Hey all. I have brewed what I call a black ale that is very similar to a robust porter using about 8.3% special roast. After a month in the bottle, there is a slight whisky and raisin like character that is present. It almost takes like it was barrel aged or something. Although this characteristic isn't bad it also isn't what I intended.
After looking at the description for special roast, it includes sour and tangy so I assume it is coming from that.
Has anyone else experienced this when using special roast? Also, would brown malt be an acceptable sub to get rid of this flavor but keep some of the biscuit/nutty notes?