Introduced from Japan, Purple Potato King Black Sweet Potato is an internationally recognized green health food in the 21st century. It is the ideal high-calcium food for the elderly and children. In 2001, the food quality inspection report of the Ministry of Agriculture resulted in calcium, selenium, copper and zinc. Trace elements exceed ten times that of wheat, corn and similar common sweet potatoes. Now we have developed a variety of black sweet melon products such as natural purple pigment, high calcium noodles, colored dumplings, quick-freezing preservation, refined high-calcium powder, fillings and so on. Black sweet potato "Purple Potato King" is characterized by: potato-shaped long spindle, potato skin smooth, purple black and bright, deep purple potato. After the tubers are disconnected, the purple slurry flows out. After being cooked, it is purple-black, sweet and delicious. Its taste is excellent. It is rich in anti-cancer substances such as selenium and iodine. Its nutrient composition is several times higher than that of other sweet potatoes. It is a feature of urban and rural residents and hotels. And other health foods.