Processing Methods and Technical Key Points for Sweet Potato Crispy Cakes

1. Pulping: Peel and wash fresh sweet potatoes, then pulp them with a pulping machine or chop them and grind them into a fine slurry with a stone mill.

2. Filtering: At a ratio of 1 kg sweet potato slurry to 1 kg clean water, place the sweet potato slurry water in a large vat, add clarified limewater, and mix well. The amount of lime used is 0.5%-1% of the weight of the fresh sweet potatoes. Filter the sweet potato slurry water through filter cloth to remove residue.

3. Settling: Let the filtered sweet potato slurry water stand for 12-24 hours. Remove the yellow water and slurry water to obtain crude sweet potato starch.

4. Drying: Take out the sweet potato starch blocks and dry them in a dryer at 60°C-80°C or sun-dry them for later use.

5. Steaming: Add an appropriate amount of clean water to the dried sweet potato starch and knead it into long tube-shaped dough pieces 4-5 cm in diameter, then place them in a steamer and steam for 40-60 minutes.

6. Slicing: After evenly coloring the surface of the steamed dough pieces with an appropriate amount of food coloring such as carmine or amaranth red, spread them in a winnowing basket and air-dry until they no longer stick to the knife, then cut them into very thin slices and sun-dry for later use.

7. Deep-frying: Put the sun-dried sweet potato dough slices into a boiling oil pot and fry until they expand and become crisp, then remove.

8. Sugar coating: At a ratio of 0.7-0.8 kg white sugar per 1 kg fried sweet potato slices, dissolve the white sugar with a small amount of clean water and boil until a drop of the sugar liquid placed into cold water forms a “bead”; then stop heating. While hot, evenly drizzle the sugar liquid over the sweet potato slices. Then place the sweet potato slices in a 60°C oven to dry or sun-dry them; this is the finished product.