To check a fabric to see if it is going to bleed I place a swatch in a microwavable dish. I cover the swatch with water and set the timer on high for one-two minutes. By using this method I found some fabrics that I planned to use did color the water so did not use them in my quilt. The fabric does not fray in the microwave but I don't know if it would determine shrinkage. Something I am going to check out.