Tuesday 8 March 2016

Japanese Purple Sweet Potato Bun

I have tried baking purple sweet potato buns a few times, but using local purple sweet potatoes. This round I used the Okinawa, Japan, purple sweet potatoes. Personally, I find the colour of the Japanese sweet potato is more intense, and would not turn brown after steaming. It has a smoother texture and sweeter aroma.

The sweet buns, as expected, are soft yet a bit springy. Nice to eat it plain :)

Yield: 9 buns in a 20cm sq pan
Breadmaker: Whirlpool BM 1000
Bread weight: 400 g
Raw dough: about 429 g

35g cold trim coconut milk
65g cold fresh milk
30g raw sugar
1/4 tsp salt

20g beaten egg
20g unsalted butter

80g purple sweet potato paste
180g bread flour
3/4 tsp instant dry yeast

Some bread flour for sprinkling 

1. Line a 20cm square pan with parchment paper. Set aside.

2. Steamed about 100g of peeled purple sweet potato chunks with pandan leaf (optional) in medium high heat for 20 minuets, or till a thin skewer can poke through easily.

3. Remove the pandan leaves. While the sweet potato is still hot, mash it using a fork. Collect 80g of sweet potato paste.

4. Pour cold trim coconut milk and cold fresh milk into a container and keep in the fridge for about 20 to 30 minutes minutes.
You can do this step while waiting for the sweet potato to be steamed.

5. Pour the milk mixture and beaten egg into the bread pan.

6. Pour in the sugar and salt.

7. Add in the unsalted butter.

8. Loosen the sweet potato paste slightly and add into the bread pan.

9. Pour in the bread flour.

10. Dig a hole with your finger and pour in the instant dry yeast.

11. Place the bread pan back to the bread machine.

12. Close the lid and select "Dough" function, and start the process.

13. When the program stops, let the dough continue to sit in the pan for another 15 minutes.

15 minutes later, the dough is ready.

14. Turn out the dough onto a floured surface. Flatten it with your palm to release the trapped air.

15. Divide the dough into 9 equal portions, about 47g each.

16. Roll up the small dough, pull down the sides several times to stretch out the dough surface, and seal at the bottom. 

Wrap your palm around the dough and let it roll within your palm, to shape it.

17. Place the dough into the lined square pan. Spray some water and let the doughs proof for about 30 minutes in a warm oven.

After 1/2 an hour,

18. Preheat the oven to 180 degree Celsius. 
Glide the tip of the pan knife over the surface to draws a slit.

Sprinkle bread flour over.

19. After closing the oven door, reduce the temperature to 160 degree Celsius, and bake at lower rack of the oven for about 10 minutes. Then further reduce the temperature to 150 degree Celsius for 10 to 12 minutes, or till the top turns light brown.

After 10 minutes, reduce the oven temperature to 150 degree Celsius for 10 to 12 minutes.

End of baking.

20. Transfer the hot bread to cool on a wire rack. Enjoy ^^


  1. Replies
    1. Hi Joyce, thank you for leaving me your nice feedback :)

  2. Hi Goh NgaiLeng,I have the purple sweet potatoes powder,can I use it? If yes, how many tbsp u think I must add?tks

  3. Hi Goh NgaiLeng,I have the purple sweet potatoes powder,can I use it? If yes, how many tbsp u think I must add?tks

    1. Hi Hwee Yong, sorry purple sweet potato powder is new to me. But after checking a few recipes which use this powder, i think you roughly can use 27g of purple sweet potato powder and 53g of water to reconstitute 80g of purple sweet potato paste. You may have to do some adjustments on your own :)

  4. Hi ngai leng. Sorry not sure if I posted. Soft pillowy buns. If I were to use orange colored sweet potatoes do I have to make any adjustments. I think the orange ones are wetter. Thanks. Chloe

    1. Hi Chloe, you're right, orange sweet potato is usually has higher water content. You can try to increase the bread flour to about 195g, and keeping the test unchanged. You may need to do some minor adjustment depending on the wetness of the dough:)


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