A Brief History of Sugar Cane

The following chapter is intended to give a brief description of that which is arguably the main character in this book. It has been included to provide a full picture and understanding of the subject matter under consideration; however it is realized that some or all of this knowledge will be old news to many readers, particularly those in the Bundaberg area. It remains to beg the patience of those readers who may wish to skip a few pages and to carry on into the remainder of the text.

In earlier times, both in England and in Western Europe, the main source of sugar was honey and, to a lesser extent, the seasonal availability of some sweet fruits. Sugar beet was eventually to become the commercial source of sugar to these cold climate lands, but there was a superior source of sugar out there waiting to be discovered and exploited. Natives of the South Pacific islands had, for many generations, been cultivating and harvesting their higher yielding, indigenous sugar cane plant.

Early European explorers in the Pacific Ocean found that the natives of many of these islands were cultivating sugar cane in their gardens, and the people of New Guinea, in particular, had many varieties of cane that were of a very sweet, thick-stemmed nature with a soft rind. At a later date seeds from these canes were used to improve many of the commercially successful, Australian-bred, hybrid varieties.

It is possible that the Melanesians and Polynesians were the first sugar cane breeders. Certainly, in terms of their long exposure to the sugar cane plant and in their desire to obtain a soft rind and pith combined with the maximum sweetness on chewing, they were the first selectors of the best natural varieties. In considering the extent of human migration in prehistoric and historic times, and from island to island in the Pacific Ocean – much of which occurred in relatively recent times – it seems likely that humans themselves may have been a significant agent in the dispersion of such a popular plant. In the Pacific Ocean the effect of cyclones and currents should also not be ignored, given the durability of the cane stalk with its waxy coating and the ability of the plant to strike from stalk fragments.

Sugar cane and the accompanying production of raw sugar migrated, via southern Asia, to India and the south of China well before the beginning of the Christian era. Sugar being then an expensive commodity it was economical to transport it in relatively small quantities from the southern Asian cane farmers to the Near East, by caravan over the land-based trade routes, and by coastal dhow in maritime trading. Inevitably the sugar cane plant was to follow the commodity itself, to be cultivated in the arable lands between the Tigris and Euphrates Rivers.

When the Arabs, under the flag of Islam, conquered northern Africa and large areas of Southern and Western Europe in the seventh century they extended the plant’s habitat from the agricultural areas of the two rivers to the warmer countries of the Mediterranean. The importation of sugar from the Mediterranean area to England occurred considerably later, probably as recently as the 15th century.

At that time, the Venetian merchants were leaders in the transportation and trade of luxury goods to the other ports and cities of the Mediterranean Sea. This luxury trade included the trading in spices and sugar. They became major sugar refiners in their own right and established a pattern of trading and manufacture which survived into the twentieth century. Raw sugar, grown and produced in the cane fields of Egypt, Spain and other warm regions of the Mediterranean, was purchased by the merchants and refined in Venice, for trade with their nearby European markets. For storage and maritime transportation purposes the refined sugar was moulded into conical shapes, much in the way that wine and olive oil storage jars had been configured since ancient times for similar purposes.

At a later date, and on his second voyage, Christopher Columbus introduced sugar cane to the Caribbean. Here it flourished to such an extent that the area was to become regarded as the world’s sugar bowl.

Later again sugar cane from the Cape of Good Hope was taken aboard by the First Fleet, while en route to Botany Bay, and was probably transferred from there to Norfolk Island as, in 1788, Lieutenant Philip Gidley King the then commandant of Norfolk Island reported to Governor Phillip that the sugar cane there was thriving very well. However there appears to be no record of cane having been grown on the Australian mainland until Thomas Alison Scott introduced it from Tahiti in the Society Islands in 1817.

The census of 1836 found that the Colony of New South Wales (there were no separate Victorian or Queensland colonies in those days) had populations of 77,096 people and 3,000,000 sheep. Three years later The Australian Sugar Company was formed in London by a company promoter, Francis Kemble, and the Deputy Lieutenant of the County of Kent, William Knox Child, who had concluded that the colony’s commercial centre Sydney would be an attractive location for a sugar refinery. However, though the necessary equipment was consigned to Sydney, this company was dissolved and a new company, The Australasian Sugar Company, under the management of Edward Knox, emerged to take over and utilize its assets. The manufacture of the refined sugar, from raw sugar obtained from the Philippines, commenced in 1842 when the company was selling lump sugar at 4½d per pound and fine sugar pieces at 2¾d per pound. However supplies of raw sugar for refining purposes did not become available from sources within the colony until the late 1860’s.

To grow sugar cane in the Australian colonies successfully Pacific Island labour had to be imported and The Colonial Sugar Refining Company Limited, which had been formed in 1855 under the guidance of Knox, was to extend its activities outside Australia by establishing a sugar industry in Fiji in about 1880. The cane was being returned to its place of origin; the wheel had turned full circle.

SUGAR THE TRADABLE COMMODITY

The organic chemists’ name for ordinary household sugar is sucrose and it is found in many members of the plant kingdom though in variable quantities. Some examples of other commercial sources of sucrose are sugar beet, the Canadian sugar maple and honey made by the bees from the nectar of flowers. The bees can also have a major effect on the production of other important commercial crops, where their activity can be critical for the crop’s pollination.

The earliest colonial sugar pioneers made raw sugar by methods that had been used in Asia, mainly in India and the south of China, for thousands of years. Here individual stalks of sugar cane were fed into wooden, crushing rollers which were turned either by hand or by a beast of burden such as a draught horse (in Australia) or more likely by water buffalo (in Asia). In all cases the thrust was applied to beams set over circular paths surrounding the crushing rollers. The juice from the rollers was concentrated by boiling over wood fires in open pots. Following concentration the juice was poured into cooling vessels where the sugar crystallized out of the syrup. The crystal and syrup mixture was then transferred into moulds where further cooling occurred and the mix became a solid suitable for consumption or trade.

The more modern milling procedures, that became practical following the development of the steam engine and that became the norm in the Australian colonies, will be described in significantly greater detail in the following pages.

The sugar produced is now transported both by land and sea in very large quantities and a significant amount is refined into the white sugar form.

THE NATURE OF SUGAR CANE

In appearance the sugar cane plant resembles a type of bamboo, with regularly spaced joints or nodes, but it does not have the characteristically hollow bamboo stem. It is a genuine grass, of the Saccharum genus, and traditional varieties could reach a height of three to four metres. However a contemporary crop’s height will be subject to the most recent developments in new cane varieties and is generally more compact with higher sugar content.

The canes of a single plant can form a clump called a stool. Commercial varieties of cane with thick stalks can produce five to eight stalks to a stool, whereas the stools of varieties having thinner stalks may produce up to fourteen or fifteen. The side leaves tend to die and fall off as the plant grows but sufficient are retained in a dry form to provide tinder for the stripping of the cane by fire where this is required to provide the most economical form of harvest. Such a procedure may be required where a natural disaster such as a cyclone disturbs the naturally occurring vertical growth habit of the plant. A green leaf top is always preserved on each stalk and this consists of slender leaves up to one and one third metres in length.

The cane plant flower is typical of that of the grass family, though on a larger scale, and consists of a grey to purplish plume of a feathery nature and up to one and one quarter metres long. A field in full flower is said to be arrowing and can present a very picturesque scene. Under favourable climatic conditions the harvesting of the seed, which forms consequent to this flowering, is essential for the breeding of new cane varieties. However this would not normally be of great interest to the typical cane farmer who plants his new crop by laying 300 mm long cuttings, or setts, of the cane stalk flat in a furrow then covering them with 50 to 75 millimetres of soil. Varietal development has produced more disease resistant cane and more compact stalks having significantly higher commercial sugar content.

The leaf of the plant utilizes a green coloured substance, called chlorophyll, to form the sucrose and it is possible that the sugar cane leaf may be the most efficient sucrose manufacturer of the plant kingdom. The chlorophyll in the leaf absorbs energy from the photons delivered by sunlight and utilizes this energy to combine carbon dioxide from the air with water from the ground to form the sugars glucose and fructose. These building blocks then combine to form the sucrose. This process, where the chemical element carbon is combined with the water’s constituents of hydrogen and oxygen to form a carbohydrate, i.e. a hydrated carbon, is called photosynthesis. Carbohydrates formed in this manner are one of the most important food groups for man and for the herbivore family of animals.

Following manufacture by the sugar cane leaf, the sucrose is transferred to and stored in the cane’s stalk, where it is held until required for the plant’s future sustenance. A new generation of cane stalks will grow from any plant base that has been left in the ground following harvesting.

A ratoon crop is said to have been produced when the plant bases from the previous crop has been preserved in the ground.

The cultivation of a good ratoon crop means that a further harvest can be made without having to incur the expense involved in ploughing out the remnants of the old crop to make way for the new crop’s cultivation and planting. However crop quality will deteriorate without replanting and hence the replanting becomes desirable, possibly after two harvests, to maintain an economic operation.

The sugar cane plant requires abundant, regular moisture, plentiful sunlight and a well-drained soil of reasonable quality. It requires about one thousand litres of water from the soil to produce one kilogram of sugar and, subsequent to its use by the plant, nearly all of this water is transpired. In order for the crop to become rich in sugar it will need a period of relative coolness and a reduction in soil moisture at maturity. This combination has the effect of checking the cane’s growth with the consequent raising of the stalk’s sugar content

The stalk consists of a fibrous, hard rind surrounding more fibres and pith which contains the sugar-bearing cells that are soft and thin-walled. These must be broken down in the mill by the application of friction and pressure to release the sugar-bearing juice. Harvesting commences in the winter months. Under the old manual cutting methods the stalks were cut off at ground level, the residual side and green top leaves removed, either with the knife or by the prior burning-off of the cane plot, and the stalks placed on flat-top rail wagons for transportation to the mill. Cut cane delivery from the field to the cane-train on its permanent rail-lines, was originally via horse drawn, later mechanical traction, vehicles travelling on light, demountable and movable rails. Now however mechanical harvesting, with cut cane placed in bins for delivery to the mill, has become an almost universal practice in Australia, and artificial irrigation has also become widely practised.

When averaged over a season the processed stalks contain about sixteen per cent sucrose by weight. The remaining weight consists of some twelve per cent of fibre, seventy per cent of water and approximately two per cent impurities. A typical Australian mill’s processing of the cane stalks produces approximately one tonne of the raw sugar from seven and one quarter tonnes of the sugar cane.

Evolution of the industry in Australia has resulted in a stable, viable system where a large central mill has feedstock delivered by an efficient short-haul system from many small owner operated farms. In a world of rapidly changing technology and commerce who knows where things will go from here? For example, if the rind, or bagasse, is found to be capable of producing a valuable foodstuff and/ or food additive, a reversion to the older system of small local mills pumping their juice to the central mill, with export of the processed rind to a separate manufacturer, could again become the norm. The dried bagasse can also be used as a fuel source or as a weed inhibitor or soil conditioner.