yam powder belongs to the 312 group in the 3th category of trademark classification. According to the statistics of signpost. com, there are 47 registered trademarks of yam powder. Yam powder is a well-known nourishing product. It contains protein, sugar, vitamins, fat, choline, amylase and other ingredients, and also contains iodine, calcium, iron, phosphorus and other indispensable inorganic salts and trace elements. It contains enough fiber, which will cause satiety after eating, thus controlling the desire to eat.