http://intheinterestofannie.blogspot.com/2011/03/tempering-butter-101shea-mango-and.html
Tempering Butter 101(shea, mango, and cocoa)
Although I am in love with lotion bars and lip balm, I felt that mine were turning out slightly grainy. It isn't something that completely ruins the products, for as soon as they warm up the graininess goes away and it melts into your skin, but I have not been entirely happy with them. I learned that the culprit is my butters. This has nothing to do with the quality of the butters, but more that the fluctuation in temperature causes the butters to crystallize. The best way to get rid of the graininess is to temper the butters. Maintaining a high heat for a prolonged amount of time causes the crystals to melt completely, resulting in smooth butter (hopefully). Each butter has a slightly different process, so I will share a little on each one.
Shea Butter: Heat to 170 - 185 degrees. Maintain this temperature for approximately 15-30 minutes.
Mango Butter: Heat slowly to 100 degrees. Maintain this temperature for 45-60 minutes.
Cocoa Butter: Heat slowly to 100 degrees. Maintain this temperature for 45-60 minutes.
Slowly melt the butter, lifting the thermometer
out and away from the pot occasionally to
get an accurate temperature.
The most difficult part of this process is maintaining the temperature. I heated my butters in a pot on my gas stove on low and stirred and watched until it was melted, all the while constantly watching the temperature. With the shea butter, I slowly raised the temperature until I reached the desired 175, then eased it back down. The mango and cocoa butter, in order to maintain 100 degrees, I had to alternately turn the burner on and off as the temperature climbed and decreased (usually in about 10 minute intervals). It was kind of a long, tedious process, but I hope it will be worth it when I have nice, smooth lotion bars.
I have also reformulated my lotion bars, adding mango and vitamin E to create a more moisturizing bar that has more "slip" on the skin.