Additives will enhance the look, feel and scent of your soap bars. Using additives such as Coffee Beans will color the soap to a rich brown coffee color. Of course you will want to grind these beans to a granule size of your choice. It will give the soap a wonderful coffee bean scent and it'll exfoliate and clean the dirtiest gardener's hands you've ever seen.
Experiment with grinding coffee beans either course or fine. Some soap makers will use the spent coffee grounds from their coffee makers. Hey, why waste fresh coffee beans!
Whether fresh, spent, course or fine coffee beans, you'll want to add a very small percentage of these additives (usually under 3% of the total oil amount for your soap batch).
Add these coffee grounds to the soap mixture during "trace". This is the step in the soap making process where the soap begins to thicken-up similar to gravy.