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Moist grapefruit sour cream cake made with fresh juice and zest. Bright citrus flavor, perfectly balanced sweetness, and topped with a simple grapefruit glaze.

If you love citrus desserts but want something a little more unique than lemon or orange, this grapefruit sour cream cake is such a treat. It’s bright, fresh, slightly tangy, and just a little bit bittersweet in the best way. The grapefruit really shines here. It cuts through the sweetness beautifully, while the sour cream makes the cake incredibly moist and rich. Every bite is soft, tender, and full of citrusy goodness with a delicate glaze that ties everything together.
Why You’ll Like This Recipe
- Perfect balance of flavors – Sweet, tangy, and slightly bitter from the grapefruit for a more complex taste
- Super moist texture – Thanks to the sour cream, this cake stays soft for days
- Easy to make – No mixer required, just a bowl and a whisk
- Not overly sweet – Great if you prefer desserts that aren’t cloying
- Freezer-friendly – Make ahead and enjoy anytime
Ingredients and Substitutions
- Grapefruit juice – I don’t recommend any substitution ere
- Grapefruit zest – Don’t skip this; it provides most of the citrus aroma. You can mix with orange zest for a milder bitterness
- Sugar – Regular granulated sugar works best, but you can reduce slightly if you prefer less sweetness
- Eggs – Use room temperature eggs for better emulsification
- Sour cream – Greek yogurt is a great substitute and gives a similar tang and moisture
- All-purpose flour – You can replace up to 25% with whole wheat flour for a slightly nuttier taste, but the cake will be denser
- Powdered sugar (glaze) – Can swap with a simple syrup glaze if you want a lighter finish
Tips for Success
- Don’t skip rubbing zest into sugar – This step intensifies the citrus flavor
- Avoid overmixing – Overmixing leads to a dense cake instead of tender crumb
- Use room temperature ingredients – Helps everything blend smoothly
- Check doneness properly – A slightly moist crumb is okay, but no wet batter
- Cool completely before glazing – Otherwise the glaze will melt and run off
Variations
- Grapefruit Orange Cake – Replace half the grapefruit juice with orange juice for a sweeter profile
- Grapefruit Lemon Twist – Add a bit of lemon zest for extra brightness
- Poppy Seed Version – Add 1–2 Tbsp poppy seeds for texture
- Bundt Cake Version – Bake in a small bundt pan; adjust baking time accordingly
- No Glaze Option – Dust with powdered sugar for a lighter finish
What to Serve This With
- A hot cup of coffee or tea
- Fresh berries on the side
- A dollop of whipped cream
- Greek yogurt, cream fraiche/sour cream for a tangy pairing
Storage & Reheating
- Room temperature – Store in an airtight container for up to 2–3 days
- Refrigerator – Keeps well for up to 5 days, but bring to room temp before serving
- Freezer – Wrap slices tightly and freeze for up to 1 month
- To thaw – Let sit at room temperature for a few hours
- Reheating – Warm briefly in the microwave (10–15 seconds) if desired
Frequently Asked Questions
- Is grapefruit cake bitter?
It has a slight bitterness, but it’s balanced by the sugar and richness from sour cream. - Can I make this ahead of time?
Yes! It actually tastes even better the next day as the flavors develop. - Can I reduce the sugar?
You can reduce maybe by 10-15%, but too much reduction may affect texture and moisture. - Why is my cake dense?
Most likely from overmixing the batter, adding too much flour, or you did not measure by weight. - Can I make this into muffins?
Yes, I’m not sure how many muffins you will get, but fill up about 3/4 full and bake at the same temperature for about 20–25 minutes or until a toothpick inserted into the center of the muffin comes out clean with a few moist crumb is fine.
This grapefruit sour cream cake is one of those recipes that feels a little special without being complicated. The citrus flavor is bright and refreshing, but not overpowering, and the texture stays beautifully moist for days. If you’re looking to switch things up from the usual lemon loaf, this is definitely worth trying—you might end up loving grapefruit in desserts even more than you expected.

Grapefruit Cake
Ingredients
Wet ingredients:
- 120 g grapefruit juice From 2 large grapefruits
- 2 Tbsp grapefruit zest
- 200 g sugar
- 150 g eggs from 3 large-size eggs
- 115 g sour cream
Dry ingredients:
- 240 g all-purpose flour
- ½ tsp baking soda
- ½ tsp baking powder
- ½ tsp salt
Glaze:
- 85 g powdered sugar
- 1 tsp grapefruit juice
- grapefruit zest
Instructions
- Preheat the oven to 350 F (180 C) for a conventional oven. Lower the temperature by 20 F (15 C).
- Grease a 9 x 5 inch loaf pan. Line with parchment paper on the long side, overhanging on the side

Prepare the cake batter:
- Rinse the grapefruits clean with water and pat dry. Zest the skin, be careful not to zest the white part of the skin because they are bitter. You will need about 1 Tbsp of zest for the cake and about 1 tsp for the glaze
- After zesting the fruit, cut it and start juicing. You will need 120 g of juice (1/2 cup) for the cake and reserve about 1 Tbsp (you may not use all) for the glaze
- In a mixing bowl, add 1 Tbsp of the zest to the sugar and rub it with your fingers for about 30 seconds or so. They would resemble wet sand


- To the same bowl, add 3 eggs, sour cream, and the juice. Whisk well until the mixture is emulsified

- Combine the all-purpose flour, baking soda, baking powder, and salt. Add this to the egg mixture and fold using a rubber spatula until just combined.

- As long as you don't see pockets of dry ingredients, you are done mixing. Do not overmix

- Scrape the batter into the prepared pan. Tap the pan on the counter a few times to pop any air bubbles and to even out the batter in the cake pan so the cake won't be lopsided later

Baking:
- Put this in the middle rack and bake for 65-70 minutes. Start checking at 65 minutes. A cake tester inserted into the center of the cake should come out clean, with a bit of sticky crumb is fine as long as it's not wet

- Set the pan on a cooling rack. Let the cake cool in a pan for 5 minutes. Then use an offset spatula to loosen the cake and then carefully lift it out of the pan and put it on a cooling rack to let it cool down completely. The cake needs to be cooled down completely before glazing
Glaze the cake:
- Only prepare the glaze when you are ready to glaze them as they set pretty quickly. Combine the powdered sugar with 1 tsp of reserved grapefruit juice you set aside earlier. If it's too thick, you can add a bit more of the juice to thin it out. Spread the glaze on top of the cake. The glaze will set in few minutes

To serve:
- The cake is very moist and stays moist for days if kept in an air-tight container.
How to store:
- They can be kept at room temperature for 2-3 days. For longer storage, this cake also freezes very well. Wrap few slices together in a cling wrap and put in a freezer bag, push all the air out and seal the bag. They can be kept frozen for 1 month. Simply thaw at room temperature for few hours before serving.









