I'm wondering if it's the microwave way of melting the butters that give you problems? I use unrefined shea in my lotions sticks, lip balms and just yesterday for my whipped shea. I never microwave it and I never have grainy problems. I never measure to 170 degrees. What I do is fill a sauce pan with water about 1/4 of the way. Set a larger stainless steel bowl on top, not down in the water, put the shea in by itself, turn the heat on med to med low and let it gradually melt down before adding anything else. Takes about 20 minutes for this to happen. Its right around this time that I have to turn the heat down so the water isn't bubbling too much. Then I add my other butters, beeswax if making stick or balms. It takes longer doing it this way, but I never have to worry about it being grainy. HTH