end espresso machines allow you to set a precise brewing temperature, the RS1 also allows you to change the brew temperature up or down during the shot.
A large boiler at the back of the machine feeds water to a smaller boiler tucked inside the group head. If you want the water to cool down during your brew, it mixes cold water into the hot. On the other hand, if you want the water temperature to increase during the brew there is a tiny but powerful heating element to boost the temp.
WHY WOULD WE WANT A ‘TEMPERATURE PROFILE’ ANYWAY?
Well, if thermodynamics and laws of solubility are to be believed, extraction efficiencies are highly affected by temperature. Typically, but not always, the solubility (that is, the capacity of a material to be dissolved) of a chemical is increased as temperature increases. That said, some solubilities can decrease with increasing temperature… it can be complicated.
And for coffee, a mixture of hundreds of compounds, the impact of changing temperature on the resulting brew will be even more complex. But, thankfully, there is no better way of measuring changes in temperature on taste than by actually tasting the coffee.
And that’s what we did on my recent trip to Rancilio in Milan. We tested our Colombian – Las Acacias Estate & Formula 442 coffees, assessing flavour, sweetness & body.