China is one of the earliest countries in the world to make sugar from sugarcane, with a history of more than 2,000 years. Almost all sugar is composed of sucrose, and the sucrose content of sugar is generally above 95%. All plants with high sucrose content can be used as raw materials for sugar production.

At present, the main raw materials of sugar in the world are sugarcane and beet. Although the raw materials for sugar production are different, there is no difference in quality between sucrose and beet sugar, and the national standard for white sugar is also applicable to them.

Sugar juice is extracted from sugarcane and beet in the factory, and after boiling and concentration, sugar crystals are separated from the center, called crude sugar (or raw sugar), which is light brown. After refining, crude sugar has become white sugar for daily consumption. Besides sugarcane and beet, white sugar can also be processed from sugar with high sucrose content such as raw sugar and coarse sugar.

Most developed countries in the world adopt the two-step method of raw sugar and refined sugar, that is, the production mode of "field sugar factory (producing semi-finished raw sugar)+refined sugar factory (producing refined sugar)", which produces raw sugar first and then refined sugar. Most sugar factories produce raw sugar, and then supply it to refining sugar factories for refining to produce refined sugar, which is used as edible sugar supply market. "Two-step method" is conducive to improving industrial concentration, rationalizing product division of labor and improving professional level. The biggest advantage is that it can achieve balanced production of sugar and balanced market convergence, and solve the contradiction of excessive competition brought about by centralized listing in the cropping season. However, sugar factories in China all adopt one-step production, and most of the white sugar produced has high sulfur dioxide content, color difference and low quality. At present, the sugar produced in China can't enter the futures markets in London and new york due to the low overall grade of the products. Only a few sugar factories can meet the sugar standards of internationally renowned beverages such as Coca-Cola and Pepsi. Guangxi Guitang took the lead in adopting the "two-step" production method and achieved success. The consumption of sugar cane per ton is 0.55 tons less, and the consumption of water, electricity and steam is saved by more than 10%. The direct tax profit of foreign sugar factories increased, and farmers' income increased. At present, the "two-step" production organization form is only adopted in Guangxi, and it is still in its infancy, and it will take time to do a lot of work for large-scale promotion.

At present, there are three kinds of sugar making methods or clarification methods adopted by countries all over the world, namely lime method, sulfurous acid method and carbonic acid method. Lime method can only produce coarse sugar with dark color, while sulfite method can produce white sugar for direct consumption (the produced white sugar is called sulfide sugar). Although the whiteness and sugar yield of white sugar produced by sulfurous acid method are worse than that by carbonic acid method, sulfurous acid method is still widely used in large, medium and small sugarcane sugar factories in China because of its advantages such as short technological process, less equipment and less clarifier. In foreign countries, in recent ten years, with the increase of refined sugar consumption, many sugar factories using sulfurous acid method have successively changed to lime method to re-dissolve and refine the produced crude sugar. However, in developing countries, sulfurous acid method still occupies an important position. The method of clarifying sugarcane juice with lime and carbon dioxide is called carbonation (the sugar produced is called carbonated sugar). Carbonated fabia sulfuric acid method can remove more non-sugar substances, and the total recovery rate is higher. The finished sugar has high purity and low color value, and can be stored for a long time without discoloration. However, the carbonation method also has some disadvantages, such as complex technological process and more mechanical equipment; It also consumes a lot of lime and carbon dioxide, so the production cost is higher. Especially in the areas where sugar factories are far away from limestone producing areas, the popularization of carbonation method is limited to some extent.

In China, the sugar production period is from June 10 to September of the following year, the sugarcane planting season is from June1/kloc-0 to April of the following year, and the sugar beet planting season is from June 10 to February of the following year. Sugarcane sugar factories begin to press in succession from 165438+ 10/0 every year, among which Hainan and Zhanjiang in Guangdong started to press earlier, Guangxi sugar factories started to press in succession from 65438+February, and Yunnan Province started to press at the latest. Most sugar factories in Yunnan started to press in the following year from 65438+ 10/0, and the latest end of the sugarcane pressing season was June. According to relevant statistics, the 2002/2003 crop season lasted for 256 days, and the 2003/2004 crop season lasted for 267 days.