Sucrose is the chemical name for table sugar. It's a carbohydrate molecule that tastes sweet, making it a popular food additive. Upon consuming sucrose, you can digest and absorb its components into the bloodstream. From there, your cells use the components of sucrose for energy. Plants produce sucrose through the process of photosynthesis, and many plants are natural sources of sucrose.
Sucrose is chemically classified as a disaccharide, which means it's a carbohydrate made up of two smaller sugar units, explain Drs. Mary Campbell and Shawn Farrell in their book "Biochemistry." The smaller sugars that combine chemically to form sucrose are called glucose and fructose. Sucrose tastes sweeter than glucose, which is much more common in nature. It's less sweet, however, than fructose. Your cells can burn the chemical components of sucrose to provide them with energy -- like other carbohydrates, sucrose contains 4 calories per gram.
Sucrose occurs naturally in many plants. It's formed through the process of photosynthesis, which means "building from light." Plants harvest the sun's light energy using chemicals -- including chlorophyll -- in their leaves. They then use that energy to bond molecules of water to molecules of carbon dioxide, explain Drs. Reginald Garrett and Charles Grisham in their book "Biochemistry." This results in formation of sugars like glucose and fructose, which the plant can then combine to make sucrose.
Plants concentrate sucrose and other sugars that they produce through photosynthesis in the fruit of the plant. This is because the fruit contains seeds, which are plant embryos. Sucrose and other stored sugars provide a source of energy for the plant, and in many cases, also encourage animals to eat the fruit. This helps with seed dispersal, as animals spread the seeds over a wide area through defecation. Sweet fruits, and some sweet vegetables, all contain sucrose.
Sources of Sucrose
Some plants concentrate sucrose so strongly that they make good sources of sucrose for production of table sugar. Sugarcane, for instance, contains very concentrated sucrose in certain parts of the plant. Sugar beets are also concentrated sources of sucrose. By growing and harvesting sugarcane and beets, and then pressing the sucrose-rich juice out of the plants, humans can isolate pure sucrose crystals -- this is table sugar.