Salt has such a rich history that it was once (and is perhaps still) a sign of wealth. In this latest installment of our series on flavor and taste, "Taste Buddies," Scientist-in-Residence Regina G. Barber goes on a salty flavor journey with scientist Julie Yu. Along the way, Julie explains salt's essential role in our daily lives and how it affects our perception of food. Follow Regina on Twitter @ScienceRegina. Email Short Wave at ShortWave@NPR.org.