Manufacturing Process

Sri Lanka

Manufacturing process:

• Plucking-Only the uppermost foliage on every stem is picked – the famous ‘two leaves and a bud’
• Weight-The total weight recorded for the day’s batch provides a benchmark for quality assessment at the end of the process of manufacture
• Withering- Raw leaf is ‘fluffed’ and spread out to dry on racks or troughs in a well-lit and ventilated space. It will lie here for 18-24 hours, slowly losing moisture and undergoing physical and chemical changes essential to manufacture.
• Rolling- This is a mechanized process in which the leaf cells are ruptured to release enzymes and bring them into contact with air so that aeration can commence
• Aeration- During this critical stage of manufacture, important chemical reactions take place through the action of air on the leaf tissue. Aeration is also sometimes known as ‘fermentation’ or ‘oxidation’.
• Drying- When the right amount of aeration has occurred, the leaf is dried in a dessicator or ‘firing chamber’ at 99-104˚C (210-220˚F) to prevent further chemical changes.

Impact:

Working conditions for pluckers are often poor, with low wages, low job and income security, discrimination along ethnic and gender lines, lack of protective gear and inadequate basic facilities such as housing and sometimes even drinking water and food.

 

China

In total, there are 70,000 tea processing factories in the country. These factories are in direct connection with the tea workers and growers, and they are usually close to the initial tea growers in terms of location. There are three different manufacturing processes that China uses for tea.

• Primary Processing Factory
  • These factories buy fresh tea leaves from local growers.
  • They process around 30 tons a year, and are operational from March-July.
  • They are equipped with withering, rolling, and drying machines.
• Refineries
  • Mass produce tea based on orders of their clients and are year-round operational.
  • Processes around 200 tons ever year with an output value from 100-millions of RMB.
  • They are not capable of large scale production. They need help accumulating capital and usually have loans from businesses.
  • The products are mostly exported to foreign markets.
• Brand Tea Factory
  • They produce high end tea and sell crude tea to refineries.
  • Highly dependent on human labor.
  • processes around 150 tons a year.
  • The only main difference between this and the other productions is that there are brands attached to the products. The quality remains the same.

Environmental Risks

It is during the manufacturing process phase where environmental risks effect the way tea is produced. In China, air and water pollution are very big environmental risks that often effect the manufacturing process. Also, damaged vegetation and the pollution of soil from pesticides are also main environmental risks.

India

Manufacturing Process:

 The harvested green tea leaves are brought by truck to dry in troughs.

 Fans blow hot and cold air through green leaves to reduce moisture content which is called chemical withering and the resulting limp and dry leaf is called physical withering.

Withered leaf is either rolled or rotorvaned before it goes through to CTC (crush, tear and curl) or Orthodox processing method.

 Fermentation – oxidation happens during this process for both CTC and Orthodox “maal”. There are different fermentation processes including “Gumlah”, “floor fermentation” and “Continuous Floor Fermentation.”

 Dryers – “maal” is fed into dryer to stop fermentation process. All fermented CTC tea is dried in VFBD (VibroFluidised Bed Dryers.) Dried green Orthodox tea is dried using conventional dryers.

Tea is then sorted and graded either primary or secondary grades and passed through different size meshes. Primary grade make up 90-94% of the product line. The bulk tea is then measured and sorted into Kraft paper sacks, sealed and vacuum packed to  keep the tea as fresh as possible.

Packing – an invoice (lot) of tea is created. Invoices can vary from 10-100 paper sacks and each invoice is given a unique identity number which allows that lot of tea to be traced throughout the entire process moving forward. The packed tea is sent to centers and ports in containerised trucks.

Impact

The process of drying tea requires a lot of energy – the UNEP calculates that it takes 8 kWh (kilowatts per hour) or energy to process one kilogram of finished tea compared to 6.3 kWH required to process steel. Older factories use firewood in the drying process which causes deforestation and emissions from burning of the firewood and heat generated by dryers all have a negative environmental impact. (Friends of the Earth, September 2013)

Some recycling initiatives are taking place to reduce impact of tea manufacturing in India.

Tata returns packing material scrap to vendors, plastics are recycled, tea waste are sent to instant tea operations for extraction of solids which are used and converted either into vermicompost on the estates or made into briquettes to be used as fuel for boilers

Vermicomposting –Tata uses a plant-to-soil cycle to build essential soil fauna and flora as well as add in organic matter content into soil for improved nutritional efficiency

Tata trains and employs disabled children to extract green dye from tea wastes which is recycled and reused for dying other items. The issue of training and employing disabled children can be seen as a positive thing or a negative thing – positive that they are taking the initiative to train and give them the opportunity to be productive citizens, negative because they are using children for labor and possibility manipulating these children for their own initiatives. (Tata)

Carbon footprint –for tea – 21g C02 equivalent – add cow’s milk and the footprint is 53g of C02e (milk high carbon product due to methane emissions of cows, adding boiling water adds again … something to think about when making your next cup of tea