Why Exactly Is Mustard So Yellow?

A condiment enjoyed by hot dog lovers, pretzel enthusiasts, and Kendrick Lamar alike, you can always rely on mustard to bring some zing and funk to whatever you're eating. You can add mustard to tacos, or you can roast fish in mustard like Ina Garten. If you're feeling adventurous, you can even dip your watermelon in mustard (although you may want to use non-yellow varieties for that). While there are some brands we like more than others, as you can see in our worst-to-best ranking of yellow mustards, it's hard to go too wrong with the yellow stuff.

Which raises the question: Why, exactly, is yellow mustard so yellow? The condiment is made from ground mustard seeds, which range from white to brown to black in color — a far cry from the end result, which is as yellow as the lines on the highway. So where does this golden hue come from? Well, it actually comes from a very different spice: not mustard, but turmeric. Once the two ground elements are combined with water and vinegar, you get that familiar yellow color.

While the color of the mustard seeds does affect the color of the finished product, to an extent — brown mustard is made from brown seeds, for example — the result is never naturally that sharp shade of yellow. For instance, Dijon mustard is made from brown and black seeds mixed with white wine, so the resulting color is a dark golden brown. German mustard is made with brown seeds, while English mustard (such as Colman's) is made with brown and white seeds. Yellow mustard, on the other hand, is made solely with white seeds — so the color has to come from somewhere else.

So why do mustard manufacturers turn to turmeric, an earthy, somewhat bitter spice often used in curries, to boost the hue? Turmeric has been used as a natural dye for hundreds of years, and it plays nicely with the bright, acidic flavor of mustard. In fact, it can even be used as a mustard seed substitute in a pinch. And so when the two are used in harmony, we get the tangy yellow marvel we know and love. 

The spice itself is incredibly versatile. As well as mustard, other foods can also get a colorful boost from turmeric, from non-dairy cheese or butter to yellow cake. It's also the golden spice your chicken noodle soup craves.