Incredible onions: Gamma rays to keep stocks strong and healthy in storage

Maharashtra cultivates 43% of India's onion, followed by Madhya Pradesh (15%), Karnataka (9%) and Gujarat (9%). (Photo: Bloomberg)
Maharashtra cultivates 43% of India's onion, followed by Madhya Pradesh (15%), Karnataka (9%) and Gujarat (9%). (Photo: Bloomberg)


  • Irradiation centres will be set up in Maharashtra, the country's largest producer of the daily staple, to reduce post-harvest losses of onion stocks

For an onion bulb born in India, life is often short and brutal. Nearly a fourth of the harvest rots and sprouts on its journey from the farm to the fork. Now, technology is set to give it an extended lease of life, beginning with the country's largest producing state: Maharashtra.

Irradiation units will come up at two to three locations in the state where 25,000 tonnes of onion will be treated, a government official said on condition of anonymity. The units, which will be in addition to the existing one at Rahuri, are expected to be up and running in 18-24 months.

The agriculture and food processing ministries have reached out to the state to build these units. National agricultural cooperatives such as the National Agricultural Cooperative Marketing Federation of India (Nafed) and the National Co-operative Consumers' Federation of India (NCCF) will gather onion and despatch to these units, the official cited above said.

Please see: Barc to help preserve onion stocks

“Both these ministries will provide financial assistance to create the irradiation facilities and corresponding cold storage under the PPP mode so that private players can operate the same sustainably," he added.

The agriculture, consumer affairs, and food processing industries ministries did not immediately reply to queries.

Soothe the supply chain

The units will be set up along with the state government as public-private partnerships. The move is expected to soothe the onion supply chain which sees losses of as much as 10,000 crore every rabi season, and aid the government's procurement plans.

Maharashtra cultivates 43% of India's onion, followed by Madhya Pradesh (15%), Karnataka (9%) and Gujarat (9%). The move comes after the government lifted the ban on onion exports but slapped a 40% export tariff and $550 per tonne minimum export price earlier this month.

Also read: An export ban didn't cool onion prices. Now what?

The plan follows an initial trial in association with the Bhabha Atomic Research Centre (Barc) for 5,000 tonnes of onion that showed irradiation boosts storage period till seven-and-a-half months, compared to the typical cold storage period of around four months. 

The trial also showed that the recovery of Grade A onion has been nearly 84%, as opposed to 56% when stored in typical onion storage or kandachawl.

This year, the government plans to build an onion buffer of 500,000 tonnes, aiming to check price volatility. The buffer is built by procuring onions from rabi harvest for release in major consumption centres during the lean season.

India has two harvest seasons, with rabi fetching 65% of the total onion output. Rabi onion is harvested in April-June and stored for release, until the kharif variety hits the market in October-November.

Also read: India lifts ban on onion exports, imposes minimum export price

“The other reason behind the plan is that most of the irradiation facilities are directed towards food products with high remuneration like dry fruits, spices and packed food products; hence, establishing exclusive irradiation facilities for onion will promote usage of the irradiation technology," the official said.

Gamma rays: tried and tested

India has 28 gamma irradiation food processing plants, including five government-owned, used for different perishable crops such as potato, onion, tomato, mango, broccoli, cereal, pulses, spices, dehydrated fruits and ready-to-eat food. The new facilities, however, will only be dedicated to onion irradiation, the official clarified.

A pilot study on using low-dosage irradiation storage for onion on trial basis at Rahuri has also been proposed to understand the viability, feasibility and economics, the official added. The government may also outline protocols and standards for the storage and transportation, and setting up irradiation facilities at prime consuming areas.

Also read: Onion prices are already high, and there's more bad news

“We need to consider various factors such as purchase price, unloading charges, grading, transportation charges, etc. to calculate the total cost. A cost-benefit analysis has been done, and after the first trial, we can estimate the cost to be 38,283 per tonne, higher than 36,786 a tonne if put under chawl storage," the official said when asked about the financial burden.

According to a 2022 study by NABARD, post-harvest losses in vegetables are estimated to be between 4.8% to 11.6%. “Post harvest losses tend to not only impact farmer incomes but can also add on to price fluctuations in perishables by reducing supply," said Sakshi Gupta, principal economist, HDFC Bank.


Catch all the Business News, Market News, Breaking News Events and Latest News Updates on Live Mint. Download The Mint News App to get Daily Market Updates.