Making refined sugar

Sugar Australia is the nation's leading producer of refined sugar products. Our Racecourse Refinery in Mackay is Australia's largest and most advanced sugar refinery, producing a range of refined and specialty sugars under the iconic CSR sugar brand. Our other refineries are located at Yarraville in Victoria and Auckland in New Zealand. The Racecourse Refinery is located beside Mackay Sugars Racecourse Mill, which supplies most of the raw sugar processed there. Each year the factory refines more than 300,000 tonnes of white sugar, 20,000 tonnes of specialty sugars and produces around 12,000 tonnes of molasses. The refinery employs 45 Queenslanders and we're proud to be part of the sugar supply chain, which begins in the cane fields of Mackay and ends in homes throughout Australia and Asia. Refined sugar starts as non-food grade raw sugar. The first step in the refining process is receiving raw sugar from one of the Mackay mills. The load arrives by truck and is tipped into an automated unloading hopper that's connected by conveyor belt to the refinery's 1,000 tonne holding bin. The raw sugar is delivered to the refinery at a rate of 55 to 60 tonnes per hour. The refining process begins when raw sugar is mixed with hot, concentrated syrup known as raw wash. This mixture is known as magma and its density is closely controlled before it's put through the centrifuge, where it's spun at rates exceeding 1,000 revs per minute. When the crystals are spun at high speeds, the sugar and syrup separate. To help this process, hot water is sprayed onto the magma, forcing the syrup and impurities through the tiny holes in the screen. What remains is affined raw sugar crystals. An added benefit of this process is the removal of around 30 per cent of the colour from the original raw sugar crystal. The affined raw sugar is dissolved in hot water at 80 degrees to form melter liquor. The sugar content of this liquor is about 65 per cent. The liquor is then passed through a coarse screen to remove large particulate matter. The next step is the clarification process known as phosphatation. This is where lime and food grade phosphoric acid are added to the melter liquor. Fine bubbles of air are introduced along with a flocculant. This helps bind the impurities together and float them to the surface of the clarifier vessel. This floating layer is known as scum. Once it's removed, we are left with clarified liquor. The clarifying stage is critical in the refining process as it's where most of the impurities are removed from the liquor stream. The next stage involves the clarified liquor being heated further, then put through sand and gravel filters before being sent to the activated carbon columns. The activated carbon columns are where the majority of colour is removed from the liquor. The carbon works much like a fish tank filter. It removes organic and other residual material resulting in a further 85 per cent colour removal. Liquor colour is one of many parameters closely monitored by the refinery lab staff. Based on lab results, small adjustments are made to factory parameters to ensure the refinery produces a consistent quality product that is always in spec. Sugar Australia's Mackay and Yarraville refineries produce some of the best quality food grade sugar in the world. Once the liquor is passed through the carbon columns, it is known as fine liquor. Excess water is then removed from the liquor by passing it through a triple effect evaporator. This concentrates the liquor from 65 per cent sugar content to 78 per cent sugar content in an energy efficient way. From here, the liquor is moved to vacuum pans where it is seeded with CSR caster sugar to grow the sugar crystals. This automated process produces batches of sugar crystals that are consistently the desired size. The thick sugar syrup mix known as Massiquite now moves to the final centrifuge where it is spun at speeds in excess of 1,000 revs per minute. The refined fugules remove the syrup from the mix. The amount of wash water added to the mix during the spin cycle will dictate the final colour of the sugar crystals. The syrup is either returned to the pans to grow more sugar or is used to make CSR branded raw sugar, caster raw sugar, coffee sugar or demerara sugar. The food grade sugar manufacturing process is almost complete. The sugar crystals are now sent to a large rotary dryer where warm dry air is used to remove excess moisture. The dried sugar is then air conditioned and dehumidified in a 3,000 tonne conditioning silo. The final product remains in the silo for 24 to 36 hours before being transported 13 kilometres away to our Mackay Port Terminal to be packaged and distributed. The Mackay Port Terminal employs more than 20 people and serves as a warehouse, packaging facility, distribution centre, bulk sugar storage facility and ship loading facility. Each year the terminal handles just under 300,000 tonnes of locally made sugar and packs more than 43,000 tonnes of sugar for retail, food service and industrial customers. This includes packing raw sugar, raw caster sugar, white sugar, demerara, extra coarse white and coffee sugars under the CSR sugar label. The port also ships around 250,000 tonnes of bulk and packaged white sugar to our Sydney silo located at Glebe and to an international customer in Singapore. Once the sugar leaves the port, it is destined for warehouses from where it is either shipped to overseas markets or delivered to Australian supermarkets, food service customers or industrial customers. Many of the products made at the Racecourse Refinery in Mackay find their way into much-loved home recipes, cafe and restaurant dishes, popular foods and beverages and a wide range of confectionery items. Sugar Australia is proud to be part of the refined sugar story.