Grapefruit Poppy Seed Loaf Cake

5 from 1 vote

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Using both the citrus zest and juice in the batter and icing, makes this grapefruit poppy seed loaf cake, an easy quick bread recipe, incredibly fragrant and full of flavor.

Grapefruit Poppy Seed Loaf Cake

Quick breads blur the boundaries between breakfast, dessert and snack.

They are a universal treat that make sense at lots of different times during the day. I think that’s why I love them so much.

Baked in a loaf pan, quick breads can be casual and spontaneous or they can be dressed up for something more formal.

Banana bread is my go-to loaf, but I’ve been so inspired by winter citrus lately, that I thought it was okay to skip the bananas.

Even if it was just this time.

Grapefruit Poppy Seed Loaf Cake

I had a serious debate about what kind of citrus to use.

Poppy seeds were an absolute must, but I didn’t want to default to lemon. Of course you can’t beat that classic combo, but I craved a twist.

Grapefruit ended up being my chosen citrus. I’m a bit late to the party on this softball sized fruit. Now I can’t get enough of its tart flavor. 

Grapefruit Poppy Seed Loaf Cake

How To Make A Grapefruit Poppy Seed Loaf Cake

To start, I combined the dry ingredients. Then to flavor this grapefruit poppy seed loaf cake, I rubbed the zest into granulated sugar. My hands smelled absolutely amazing!

I beat the eggs, vegetable oil and vanilla extract into the fragrant sugar, and then combined the wet and dry ingredients alternating with Greek yogurt.

The yogurt gave the loaf a moist, tender crumb with a sublet tang. 

Before transferring the batter to the pan, I folded in poppy seeds and grapefruit juice. I even brushed the top of the loaf with more juice while it was hot from the oven. 

Once the loaf cooled, I whisked together grapefruit juice and confectioners’ sugar to make icing.

I glazed the loaf and sprinkled on poppy seeds. It took about a half hour for the icing to set, and finally the loaf was ready to slice.

Each bite had the fresh flavor of grapefruit. Next time if I am looking for more crunch, I will be more generous with the poppy seeds.

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Grapefruit Poppy Seed Loaf Cake

5 from 1 vote
Prep: 20 minutes
Cook: 1 hour
Cooling Time: 2 hours
Total: 3 hours 20 minutes
Servings: 10
Using both the citrus zest and juice in the batter and icing, makes this grapefruit poppy seed loaf cake, an easy quick bread recipe, incredibly fragrant and full of flavor.


  • Non-stick cooking spray
  • 1-1/2 cups all-purpose flour
  • 2 teaspoons baking powder
  • 3/4 teaspoon kosher salt
  • 1 grapefruit zest and juice
  • 1 cup granulated sugar
  • 2 large eggs at room temperature
  • 1/3 cup vegetable oil
  • 1 teaspoon vanilla extract
  • 3/4 cup plain Greek yogurt
  • 1 tablespoon poppy seeds plus more for decorating loaf
  • 1/2 cup confectioners’ sugar


  • Preheat the oven to 350 degrees. Grease an 8-1/2-inch by 4-inch loaf pan with non-stick cooking spray and line with parchment paper.
  • In a medium bowl, combine the flour, baking powder and salt. In a large bowl, rub the grapefruit zest into the granulated sugar until it is very fragrant.
  • Use an electric mixer on high speed to beat in the eggs, oil and vanilla until pale and thick, about 4 minutes. On low speed, add half the dry ingredients followed by the Greek yogurt and 5 tablespoons grapefruit juice. Fold in the remaining dry ingredients and poppy seeds. Transfer the batter to the prepared baking pan, smoothing into an even layer.
  • Bake the loaf until golden brown and a toothpick inserted into the center comes out clean, about 50-60 minutes. Poke the top of the loaf and brush with 3 tablespoons grapefruit juice. Cool in the pan for 15 minutes and then transfer the loaf to a wire rack to cool completely.
  • In a small bowl, whisk together the confectioners’ sugar with 1 tablespoon grapefruit juice. Drizzle the icing over the loaf and sprinkle with poppy seeds. Let the icing set for 30 minutes before serving.
  • Store in an airtight container.


Adapted from Bon Appetit March 2016


Calories: 248kcal | Carbohydrates: 44g | Protein: 5g | Fat: 9g | Saturated Fat: 1g | Polyunsaturated Fat: 5g | Monounsaturated Fat: 2g | Trans Fat: 0.1g | Cholesterol: 33mg | Sodium: 278mg | Potassium: 96mg | Fiber: 1g | Sugar: 22g | Vitamin A: 343IU | Vitamin C: 8mg | Calcium: 90mg | Iron: 1mg

Nutrition information is automatically calculated, so should only be used as an approximation.

Additional Info

Course: Quick Breads & Muffins
Cuisine: American
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Hi, I'm Paige.

Welcome to Last Ingredient where you will find simple seasonal recipes with plenty of fruits and vegetables, all for the home cook.

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Recipe Rating

1 Comment

  1. 5 stars
    Delicious loaf cake! I had some beautiful pink grapefruit to use up and this was the perfect recipe. It’s a keeper.