Sugar cane
Family Gramineae (or Poaceae)
Saccharum officinarum, sugar cane (S. officinarum 1), is a perennial grass with a solid stem; 2-6 m in height, composed of a series of joints each consisting of a node and an internode. The cane stems, which are of different length, diameter, shape and colour (S. officinarum 2) contain sugar. Most varieties seldom produce inflorescences.
Propagation is by means of cuttings which produce roots on the nodes (S. officinarum 3). After about a year the first harvest of stems is ready to be taken (S. officinarum 4). After the cutting, the plant produces successive crops of stems, but the yield declines slowly and after two or three crops have been harvested, replanting is undertaken.
Use
After cutting, still mostly done by hand, the stems are defoliated (S. officinarum 5) and transported to the factory (S. officinarum 6). Here the stems are crushed and the content mixed with water to obtain as much juice as possible. Next, the juice is concentrated to thick syrup, which is allowed to stand to crystallize the sugar. This raw sugar is usually refined in the importing countries by washing and recrystallization. It may be used as granulated sugar, lump sugar or ground as icing sugar. Molasses is one of the most important by-products from the manufacture of cane sugar. It is the stark brown liquid discharged by the centrifugals after no more sugar can be separated from the pulp. By fermentation, followed by distillation, rum is produced. Industrial alcohol, acetone and other products are manufactured from molasses as well. Bagasse, the fibrous residue left after the extraction of the juice from the cane, is used for the manufacture of paper, cardboard and fibre board. It is also used as fuel in the factory.
Distribution
Sugar cane originated in the South Pacific. It was taken, along with the coconut, from there to Hawaii about 800 AD. Most probably sugar cane was first used for making sugar in India. Both cane and sugar are reported by Alexander the Great during his campaign in India in 326 BC. It took another 500 years until the plant reached Egypt. Eventually it reached Persia in the 6th century and from there the Arabs took it to the south of the Mediterranean. It reached Spain in 714. The Portuguese introduced it into Madeira about 1420 and consequently it reached the Canary Islands, the Azores and West Africa. Columbus took it to the Dominican Republic during his voyage in 1493. From there it was taken to Mexico in 1520, Brazil in 1532 and eventually it reached the West Indies.
Sugar cane was the first crop to be cultivated on large scale in the tropics. After the abolishment of slavery in 1873, there was an acute labour shortage, resulting in the establishment of Indians in many sugar-producing countries, a situation that still can be faced today.
The biggest sugar producing countries are India, Brazil and China; chief exporters are Cuba and Hawaii. Biggest importers are the US and England. The highest yields are obtained on Hawaii with an average of 22 tons of sugar per hectare. The largest consumption per head is in Ireland with about 60 kg per annum, followed by the Netherlands with 54 kg, Australia with 52 kg and the UK with 48.5 kg. There are approximately 7 million hectares of sugar cane in the world producing more sugar than the sugar beet industry.