Prasanna BD, professor of chemical engineering at NITK, explaining NITK’s patented technology to the Union Education Minister, Dharmendra Pradhan, ‘IInvenTiv 2024’ in Hyderabad last year

The Union Education Minister, Dharmendra Pradhan, tasted a dish made from taro (a root vegetable) at ‘IInvenTiv 2024’ in Hyderabad last February in which premier technology institutions, including IITs and NITs, showcased their research and development (R&D) works at the mega R&D fair.

The dish was prepared from an edible aroid, which usually causes irritation after eating. The dish the minister tasted was prepared using a technology developed by the Mangaluru-based National Institute of Technology Karnataka (NITK). This patented technology helps produce irritation-free, ready-to-cook vegetables from tubers such as elephant foot yam (amorphophallus paeoniifolius), taro (colocasia esculanta var esculanta), tannia (xanthosoma violaceum) and giant taro (alocasia macrorrhiza), collectively called as aroids.

Recently, the Patent Office of the Government of India granted patent to NITK for the invention entitled, ‘A composition for reducing acridity in edible aroid corms and a method of preparing edible aroid corms with reduced acridity’. Prasanna BD, professor of chemical engineering at NITK, and Moni Philip Jacob K, who was an MTech student at the time of research, are the inventors of this technology.

High oxalate content

According to Prasanna, these edible aroids have not realised their full potential as a vegetable and source of starch due to the presence of high oxalate content and acridity. The total oxalate contents can range from 300 mg to 7,500 mg per kg of corms (dry weight basis).

When a person consumes food containing oxalates, it causes caustic effects and irritation to the intestinal tract and affects the bioavailability of minerals such as calcium, magnesium, zinc and copper. The consumption of even moderate amounts of oxalate has been reported to play a key role in calcium oxalate-induced kidney stone disease. Even peeling and cutting with bare hands cause acute skin irritations.

Traditionally, the acridity in these aroids is removed by peeling, cutting and boiling with tamarind, lemon juices or with baking soda. However, none of these methods removes acridity and total oxalate content below the safe limits, he said. As per World Health Organization, the maximum permissible limit of oxalate consumption by humans is 71 mg per day.

Using NITK’s technology, more than 90 per cent of the oxalates that cause biting taste and irritation can be removed without affecting its taste, aroma and texture of the aroids. This technology produces ready-to-cook aroid cubes which can be preserved for a week in the refrigerator and for three months if vacuum packing is adapted, he said. Unpacking the cubes, steeping in water and a thorough wash will make it ready for cooking. Processing causes no change in texture, colour or taste compared to the unprocessed tubers.

On the limited interest among consumers and farmers for these edible aroids, Prasanna said tedious and time-consuming traditional preparatory steps are discouraging urban consumers to use this otherwise cheap and nutritious vegetable. Farmers face up to 60 per cent post-harvest loss during the six-month storage due to high water content in the corms. Due to the limited demand and high post-harvest loss, farmers are getting low prices for these aroids.

On the benefits of this technology to the farming sector, he said the acridity factor is no more a deciding factor for price fixation and demand for these tubers. This technology will lead to increased consumption of the crop and lower post-harvest loss. This assures a stable price and market for these aroids. He suggested that farmer-producer organisations and other retailers can make use of this technology.

Prasanna said NITK is planning to license this technology to entrepreneurs, organisations who are interested in the production of ready-to-cook vegetables for domestic and export markets.

Transfer of technology

In 2021, this technology was transferred to the Bengaluru-based food tech start-up ‘nGV Natural Industry Pvt Ltd’ under non-exclusive, limited licensing agreement. This start-up has successfully produced and marketed the ready-to-cook elephant foot yam in Bengaluru using this technology. The hotel industry is the major consumer of this ready-to-cook vegetable in Bengaluru, he said.

Naveen GV, Founder of nGV Natural Industry, told businessline that NITK’s technology works well, and there is market acceptance for the products prepared using this technology.

He suggested that there is a need to create awareness on the impact of oxalate crystals on health and how this technology helps in tackling those issues. That could help create a good market for these tubers, opening huge opportunities for the growers. NITK’s technology helps provide longer shelf-life for these aroids. He also suggested the need to explore the export market for these tubers by using this technology.

Published on January 20, 2025