Technology of making Liquor from Sweet Potato

Brewing is a process in which starch and sugar are converted into alcohol by fermentation of microorganisms with starch as raw material. In addition to grain brewing raw materials (rice, sorghum), mainly sweet potato as raw materials. Using sweet potato as raw material, the starch utilization rate and liquor yield were higher than those of other grains, while the cost of liquor was lower.

1. Technological process: making wine medicine--raw material treatment--fermentation--distillation--adjustment of wine degree--storage

2, process operation points:

① Wine medicine: Wine medicine can be divided into two kinds: black and white. Baiyao is prepared from polygonum grass and rice bran or rice flour. In addition to the above raw materials, the preparation of black medicine also needs to add tangerine peel, prickly ash, licorice, cinnamon, atractylodes and other drugs. The medicinal materials used to prepare wine and medicine vary from place to place, with more than a dozen or even hundreds of them. These ingredients contain phosphorus, potassium, magnesium, nitrogen and growth stimulants, which are beneficial to the propagation of strains. Wine medicine contains saccharifying bacteria and yeast, starch can be the raw material by saccharification, and then fermentation into alcohol.

Taking Baiyao as an example, the preparation method comprises the following steps of: preparing the raw materials according to 19kg of rice flour, 7kg of water, 500g of aged wine medicine and 150g of polygonum hydropiper. When making, mix rice flour, polygonum powder and water evenly, put them in a wooden cabinet 100 cm long, 60 cm wide and 6~7 cm high, spread flat, compact, and then cover with reed mat for compaction. Cut into small pieces of 2~3 cm square with a knife, roll them on a roller, and roll them upside down. Then move into a shallow wooden dish, add the finely ground old wine medicine and shake it to adhere to the surface of the dough. Then the prepared dough is placed in a curved plate and transferred into a culture room for heat preservation and culture for 1 to 2 days, namely white hyphae and conidia grow. During this time, it was overturned once to facilitate the propagation of strains. At this time, if the temperature is not high, there is no need to open the window for ventilation. After 3~4 days of cultivation, cover the curved plate with cloth, expose it to the sun for about 6 days, and store it in a dry place for ready use.

② Raw material treatment: clean fresh sweet potato and cut it into pieces, mix it with 4%~9% crushed rice bran and heat it to cook, so as to promote starch gelatinization and expansion, so as to facilitate saccharification. When cooking, add 1/3 of the water to the pan first. After boiling, put the material on the bamboo curtain of steaming steamer in several times, steam until the steam rises, and then add the second layer. If the steam is not uniform, add some wet chaff to the weak steam. After all the ingredients are added, cover the pot and cook for 30~40 minutes until cooked and not rotten. Then take it out and spread it on the mat, turn it over and break up the lumps. When spreading and drying, it must be quickly cooled to about 38 ° C, piled into small piles, mixed for the first time, and mixed for the second time when the temperature drops to about 35 ° C (1 kg of wine and medicine can be used for every 100 kg of fresh potatoes). The medicine should be fully mixed evenly. When the temperature drops to 27~28 degrees Celsius, the stack can be closed, and the stack height is about 15 cm. The stack height varies with the temperature (the temperature is slightly thinner, and the temperature is slightly thicker). Sprinkle a little alcohol on the surface. At this time, the stack temperature is about 24 degrees Celsius, and the surrounding of the stack must be insulated. Heat preservation for about 10 hours, when the temperature rises to 30 degrees Celsius, remove part of the insulation material, in case the temperature continues to rise, more than 35 degrees Celsius to stir once. After another 10 hours or so, when the potato material is completely saccharified and has a fresh fragrance, it can be further fermented.

③ Fermentation: Spread the saccharified raw materials and cool them, and add twice the amount of waste tank to mix them evenly. When they are cooled to 24 degrees Celsius, they can be flattened and compacted into the pool. A layer of waste tank or chaff can be sprinkled, and then sealed with yellow mud. If covered with wood or cardboard, it is more convenient for the collection of exhaust gas. A 3 cm square vent hole is left in the center of the pool to collect carbon dioxide for comprehensive utilization. The temperature of entering the pool is about 22 degrees Celsius, and then check 1~2 times a day. After 3~4 days, the temperature rises and the alcohol fermentation is vigorous. When the temperature begins to drop, it can be taken out for distillation. Under normal circumstances, it can be fully fermented in about 1 week. Whether fermentation is complete depends on temperature and exhaust conditions. After the raw materials are put into the pool for fermentation for 8 hours, the temperature rises slowly, when the temperature rises to 35-37 DEG C, the constant temperature is maintained for a period of time, and then the temperature begins to drop, and when the crystal temperature drops to about 25 DEG C, the fermentation is completed. If you check the exhaust condition, put your hand on the exhaust hole 24 hours after the raw material enters the pool, and you can feel the hot air being exhausted from it. After the gradual increase in hot air, fermentation is the most vigorous, 30~60 cm from the vent can feel the hot air exhaust. When the exhaust volume is reduced to no exhaust feeling, it indicates that it has been completely fermented.

④ Distillation: When wine is distilled, it is decided whether to add chaff according to the degree of loosening of wine mash. Sweet potato mash viscosity is generally large, appropriate to add a proper amount of bran, so as to avoid uneven distillation. Distillation on the mash procedures and cooking on the material is basically the same. After capping open cold water, steamed wine due to its different quality, should be stored separately from the head and tail wine, otherwise it will affect the quality. The head and tail wine can be further distilled to make wine. In order to enhance flavor and bouquet, the newly distilled liquor must be aged. In order to remove a small amount of impurities and odors in the wine, sometimes 0.01%-0.02% potassium permanganate and 0.5% activated carbon are added, and it is filtered for 48 hours. However, it must be noted that the amount of potassium permanganate cannot be excessive, otherwise it is harmful to human health.

Adjustment of alcohol content: In order to make the alcohol content in the wine conform to the market standard@#@136 @#@, artificial alcohol content adjustment should be carried out. If the concentration is insufficient, you can add some alcohol in moderation; otherwise, if the concentration is too high, you need to add water to dilute. After adjustment, the wine can be stored in containers.