I ususally wash untill the water is clean about 3-4 times, depends on your ratio of trim:butter. With my 4x batches which is 4oz to a lb of butter, it takes about5-6 times. I always just put the butter in mason jars then into a double boiler, if you have about a lb of trim to process, doing it my way will take about the entire day, the biggest wait time is waiting for the butter to re solidfy. Also the color of the butter melted is much darker but, dont worry just keep washing till the water inside the jar does not stink or have a brownish tinge to it. Just like when growing cooking good edibles takes time and patience.