I formulated a beautiful lip/multi use balm using 45% organic unrefined mango butter 15% candelilla wax and the remaining % is oils. Everything has been perfect when making 1-3 jars, but I noticed my larger batches (10-15 jars) have turned grainy after about a month or so just sitting out in a room. I did already start selling these so I would prefer to not change my formula by adding any new ingredients, and would love some insight as to why this could be happening and how to remedy this.
My process is I add the mango butter and wax in a beaker that is put in a small saucepan with a couple inches of simmering/boiling water. I let the beaker sit until the wax and butter are melted (stirring to ensure everything is melted), I then add my oil mixture and stir until everything is mixed. I remove the beaker from the saucepan and stir for a bit before filling my jars. My sample jars that never turned grainy were always set out to cool at room temp, and I did the same for the larger batch, but they became grainy.
I've read about stirring until a trace forms before pouring, and putting the filled containers into the freezer for a bit to cool quickly, but how will I actually know if this remedies the problem without waiting months? I did an experiment with various cool down methods, but would appreciate some help understanding why this happened when I increased batch size and what I need to do to prevent this from happening in the future.