As a sweet substance, people often consume white sugar, brown sugar and rock sugar. Sugar production method is not complicated, the sugar cane or sugar beet pressure out of the juice, filtered to remove impurities, and then to the filtrate to add the right amount of lime water, neutralize the acid contained therein, and then filtered to remove the precipitation, the carbon dioxide into the filtrate, so that the lime water precipitated calcium carbonate, and then repeat the filtration, the resultant filtrate is an aqueous solution of sucrose. The aqueous solution of sucrose in a vacuum device under reduced pressure evaporation, concentration, cooling, there is a reddish-brown slightly sticky crystals precipitated, which is brown sugar. Want to make white sugar, brown sugar must be dissolved in water, add the appropriate amount of bone carbon or activated carbon, brown sugar water colored material adsorption, and then filtered, heated, concentrated, cooled filtrate, a kind of white crystals - white sugar appeared. White sugar is more pure than brown sugar, but still contains some water, and then the white sugar heated to the appropriate temperature to remove the water, you get colorless and transparent lumpy large crystals - rock sugar. As you can see, rock sugar has the highest purity and is also the sweetest.
Speaking of sweet substances, people naturally think of saccharin, saccharin is not the "essence of sugar", it is not refined from sugar, but to black and smelly coal tar as the basic raw material made. Saccharin has no nutritional value. A small amount of saccharin is harmless to the human body, but excessive consumption of saccharin is harmful to the human body. So saccharin can be consumed, but not more.