For the most part, sushi's staple ingredients -- fresh fish, seaweed, rice and herbs -- are gluten-free. Some additions do contain gluten, however. Plus a few ingredients that are supposed to be gluten-free, like fresh fish, can become contaminated with gluten. So even if you're positive that your favorite sushi roll doesn't have any components that contain gluten, let your server know that you can't have gluten as soon as you order.
Imitation Crabmeat Details
Imitation crabmeat is a processed form of surimi fish. It's an inexpensive form of seafood that is manufactured to taste just like crabmeat. The problem is that to get that crab texture and flavor, manufacturers add in wheat gluten or wheat flour. Gluten protein from wheat is the least expensive way to get the right texture in imitation crabmeat while making a product that is shelf-stable. When you order crab sushi, verify that it's made with real crabmeat, not the imitation stuff.
Rice is a grain, but it's not related to barley, rye or wheat, so typically you can have it on a gluten-free diet. You need to be aware of where your rice comes from, though. Because it's a crop, it's possible for other nearby grains to blow over onto the rice fields. If you're making sushi at home, read the label on the package of rice to verify that it's gluten-free. If you don't see "gluten-free," "free of gluten," "without gluten" or "no gluten" on the label, it's possible that your rice has trace amounts of gluten. When you go out to eat, ask the chef if the rice they use is gluten-free. Any rice that is labeled "gluten-free" mustn't have more than 20 parts per million of gluten, according to the U.S. Food and Drug Administration.
Gluten in Added Ingredients
Just as you were careful to alert the kitchen about your gluten sensitivity, be careful with dipping sauces. Soy sauce does contain gluten, so you'll have to ask for a type that is gluten-free. Wasabi is generally free of gluten, but it could become contaminated with gluten in the processing plant or have coloring agents that have gluten. Lastly, certain spices or flavoring ingredients could add a little gluten to your sushi entree. Cooks may add these seasonings to rice, sprinkle them directly onto the fish or stir them into dipping sauces. Read the food label or ask the chef to be certain.
Gluten can stick to gluten-free sushi if the surface is contaminated. For example, if a chef drops a handful of wheat ramen noodles into boiling water, then touches the cutting board and the fish for your sushi, your dish can wind up with gluten. This is why it's critical to inform anyone preparing your food about your dietary needs. They'll need to change gloves and sanitize any cooking surfaces before handling your food.
- Academy of Nutrition and Dietetics: Avoiding Gluten Cross-Contamination
- U.S. Food and Drug Administration: A Glimpse at 'Gluten-Free' Food Labeling
- Celiac.com: How to Safely Order Gluten-Free Sushi
- Samba Steak and Sushi House: Gluten Free Menu
- Jackson Siegelbaum Gastroenterology: Gluten-Free Diet
- Surimi and Surimi Seafood, Second Edition; Jae W. Park