Jaggery is manufactured using two different processes. One is a manual process and the other is through automated plants. Most of the jaggery manufacturing happens through the manual process.

Manual Manufacturing: In India and neighbouring countries, jaggery is made predominantly in rural areas by farmers. Although Automated Mills have been invented, but the Manual Jaggery Manufacturing still remains the most widely used and most favoured method of jaggery manufacturing. It is the only method followed all over India. This method seems simple as no machine or electronics is involved in it, but it needs a lot of experience and expertise.

The process of manufacturing jaggery involves crushing sugarcane using a crusher and extracting juice out of it. The sugar cane juice is then poured in a large shallow but thick iron vessels / pan (called Kadhai) and made to boil over earthen ovens. It is continuously stirred using large ladles to avoid sticking at the bottom of the vessel. This boiling and stirring goes on for hours until most of the water from the juice is vapourised and the juice starts to thicken, as the concentration of sugar increases in it. Slowly it becomes super saturated and assumes a golden to golden brown thick paste form. Now, this needs a lot of experience to decide the right moment when the jaggery is done, because any under doing or over doing may ruin the taste.

Some manufacturers also add sodium bi carbonate (Edible Soda) and juice of Lady’s Finger to improve the colour and a local herb (locally known as Veranda in Bengali) to give the jaggery a granular texture respectively. The colour and taste depends upon the degree of boiling. Some people prefer dark jaggery to light ones and vice versa. Now, the thick paste obtained is poured in various molds, pertaining to different quantities. On further condensation, the jaggery solidifies and is taken out of the molds, wrapped in paper and packed in jute or plastic bags. Thereafter, local agents or businessmen collect this jaggery from farmers and sell in local markets. This is why you never see a company tag on any jaggery sold in India. The process for manufacturing Date Palm Jaggery and Palmyra Jaggery remains the same. These two types of jaggery are invariably manufactured manually.

Jaggery making is a popular activity in several parts of India, especially Mahrashtra and Uttar Pradesh; however, the technology used by the manufacturers is quite old. There have been little improvements done in the manufacturing proccess to enhance the productivity of the process. However, some work is now being carried out at Sugarcane and Jaggery Research Center in Kolhapur, TIDE in Bangalore and IIT Bombay.

Manufacturing by Automated Plants: This method of jaggery manufacturing is still in its infancy and is being used in very few countries. There is nothing much to tell about this. Just pour in sugar cane juice from one end, set the plant at required temperature and time, and wait for the jaggery blocks to come out from the other end. The best advantage of using an automated plant over manual method is that you get uniformly processed jaggery, of same colour and taste, in uniformly packed quantities. This method is used only for sugar cane jaggery. So far, there has not been any instance of using this method for Date Palm Jaggery and Palmyra Jaggery.

Now, time for a few words of caution! It is not a good idea to try making jaggery at home. First reason is that getting a thick iron vessel like that will be a problem. Even if you get that, things will be different when you try making at home, to what they do in a large scale. A lot of things, such as even distribution of temperature, proper stirring & final moisture content etc. matter much. Finally, the expertise! Only experts can judge whether the jaggery is done.

A Happy Ending: Did you know that jaggery manufacturing is almost a self dependent process, in terms of energy consumption? The fuel used for boiling the sugar cane juice is predominantly the dried sugar cane remains left after extraction of juice from it. Now, that was funny, wasn’t that?

Sources:
i.    My own experiences with jaggery as I have seen making it since my childhood.
ii.    Wikipedia Pages (For information regarding jaggery made in Myanmar).
iii.    Text book followed in schools.
iv.    Various reports on jaggery published in News Papers, Health Magazines and other media from time to time