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by Barbara
(Australia)
I do feel for you dear quilter. I see you have tried all things but there is another remedy I have heard that might be worth a try. I have never had the occasion to use it so far, but I have become a bit slack in pre-washing fabric I have to confess.
Cover the affected stained area with NATURAL YOGURT and leave for 'a while' - whatever it takes I guess - before rinsing out.
Good luck and I will check again one day to see if you have had any success with this idea.