Food-wrapping films made from waste cucumber peels
doi:10.1038/nindia.2020.178 Published online 25 November 2020
Cellulose nanocrystals extracted from discarded cucumber peels are potentially useful for making nanofillers, a study reveals1. Such nanofillers could be used for producing food-wrapping biocomposite film, says a team of researchers from the Indian Institute of Technology in Kharagpur, India.
These films, the researchers say, will be biodegradable and biocompatible. The nanocrystals could also be used for making hydrogels, paper, coating additives and optically transparent films.
According to previous studies, fruit peels are rich in cellulose, which has potential applications in food-packaging materials. However, none of the studies had explored the potential of cucumber peels, which are also rich in cellulose.
To find out, the IIT scientists extracted cellulose from dried and powdered cucumber peels. They then converted the cellulose to cellulose nanocrystals using specific chemicals.
The researchers found that the cellulose content in cucumber peels is higher than that of the banana, orange and mango peels. The cucumber peels also yield more cellulose nanocrystals than the other fruit peels. Analyses revealed that the nanocrystals have a high surface to volume ratio. These crystals are also light-weight and can withstand temperatures of up to 200 degree Celsius.
Since the nanocrystals are non-toxic, they will be useful for making drug-delivery systems, sutures and stents, the researchers say.
1. Prasanna, N. S. et al. Isolation and characterization of cellulose nanocrystals from Cucumis sativus peels. Carbohydr. Polymer. 247, 116706 (2020)