1. Sweet potato roasted coarse grain wine is brewed by Shandong Sanduo Liquor Co., Ltd., with dry sweet potato as the main raw material and traditional technology. Sweet potato, also known as sweet potato, sweet potato, sweet potato, white taro and so on. Sweet potato belongs to the family Convolvulaceae of the genus Panicum, which is more than 2 meters long and lies on the ground. Its leaves are usually wide oval, 4- 13 cm long and 3- 13 cm wide. Corolla pink, white, lavender or purple, bell-shaped or funnel-shaped, 3-4 cm long, and capsule ovoid or oblate. The main producing areas are Yimeng Mountain in Shandong, Fujian, Henan, Nanchong in Sichuan and other places.

2. Brewing process: selecting high-quality dried sweet potatoes from Yimeng mountain area, soaking, initial steaming, stewing grain, re-steaming, spreading cold koji, fermenting in pond, and distilling the finished product.