Ooops, let me correct myself. I should have never said no resource. That statement was shown to be in error.
A blogger suggests coffee is served too hot and a mechanical engineer has a publication suggesting it is served too hot based on scald potential.
A recent survey shows...
As far as 170-175, I have to agree there or even slightly cooler is where coffee may be by the time it touches someones lips. Add in creamer and it could be even colder. Also ice could be added.
But I believe the topic on point is Hot Coffee without all the fluff and the National Coffee Association and the Specialty Coffee Association of America (SCAA) both suggest serving temperatures in excess of 170F. So I'll change my statement from "no resource", to no major acknowledged association who deals exclusively in coffee suggests it be served at any less than 170F.