Purple Yam Tangzhong Buns filled with Purple (?) Chocolate Custard

No there are no artificial colors in these beautiful buns!
Their name;
Purple Yam Tangzhong Buns with Purple(?) Chocolate!
Their colour comes from Purple Yam Powder which is both mesmerising in colour and really nutritious!
Isn't it the most beautiful way to colour your bakes?

What is your opinion about natural vs artificial coloring in baking?
Personally I don't want the artificial ones in my baking.
My background in Biochemistry makes me unable to accept them. They are not a healthy option and their production is not good for the environment either; it consumes a lot of energy and generates waste, contributing to pollution and potential ecological harm.

On the other hand natural dyes are both environmentally friendly and good for our gut and health!
For example Purple Yam Powder is:
High in antioxidants called anthocyanins that give them their distinct purple colour. Anthocyanins possess the ability to reduce oxidative stress and inflammation.

A good source of dietary fiber, which can help regulate digestion and prevent constipation.

Contains vitamin C but unfortunately it denatures at 70C so baking destroys it. Its beta carotene, on the other hand, is more easily available after baking, promoting healthy vision!

Lastly, it lowers blood pressure and helps regulate blood sugar, since Purple Yams have a low glycemix index.

I'd like to hear your point of views on baking dyes!

You can find my recipe in detail in the link in my bio but of course I'll share it in short here too!

For the Tangzhong:
Heat 200gr Water with 40gr Bread Flour and whisk until paste-y.
Bring to room temp.

For the Dough:
Combine the Dry Ingredients:
600gr Bread Flour
8gr Yeast
90gr Sugar
8gr Salt
6gr Milk Powder (optional)

Add the Wet Ingredients to the Dry:
Tangzhong
1 Egg room temp
240ml Warm Milk

Knead for 2 mins and then add:
40gr Softened Butter

Knead for 8 more minutes and meanwhile prepare the Purple Yam Dough Mix by blending:
55γρ Ghee or Softened Butter
70γρ Yam Powder

Divide the dough in two.
Shape one half into a ball and proof in a covered bowl.
Knead the second dough half with the Yam-Butter mix on your mixer until it is evenly purple.
Proof in covered bowl too, for 1 hour or until double.

Prepare the Purple(?) Chocolate Custard:
Heat in a pan until hot:
400gr Milk
150gr White Chocolate
40gr Yam Powder

Mix in a bowl:
100gr milk
3gr Vanilla Paste or Extract
40gr Corn Flour

Add corn flour mix to hot milk and whisk until the custard thickens.
Remove from heat and whisk in 40gr butter.
Let cool in the fridge in a covered bowl.

Back to the dough:
Divide each dough into 8-9 pieces.
Shape into dough balls
Reserve 5 white balls and flatten the rest with a rolling pin.
Put one white ball in a flat purple dough and cover it.
Then cover with a flat white dough.
Do the same with the rest of the dough.

Proof covered for 40 minutes and preheat the oven to 190C
Egg wash (egg yolk+15gr milk) and sprinkle sesame seeds

Bake until golden(20-25mins)
Cool down and then pipe in the Purple Custard.
Rip them open for the custard explosion! 🤤