Mustard and grapefruit did not immediately hit me as a killer fish marinade. But my chef friend Ted, visiting us in Florida from Seattle, insisted it would be great, especially since we had a supply of fresh grapefruit from the tree in my mom’s yard.
When we hit the Star Fish Co. in the historic fishing village of Cortez, we settled on a a heavy clear-eye bluefish. “Are you sure? Have you ever had bluefish?” the guy behind the counter said. Fair enough. Bluefish is sort of the “dark meat” in the fish world, with a slightly oily and stronger flavor than most fish, particularly if they’re not fresh. (Random fact: they are the only fish known to kill for the sake of killing, rather than just survival.)
Back at home, Ted slapped on a marinade of mustard and grapefruit juice. Sounds weird, but honestly, the result was awesome. It muted the flavor into a softer one, almost like a whitefish. Best part? The whole fish cost $8 and we got two enormous fillets. One fillet was dinner for three people, the other one went into the freezer for another night. We rounded it out with wild rice risotto and arugula dressed with just lemon juice, olive oil, salt and pepper. Good, and healthy.
Fish with grapefruit and mustard
It was designed with blue fish in mind, but certainly this could work for any fish, including salmon or whitefish. Peel the grapefruit, then section it over a bowl to capture the juice that inevitably results from this process. We didn’t use salt as we felt the scant salt from the mustard provided enough. Add a little only if you must. If you’re new to grilling fish, check out this article.
1 1/2 lb. fish fillet(s) of your choice
1 whole grapefruit, sectioned
2 tablespoons Dijon mustard
2 cloves, minced
2 tablespoons olive oil
Many cranks of black pepper
3 green onions (as garnish)
Grapefruit sections (as a garnish)
Put the fish into a shallow, flat pan or bowl. Peel and section the grapefruit, capturing the juice. Set the sections aside. Mix the juice with the mustard, olive oil and minced garlic. Smooth over the flesh of the fish. Crank a generous coating of black pepper on the top. Cover with plastic wrap, refrigerate and let marinade for at least a half hour and up to four hours.
Prepare a barbecue grill. When the coals are ready, place the fish directly on the grill. If you filet has skin on it, put it side down. Cover and cook. Generally, it takes about eight minutes for an inch-thick fillet. Estimate your fish thickness, check it after an appropriate number of minutes and touch it in the middle. If it’s firm to the touch, it’s done. Our bluefish fillet was about 1 1/3 inches thick and took about 12 minutes.
Lift the fish off the grill carefully, nudging a spatula along the bottom of the fillet between the flesh and the skin. If done right, the skin will be left on the grill. Garnish with green onions and reserved grapefruit portions. Serve while it’s hot.
Originally published in 2009. It has been updated.