Last week I shared some basic science about espresso equilibrium temperature. This week I’ve whipped up a calculator that can figure it all out for you. Put in your recipe and check out the result!
Because the specific heat of water is so much higher, it will affect the equilibrium temperature much more than coffee can. Feel free to play around with the numbers to get a feel for the effects of water vs coffee temperature.
If you can measure the temperature of your coffee grinds pre- and mid-service you’ll be able to see the difference. You can also use this calculator to find a brewing water temperature that achieves the same overall equilibrium temperature. It won’t make an espresso identical to the cooler grinds/hotter water during pre-service, but it’ll definitely be closer!
I highly recommend an infrared thermometer as coffee grinds are very poor thermal conductors when measured with thermocouples.