Just wanted to get some input from those who have done a sour mash. I am mainly interested in hearing how long some of your soured your mash for and the amount of sourness it imparted. I have had my mash going for ~15 hours and it is smelling sour. I am looking to add some twang to a wit style brew I am going to brew today or this weekend. The sour mash is about 16% of my total grain bill. Any thoughts?