Purple sweet potato contains a lot of anthocyanin, which is a water-soluble pigment that can change color with the pH of cell fluid. Cell sap is red when it is acidic and blue when it is alkaline. It is normal for people to turn purple or blue when they meet water. That's because saliva dissolves purple pigment, which is a natural water-soluble pigment and has no harm to human body.

material

250g of high flour, water 150g, fresh yeast 14g, 25g of sugar, 4g of sea salt, 25g of butter and 0/35g of purple potato paste.

working methods

1. Peel the purple sweet potato after steaming, put it in a fresh-keeping bag and crush it with a glass bottle.

2. Use 70g mashed potatoes, add them when the dough is stirred, and then stir until the dough is even pink and purple.

3. Divide into 8 parts after the first fermentation, and divide the remaining mashed potatoes into 8 parts on average.

4. Each small dough is rolled into a cow tongue, and after mashed potatoes are smeared, the dough is rolled up, rounded and discharged into Qifeng mold.

5. The secondary fermentation is expanded to the die mouth and baked at 190℃ for 30 minutes.