IIT team develops edible coatings to extend shelf life of fruits, vegetables

Guwahati, Aug 29

Amid tonnes of crop waste in the country, a team of researchers at the Indian Institute of Technology (IIT), Guwahati, has developed an edible coating material to extend the shelf-life of fruits and vegetables. This coating material, which will prevent wastage, was tested on vegetables and fruits such as potatoes, tomatoes, green chillies, strawberries, Khasi mandarins, apples, pineapples, and Kiwi fruits and was found to keep these fresh for nearly two months.

"According to the Indian Council of Agricultural Research, between 4.6 and 15.9 per cent of fruits and vegetables go waste post-harvest, partly due to poor storage conditions. In fact, post-harvest loss in certain produce items like potatoes, onions and tomatoes could be as high as 19 per cent, which results in high prices for this highly consumed commodity," researcher Vimal Katiyar, Professor at the institute, said in a statement.

The team said they believe that their development could help the country meet the Sustainable Development Goal (SDG) target 12.3, which aims to reduce food losses along the production and supply chains, including post-harvest losses.

The team used a mix of micro-algae extract and polysaccharides to produce protective, edible films for coating vegetables and fruits. The marine microalgae called Dunaliella tertiolecta is known for its antioxidant properties and has various bioactive compounds such as carotenoids, proteins, and polysaccharides.

It is also used as a source of algal oil, which is used as a non-animal source of omega-3 fatty acid and is considered as a source of biofuel. After the oil is extracted, the residue is usually discarded.

The team used extracts from this residue in formulating their film in combination with chitosan, a carbohydrate, which has antimicrobial and antifungal properties and can be made into an edible film.

The properties of films with varying algal extract contents were analysed and compared with controls. The fabricated edible films displayed superior antioxidant activity, total phenolic content, water vapor barrier property, thermal stability, and mechanical strength. They also had excellent UV-Vis light-blocking properties.

Further, multiple other customised edible coating formulations are developed to enhance the product's shelf-life based on the requirement.

--IANS