What is an RDT?

RDT (Ross Droplet Technique) is the practice of adding a tiny amount of water to coffee beans before grinding.

The goal is simple: reduce static electricity during grinding.

Less static means:

• Fewer coffee grounds sticking inside your grinder.
• Less mess on your bench.
• More consistent coffee doses.

Despite the name, you're only adding one or two small droplets of wate, just enough to lightly coat the beans, not soak them.

Do I need to do it?

Not necessarily.

Some grinder manufactures recommended not using one for particular grinders. Some grinders produce very little static and don't benefit much from RDT. Others can make a noticeable mess, especially in dry climates or with lighter roasted coffees.

If you're constantly brushing coffee grounds off your bench after grinding, RDT is worth trying.

Home Coffee Lab Tip

A small spray bottle or dedicated RDT bottle makes the process quick and repeatable. One light spray is usually all that's needed.