Turmeric

Overview

Scientific Name: Curcuma Longa

Plant Part: Root or Rhizome

Other Names: Haldi, Kurkum, Curcuma, Besar, Nghệ, Zerdeçal

Turmeric is the rhizome or root system of a flowering plant called Curcuma Longa which belongs to the ginger family known as Zingiberaceae. 

Native to India and Indonesia, turmeric has been used for thousands of years as a natural dye, in food as a spice, and also in medicine and cosmetics.

The main active ingredient in turmeric is Curcumin, an anti-inflammatory agent that may be used to treat a range of medical conditions. 

Often referred to as the Golden Spice because of its colour, turmeric has a warm, bitter, and earthy aroma somewhat similar to Black Pepper.

The Curcuma Longa plant grows to a height of 1 meter and has long oblong leaves that have a burgundy-colored vein running in the middle, with flowers that are funnel or canonical-shaped and can be white, yellow, or pinkish purple colour depending on the variety of turmeric.

The flowers emerge in the middle of fleshy, layered bracts at the center of the plant, often hidden between the long leaves.

The plant thrives in tropical conditions in areas up to 1500 meters above sea level, at temperatures ranging between 20 to 35 degrees celsius.

Turmeric powder is obtained from the rhizomes after they are removed from the ground and then dried before being pulverized, also, the same rhizomes are preserved and used for future sowing purposes.  

History of Turmeric

The use of turmeric dates back more than 4000 years ago in India where it was used for culinary purposes and also held a religious significance. It also appears in Ayurveda texts from roughly 250 BC where it is recommended for relieving the effects of food poisoning. 

The use of turmeric in medicine can be attributed to bioactive compounds called curcuminoids that are known to have anti-inflammatory, anticarcinogenic, and antitumor properties.

Excavations from the Indus Valley Civilization dating back to approximately 2500 BCE have found traces of eggplant, turmeric, ginger, and garlic in pots that were used for cooking. 

Throughout history, merchants were responsible for taking the spice to other parts of the world including China by 700 AD, East Africa by 800 AD, West Africa by 1200 AD, and Jamaica in the eighteenth century.

Notes belonging to the great Venetian explorer and merchant called Marco Emilio Polo mention the use of a vegetable that exhibited properties of saffron in terms of colour but wasn’t really saffron. Thus, in medieval Europe, the term Indian Saffron was given to what we know as turmeric today.

Harvesting and Post Harvesting Practices

Each turmeric variety has its own sowing and harvesting season, the crop is generally ready for harvest in 7-9 months. December to March is considered the harvesting time across various regions of India.

The plants are ready for harvesting when the leaves and stems start to dry out and turn brown.

Harvesting involves removing the whole plant from the ground and put through a number of different processes before the final product is ready for human consumption.

Sweating

During this process, the leaves and the stems of the turmeric plant are removed and the roots are washed to remove any excess soil.

The fingers and the main bulbs are separated from the root system of the plant also known as rhizomes. Bulbs are also known as the mother and are kept for future sowing.

Both the bulbs and fingers are collected separately, then covered with leaves and left to sweat for one day.

Curing

The next step in the post-harvest processing of turmeric involves boiling the fingers and the bulbs in water for up to 1 hour. This is generally done in smaller batches of 50 to 75 kgs using a  perforated container as this allows for better results in terms of uniform curing.

Curing has several advantages including a uniform final product in terms of colour and moisture level, a reduction in the bacterial load, and also a reduction in the drying time of the rhizomes.

Drying

Once the curing is completed, the next process involves cutting the fingers into smaller pieces or slices in order to achieve lower moisture content in the final product to avoid any fungal or bacterial growth during storage and transportation.

The fingers can either be cut by hand or by using machinery. 

Once sliced, the turmeric fingers are then spread out on a mat and exposed to the sun. 

The drying process can take anywhere from 10 to 15 days depending on the intensity of the sun that it is exposed to. The target moisture content of dried turmeric should be 8 to 10%.

It is recommended that the turmeric is heaped and covered in order to protect the produce from dew. 

Drying can also be done using mechanical driers whereby the turmeric slices are evenly distributed on large trays and then hot air at about 65 degrees celsius is passed through a chamber containing the tray.

Polishing

Polishing is the second last step in the post-harvest processing of turmeric and involves polishing turmeric by hand whereby the turmeric fingers are rubbed against a rough surface in order to remove the outer skin and any remaining roots and other particles.

This process helps the turmeric finger or bulbs to obtain its bright yellow colour as you would see in a grocery store.

Another method of polishing turmeric fingers is to use machinery that comprises a drum that is either rotated using an electrical motor or can also be rotated by hand.

The turmeric fingers are placed inside the drum which contains perforated screens with an abrasive surface on the inner side, this causes friction as the drum rotates resulting in the fingers getting cleaned and polished.

The latter method is preferred due to the quality of the product that is obtained i.e. a smoother, evenly polished end-product. 

Grinding

Turmeric cannot be consumed as dried fingers and bulbs therefore it needs to be ground into a fine powder. This can be done utilising Industrial grade pulverizers or grinders. Once ground the powder is passed through a series of fine sieves to eliminate any larger pieces. This results in a fine powder, as we know turmeric sold in supermarkets around the world.

Grinding can take place using different types of mechanical principles, some producing more heat than others. This leads to the loss of essential oils, oleoresins, and curcumin content.

Our Supply Chain

The Sabor Co. has developed strong relationships with farmer-partners in the following countries.

We are currently working with farmers across India including Kerala, Tamil Nadu, and the northeastern state of  Meghalaya to bring you 3 different varieties of turmeric with different levels of Curcumin. Read more

Wholesale and stockist enquiries including product information, specifications, stock availability and pricing.