BYPRODUCTS OF SUGARCANE

At the beginning of this century world sugar production, from all different sources, amounted to 12 million tons and per capita consumption was 8 kg. Production will have grown tenfold and per capita consumption by three times, by the end of this century. Even with the appearance of new sweeteners on the market, sugar is still the most widely used caloric food in all countries, especially among those of lower income. Its outstanding value for health improvement becomes more evident every day, mainly when it is used in the less refined form.

The international sugar market will show different characteristics in the next century: It will be a deregulated and highly competitive market; exports will be concentrated, with more than 70 percent accounted for by the five leading exporters, the European Union taking the first place. Eighty percent of imports will be made by the less developed countries compared to only 30 percent in 1970. Alternative sweeteners will slowly continue to increase their presence with an expected 16 percent of the market in year 2000 compared to 13.5 percent in 1994 – 95. Prices are forecasted to be at a level of 22 – 27 US cents per kg (10 – 12 US cents per pound) with a total trade volume of 28 – 30 million tons in the year 2000. World food demand at the beginning of next century will be twice as much as three decades ago; less developed countries will need to increase their production by one and a half times to simply meet the requirements of their increasing population.

The energy problem is another issue that will have to be faced and will require more emphasis in planning for next century. World energy consumption has grown to such an extent that what is spent on oil during this decade will be as much as all the expenditures on oil over the last 100 years. It is in this context that the rationality of the sugar industry diversification must be defined. New trends in biotechnology, the search for new materials, the preference for renewable products of natural origin and other development opportunities are emerging that could raise the  added value of raw materials from 5 to 20 times, depending on process complexity and efficiency.

1.     Bagasse

The bagasse (or the crushed cane fibers), which results from the milling, is used in the boilers for steam production which is used to power the process. The surplus bagasse is used in industry, to produce power, make paper, building materials, as a fuel and even as stock feeds.

2.     Confectionary

Sugar cane was a very important part of the primitive diet. Chewing the peeled, raw cane was one way that primitive peoples obtained the goodness from Sugar Cane.

Today, sugar confectionery includes a large range of food items, commonly known as sweets. Some examples are; Boiled sweets, Toffees, and Marshmallows.

3.     Rum

Some distilleries use the fresh juice of sugar cane as the raw material for the Rum spirit, and other distilleries use a byproduct of the sugar refining process known as molasses as the raw material for the fermentation process. The fermentation process requires the addition of yeast to the raw material which converts the available sucrose to alcohol. Some prefer fresh rum, but most consumers prefer the more elegant taste of an aged spirit. Almost all rum is aged in used oak barrels that once held whiskey or bourbon. Aging can last from one to thirty years or more, making rum one of the most varied of the distilled spirits. During the aging process the rum acquires a golden color that changes to a dark brown with time.

4.     Paper

Bagasse is among the world’s most widely used and available non wood fibers. Bagasse is the most eco-friendly renewable resource for paper making. Tamil Nadu Newsprint and Papers Limited use about 800,000 tons of Bagasse a year replacing wood in the manufacture of paper. Paper mills located close to sugar cane farming regions can take advantage of a year-round supply of fiber, as bagasse can be stored in warehouses and used on demand. Kimberly Clark is a major producer of bagasse paper, primarily for paper towels and tissues. Their Orizaba, Mexico mill produces some 300,000 tons of paper products per year.

5.     Ethanol

Sugarcane can also be used to make ethanol, a liquid that can be used as an automotive fuel or a gasoline additive. Gasohol, a mixture of 10 to 25 percent ethanol with gasoline, is commonly sold in place of gasoline in many nations. Gasohol, which can be used in any gasoline burning engine, has many environmental advantages. Ethanol can also be used directly as an automotive fuel in specially designed engines. In Brazil, about 40% of the automobiles are designed to burn pure ethanol and the rest use gasohol, as a result of the Brazilian Fuel Alcohol Program, one of the largest commercial biomass energy projects in the world.

6.     Stock Feeds

Cellulose is the world’s most widely available renewable resource, amounting to about fifty per cent of the cell-wall material of woody and herbaceous plants. Due to this abundance and renew ability, there has been a great deal of interest in utilizing cellulose as a feedstock. One potential use of bagasse is as a feedstuff for cattle, because the components of bagasse are in their natural, resistant conformation, susceptibility to enzymic hydrolysis is extremely limited. Sugar-cane bagasse contains more than 60% of its dry matter in the form of cellulose and hemicellulose but its degradability is very poor. To be suitable as stock feed, bagasse is treated with high pressure steam.

7.     Building Materials

Bagasse is commonly used for various building boards whose acoustical properties make them very desirable for homes, offices, and other buildings. Bagasse & wood fiber are made as one of the most important particleboards in the building industry by a process similar to paper making. A wide variety of bagasse & wood fiber particleboards have been used successfully for low-cost housing, residential buildings, schools, offices and administration-buildings, etc.

8.     Fuel and Power

Bagasse is used as fuel to run the mills and often to make electricity. Another general use made of sugarcane throughout the world is as a source of heat. In some areas, the cost of bagasse fiber fluctuates with the price of oil. When oil is expensive, there is a greater demand to use bagasse as a cheap fuel to burn. There has been impressive progress in biomass based power generation, both in sugar mills and for Independent Power Producers. Considerable change has occurred in respect of the utilization of bagasse in sugar mills for efficient steam and power generation. The furnaces, primarily designed in the early days for incinerating bagasse, have been replaced by highly energy efficient combustion systems for co-generation including surplus generation to utility grids.

Biomass, at one time, considered to be the fuel of the poor in the developing countries, has now become an important source of energy for developed countries as well. Biomass’ role in building the economy while preserving the environment has attracted large allocations for technology adaptation and development leading to more efficient methods of biomass conversion into useful energy.

By

SAJJAD AKHTAR** (M.Sc. Hons.), Dr. MUHAMMAD AHSAN*, Dr. FAROOQ AHMAD KHAN*, ZAHOOR AHMAD ^a(PhD Scholar) AND MUHAMMAD REHAN ASLAM ^b (M.Sc. Hons.)

           **, * Department of Plant Breeding and Genetics (PBG), ^a Department of Crop         Physiology, ^b Department of Agronomy

University of Agriculture Faisalabad Pakistan