In a perfect world ..... we would all have time to take perfect care of our beloved quilts. We would fill our perfectly clean bathtubs with lukewarn water and soak our quilt in a very mild detergent. We would continue to wash the quilt by hand, then rinse it twice in soft water. Air drying, laid flat in the perfect temperature with a slight breeze ( not in direct sunlight, of course) might work best. The quilt might then be displayed over a quilt rack or wrapped in acid free tissue paper and stored in a temperature controlled environment.
In the real world ..... or at the very least in my world, things get washed in the washing machine and dried in the dryer!!! I barely have time to do the laundry much less to do it by hand. Our quilts are used on our beds, tossed on the couch, cuddle in on the recliner and carried in the car for the long ride home. We love our quilts, we use our quilts and occasionally ( like this morning ) we get a little schmutz ( today it was syrup from my grandson's waffles! ) on our quilts. I have, however, found a great product to wash my quilts in. I use a soap called Orvus. Orvus is a paste soap made by Procter and Gamble. It is very gentle. It contains no phosphates and gets out most problems ( including syrup ).
I discovered Orvus when I was given a bag containing a partially constructed quilt top that was being held together with steel pins. It had been stored in a damp basement and had many marks on it, including a few spots beginning to mold and it smelled musty. I completed the quilt top, quilted it and added the binding. I then washed the finished quilt in Orvus soap and much to my delight the stains and most of the rust marks from the pins were gone after just one washing!!! Orvus soap truely saved this quilt. I have been using Orvus ever since.
Once in a while I have seen Orvus packaged in an eight ounce container labeled "Quilt Soap". I have occasionally found it in quilt shops or in quilt magazines. It works so well I am surprised I don't see it all over the place. I do know if you go to a farm store, feed store or tractor store you can buy a large container for a very reasonable price and you will discover many uses for it.
I hope you will give this stuff a try. It will help you keep your quilts clean and smelling great!