The shell of the pistachio is naturally a beige color, but it may be dyed red or green in commercial pistachios. Originally, dye was applied to hide stains on the shells caused when the nuts were picked by hand.[51] In the 21st century, most pistachios are harvested by machine and the shells remain unstained.[51]
Wikipedia
Well now I’m wondering what those stains were. Did they dye them red because the people picking them had their hands bleeding? We were all just ingesting small amounts of laborer’s blood?
The shell of the pistachio is naturally a beige color, but it may be dyed red or green in commercial pistachios. Originally, dye was applied to hide stains on the shells caused when the nuts were picked by hand.[51] In the 21st century, most pistachios are harvested by machine and the shells remain unstained.[51] Wikipedia
Well now I’m wondering what those stains were. Did they dye them red because the people picking them had their hands bleeding? We were all just ingesting small amounts of laborer’s blood?
Another commenter said it was the oil on people’s hands
Blood oxidizes to a dark brown/black pretty quickly so a red dye wouldn’t really hide it.