Quick answer: This tuna rice bowl has about 32 grams of protein and 345 calories per serving, and takes about 35 minutes, mostly a quick marinade for the egg. A soft-boiled egg soaks briefly in a soy-mirin marinade — ajitama-style, the ramen-shop egg — then sits over tuna and rice. Serves 4. Sodium runs moderate-to-high, about 585 mg per serving.
Where the other rice bowls in this collection use raw or plain canned tuna, this one puts the egg in the spotlight — a soft, jammy yolk marinated just long enough to pick up flavor without curing all the way through.
Why This Recipe Has About 32 Grams of Protein
| Source | Per serving |
| Canned tuna, drained (110 g) | 21.3 g |
| Egg, 1 large (50 g) | 6.3 g |
| Cooked rice (120 g) | 3.2 g |
| Everything else | 0.8 g |
| Total | 31.6 g |
The marinated egg does real protein work here, not just flavor — a meaningful step up from a plain garnish egg.
A Note on Sodium
About 585 mg per serving, roughly 25% of the WHO’s 2,300 mg daily limit — in line with the other rice bowls now that the marinade uses low-sodium soy sauce, the same choice made across the rest of this collection.
- Soy marinade (low-sodium soy sauce): ~247 mg
- Canned tuna: ~275 mg
- Egg: ~62 mg
- Everything else: ~1 mg
What helps: a shorter marinade time with a lighter soy pour keeps this from climbing higher — a full soy soak, as some ajitama recipes call for, would push this considerably.
What You Need
Makes 4 servings
- 4 cans (5 oz / 142 g each) light tuna in water, drained (about 440 g drained total)
- 4 eggs
- 2 tbsp low-sodium soy sauce
- 2 tbsp mirin
- 1 tbsp water
- 4 cups cooked rice (480 g)
- Sliced green onion, sesame seeds and nori strips, to serve

How to Make It
- Soft-boil the eggs, 6-6½ minutes, then cool immediately in ice water and peel carefully.
- Marinate: combine low-sodium soy sauce, mirin and water in a small container, add the peeled eggs, and let sit 20-30 minutes, turning once.
- Cook the rice, if not already made.
- Assemble: rice, tuna, and the halved marinated egg on top.
- Finish with green onion, sesame seeds and nori.
Tips
6 to 6½ minutes exactly is what gets a jammy, still-soft yolk. A few seconds longer and it sets too firm to be worth marinating.
Peel gently under running water. Soft-boiled eggs tear more easily than fully hard-boiled ones.
Substitutions
Mirin: a pinch of sugar dissolved in the soy-water mix works as a substitute.
Storage
Marinated eggs keep 2 days refrigerated in their marinade, though the yolk firms up slightly the longer they sit.

Tuna Egg Rice Bowl
Ingredients
Method
- Soft-boil the eggs 6-6½ minutes, cool in ice water, and peel.
- Marinate in low-sodium soy sauce, mirin and water for 20-30 minutes.
- Cook or reheat the rice.
- Assemble rice, tuna and halved marinated egg.
- Top with green onion, sesame seeds and nori.
Notes
- A shorter marinade keeps the sodium lower.
- Eggs keep 2 days refrigerated in their marinade.
Nutrition
Per serving (recipe makes 4):
| Calories | 345 |
| Protein | 32 g |
| Sodium | 585 mg |
Verified against the Tuna nutrition workbook, calculated ingredient-by-ingredient from USDA FoodData Central reference values.
Frequently Asked Questions
What is ajitama?
A Japanese soft-boiled egg marinated in a soy-mirin mixture, most commonly seen as a ramen topping — jammy yolk, lightly seasoned white.
Can I marinate the eggs longer?
Yes, up to 2 days, though the yolk firms up progressively and the flavor gets saltier the longer it sits.
What if I overcook the egg past soft-boiled?
It still works, just loses the jammy-yolk texture this recipe is built around.
Can I make the eggs ahead?
Yes — they’re one of the few components here that actually benefits from being made a day ahead.
More High Protein Tuna Recipes
Part of the 🍚 Tuna Rice Bowls collection, alongside Korean Tuna Rice Bowl.
Made this? Leave a rating and a comment below.