Brownsugarexporter.com
- Queensland's 23 sugar mills are in close proximity to the farms which supply
them with cane. The mills operate during the harvesting and crushing season
which extends from June to December. Raw sugar produced by these mills is
stored at bulk sugar terminals before being sold to Australian and overseas
refineries. The exception is the new Tableland mill whose syrup is transported
to the company's coastal mills, Babinda, Mourilyan and South Johnstone, where
raw sugar is then made.
To avoid deterioration in the sugar content levels, sugar
cane is delivered to the mill with minimal delay after harvesting. This has led
to the development of an extensive transport system which allows harvested cane
to be moved quickly and efficiently to sugar mills by either road or rail.
Queensland mills own and operate approximately 4,000 kilometres of narrow gauge
railway.
At the mill, the sugar cane is crushed by large rollers. The
extracted juice is then clarified to remove soil and impurities. This juice is
concentrated into a syrup by boiling off excess water, seeded with raw sugar
crystals in a vacuum pan and boiled until sugar crystals have formed and grown.
The boiled mixture is centrifuged to separate the molasses from the crystals,
which are tumble dried and placed in large storage bins for transport to bulk
sugar terminals or refineries.
Recent technological advances in milling procedures and mill
equipment have contributed to the efficiency and high quality of Queensland's
raw sugar industry.
Most raw sugar requires further processing at refineries in
order to meet food manufacturers and consumers needs.
The main products from Australia's refineries are white
crystal sugars, brown sugars, liquid sugar, golden syrup and treacle.
At the refinery, the raw sugar crystals are washed and
dissolved in hot water to form a syrup. Phosphoric acid and lime are added to
the melted sugar to remove any impurities in the clarification process. The
syrup is pressure filtered through cloth, passed through decolourising columns
containing activated carbon, boiled in a vacuum pan and seeded with fine sugar
crystals. When the crystals are large enough, they are discharged from the pan,
centrifuged to remove excess liquid and then tumble dried. The dried sugar is
then graded into required sizes prior to packaging and supply to customers. (BD)