Facts about pistachio shells

Pistachio shells used to be red. Many of you won't remember this, but eating pistachios used to mean that you ended up with hands that were stained red.

So what's the story here? Well, before 1979, the U.S. imported the majority of its pistachios from the Middle East. When the pistachios were harvested, they weren't immediately dried and this caused water stains to appear on the shells. These stains were thought to be unappealing, so the nuts were dyed red to cover the stains. 

In 1979, the U.S. placed an embargo on Iranian pistachios, which gave U.S. pistachio growers a chance to get in on the market.  The U.S. growers used a different harvesting process, which resulted in the pistachios being dried right away. No water stains meant no dye needed. 

So there you have it. The first food fact that you never knew you wanted to know.