Yes, because it has dijon mustard in it, you’ll need to store it in the refrigerator. I recommend a jam jar or mason jar with a lid to store your dressing. Keep it in the fridge, and take out a half hour or so before you want to use it. Olive oil has a tendency to solidify a bit in very cold refrigerators. When you’re ready to serve, just shake vigorously in the jar with the lid on to re-emulsify the dressing.