In our office we have a bean-to-cup machine. The rate at which we use it means we always have fresh beans - generally it tastes pretty good for machine-made coffee. However, first thing in the morning, just after turning it on, the first few coffees can taste very acidic indeed. Is there any potential remedy for this other than throwing away the first few coffees?
My thought is that once you turn on the machine, the machine starts to heat the water. Often the heating system is regulated by a PID regulation (Maybe on-off regulation). The machine will heat the water fast to make sure you can get your cup of coffee:) Once the water is heated it will stabilize to the intended temperature. If the water is heated above the intended temperature it will cause acidic compounds to be extracted from the beans. After a while the temperature is stabilized and you will experience that the coffee is no longer acidic.
Another theory is that the pipes within the machine are not clean.
You can test both.
Try turning on the machine an hour before making the first cup. If this helps it is probably a temperature issue.
If not try to clean the machine by running through hot water before making the first cup.
Hope one of these solutions will help you with your issue.
"Life is too short for bad coffee"