The following points highlight the six main steps involved in manufacturing cane-sugar. The steps are: 1. Extraction of the Juice 2. Clarification of Juice 3. Concentration and Crystallization 4. Separation of Crystals 5. Refining of Sugar 6. Recovery of Sugar Molasses.

1. Extraction of the Juice:

The canes are thoroughly cleaned and cut into small pieces. These cane pieces are dropped over a continuous belt of steel plates called the cane-carrier, moving over roller chains. From the cane-carrier, these are conveyed to a crusher fitted with a set of revolving knives, and cut into very small pieces.

These small pieces in the form of a compact blanket are made to pass through two roller crushers and four sets of mills. After major quantity of the juice has been extracted by the crushers and the first two mills, cold or hot water is sprinkled over the bagasse whereby residual juice gets diluted and can be easily extracted by further milling.

About 90-95% of the juice is usually extracted. The juice extracted is weighed or measured as desired and sent for clarification.

In case sugar is to be extracted from sugar-beet, it is sliced and put in hot water when the sugar present in the beet diffuses out. A number of tanks are used and worked on the principle of counter currents—concentrated solution comes in contact with fresh slices and the exhausted slices come in contact with fresh water and lose last traces of sugar in them. The solution obtained is treated like cane-juice.

2. Clarification of Juice:

The raw juice is dark opaque liquid containing about 15% sucrose and small quantities of glucose, fructose, vegetable proteins, mineral salts, organic acids, colouring matter, gums and fine particles of bagasse suspended in it.

Allowed to remain untreated tor some time, it begins to ferment and the sucrose present changes to mixture of glucose and fructose. In order to avoid this, the juice is not allowed to stand untreated for a long time.

There are two main processes for clarification of juice:

(i) Sulphitation:

Adding milk of lime and treating with sulphur dioxide.

(ii) Carbonation:

Adding milk of lime and treating with carbon dioxide.

Both processes have advantages of their own. In fact combination of both is made use of to get better results.

(a) Defecation:

The juice is strained to remove suspended matter and treated with 2-3% lime till pH value reaches 7.2 in tanks heated with steam coils.

Heating of the juice helps the coagulation of albuminoids by lime. The