Straying from my habits of never using non-wild yeast I made beer barm bread using a customer's fresh barm. The resulting bread contains brewer's yeast which I cannot call wild! The process remains same as with pure levain bread making and involves a preferment (i.e. a mix of flour, water and frothy barm) which is left to ferment for 24 hours before being added to the final dough ingredients (more flour, more water, grains/flakes,salt). Benefits of long fermentation remain: superior flavour (I think so myself!), keeping quality and (I have no scientific proof for it and this is based on my observation) lower GI.