Oh, I wrongly assumed you were commenting on the 4.7. "Just round it up to 5 ABV for Christ's sake."
In the same vein, back when I first took up the hobby, I thought the darker the cigar wrapper the stronger the smoke.
To produce a stout/porter the barley is roasted. That's it.
This process has nothing to do with fermentation.
Primary fermentation is yeast & sugar. Other cereal ingredients also add a small kick to the overall ABV.
If the barley is roasted that makes less food for the fungus to digest and convert into alcohol.
All things being equal, to make a stronger stout/porter you have to add more yeast and sugar to the recipe.
Guinness Draught is just barely over 4 ABV.
In the same vein, back when I first took up the hobby, I thought the darker the cigar wrapper the stronger the smoke.
To produce a stout/porter the barley is roasted. That's it.
This process has nothing to do with fermentation.
Primary fermentation is yeast & sugar. Other cereal ingredients also add a small kick to the overall ABV.
If the barley is roasted that makes less food for the fungus to digest and convert into alcohol.
All things being equal, to make a stronger stout/porter you have to add more yeast and sugar to the recipe.
Guinness Draught is just barely over 4 ABV.