When we have had to much to drink up here in Maine, and forget to take the mackerel out of the cooler in August, and find them the weekend after..... 
.....We just let the good ole sun and fly's do the work for about a week, leave them out in the sun for a week and they should be fine.... 
Ya I've tried that, and as long as the towel is DRY you don't smell anything but right when it gets wet...BAMM!!! stink city!
Thanks everyone for the tips.
