Reading this thread and this thread in its original location, I have not been able to find whether the fertilizer in the yeast nutient, 20-0-0, is supposed to be nitrate or sulfate based.
The reason I wonder is I made some pugirum and it has an off-flavor in it. The off-flavor is a bit like rotten eggs (hydrogen sulfide). I used 21-0-0 ammonium sulfate. It is my understanding that the fertilzer is there for nitrogen content. Ammonium sulfate is also 24% sulfur as sulfate. Could this be the source of the off-flavor? I followed the rest of the wash recipe very closely.
This is the first iteration so I had no rum oils to add, and I used 50% low wines + 50% wash in the spirit run instead of dunder, as recommended by Punkin (in the thread over there).
I have to admit that these are my first attemps with a pot still, so maybe I am not making my cuts right. My experience with the way heads and tails smell/feel come from running a VM column.
I am tempted to put a themometer well in the high spot of the lyne arm to see what the vapor temperatures are. I am measuring abv with a 100mL volumetric flask, thermometer, tripple beam balance and a conversion spreadsheet. (Parrot building is on my to-do list).
Any thoughts on ammonium sulfate causing off-flavors?