I did some research and would suggest layering the quilts with newspaper for a few days. That will absorb some of the odor.
The odor is caused by mold spores.There are three things you can try. Add a cup of white vinegar to the wash water and another cup to the rinse water then air dry, preferably in the sun.
You could add a cup of baking soda to the wash water.If you use vinegar and baking soda together, they neutralize each other.
Or you can wash with detergent as usual but add a cup of ammonia to the rinse water.
Never use bleach and ammonia together as they create toxic fumes when mixed.
With all methods, drying in the sunshine is suggested.Once the quilts are dry if any odor remains, laying them in the grass can help. The chlorophyll in the grass is a great odor remover.
Good luck!!