Purple Sweet Potato Black Sesame Swirl Sourdough Milk Bread

Purple Sweet Potato Black Sesame Swirl Sourdough Milk Bread

I wanted to gift a loaf of bread to some friends, and I knew that one of them has seen my last swirl bread and loved it.  So I wanted to bake another version of this but with another variation as I wasn’t sure if they’d like anko or knew what it is.  Since purple sweet potatoes are one of my favorite inclusions after black sesame and go so well with the black sesame’s nutty flavour it was the perfect combination.

Overnight levain build

14 g starter + 86 g cold water + 86 g bread flour left to ferment at 74ºF overnight.

Take butter out when build levain.


For the Black sesame powder


Grind 86 g of toasted black sesame seeds (I used a coffee grinder) then combine with 18 g of sugar.  Cover and set aside until the morning.


Steam and mash a purple sweet potato, you’ll need about 60-80 g or as much as you’d like to make a nice purple dough.


The next morning mix the following except for the butter.

282 g bread flour

1 large egg

30 g sugar

126 g milk

6 g salt


180 g levain 

Mix to full gluten development.


Blend 30 g of room temperature butter with 30 g of bread flour.  This makes it easier to incorporate the butter into the dough.  Add this to the dough until it comes back together. The dough should be shiny, smooth and elastic.

Remove the dough from the mixer, shape into a ball and divide into approximate thirds.  Shape the largest third into a boule and set aside covered with a towel.


Take the smallest third and combine with the black sesame powder and knead by hand until the black sesame powder is well incorporated.  Shape into a boule and set aside under a tea towel.

Finally take the third dough ball and gradually combine with the mashes purple sweet potato smearing it on the surface and folding it in.  Knead until the dough is a uniform colour and smooth.  Shape into a boule and place under a tea towel to rest for 5 mins.


Lightly flour a work surface and the plain dough boule.  Roll out to at least 12” in length and almost as wide as the length of your pan, set aside.  Continue to do the same with the other two balls next rolling the black sesame dough out to at least 12” in length  and placing that on top of the plain rolled out dough.  Finally rolling the purple sweet potato dough out again to 12” and finally placing that on top of the black sesame dough.  


Roll the laminated three doughs out to about 16-18” in length.  Next tightly roll the laminated doughs starting with the short end until you have a swirled log.  Place the log in your prepared Pullman pan with the seam side down (I like to line it with parchment so it is easy to remove from the pan).  Place in the proofing box set to 82-84ºF to proof until the dough comes to approximately 1 cm below the edge of the Pullman pan.  This takes about 8-8.5 hours at 82ºF, the yeast isn’t likely to be osmotolerant so it will take longer than you would normally expect.


At about 30 mins before you think your dough will be at 1 cm below the edge of the pan, preheat your oven to 355ºF with a rack or baking steel/stone on the lowest rack.  At this time prepare an egg wash and gently brush it on the top of the dough.  When the oven is ready 30 mins later, brush the top of the dough again with the egg wash.  Bake for 45 mins turning once halfway through.  Keep an eye on the top crust and be prepared to shield it with either aluminum foil or a cookie tray above if it is getting dark too soon.  After 45 mins remove from the pan to check for doneness.  Place the bread back in the oven for another 5 minutes to ensure that the crust on the sides is fully set and baked.



Remove from oven and place on a rack to cool completely before slicing.


Hopefully my friends will send me some photos of the crumb that I can share.  Fingers crossed that they enjoy this bread and that it was properly proofed and baked.  This is the first time they are having any of my bread that I’ve baked.