Tribune News Service
Chandigarh, August 9
Indian scientists have developed a composite paper made of carbon that is loaded with preservatives, which can be used as a wrapper to help extend the shelf life of fruits. This product can benefit the farmers and food industry and is also ecologically friendly.
Unlike the present preservative dipping technology, where the preservatives are absorbed by the fruit, causing chronic toxicity to the consumers; the graphene oxide carbon wrapper releases the preservative only when needed. The wrapper can be reused, which is not possible with the present technology.
Fruits are highly perishable and about 50 per cent of the produce gets wasted, causing huge losses. Conventional preservation relies on coating the fruits with preservatives like resin, wax, or edible polymer, which can result in serious health problems.
To address this problem, a team of researchers led by Dr PS Vijayakumar from the Institute of Nano Science and Technology, Mohali, looked for an alternative, that could be generated from waste and would not lead to adsorption of preservatives in the fruit.
The activated graphene oxide molecules were loaded with preservatives. This high preservative-loaded graphene oxide, when cast into a paper used to wrap fruit, ensures that the fruit is not contaminated with excess toxic preservatives.
When the fruit over-ripens or gets infested by pathogens, the increase in the level of acidity triggers the release of the preservatives. Otherwise, the preservative stays with the carbon wrapper. In the fruit dipping method, the preservative will be lost along with the fruit, whereas the wrapper can be re-used after the consumption of the fruit for the preservation of the next batch of fruits.
To develop this non-toxic and reusable wrapping paper, the team allowed the carbon matrix to incubate with the preservative. After the incubation for 24 hours at room temperature, the resultant was washed several times to remove the extra preservatives. Finally, this carbon-preservative composite was cast into paper.
“Already waste-derived carbon materials are known to harbour a huge amount of organic molecule loading. Hence the preservative-loaded carbon has been prepared and cast into paper for fruit preservation. Increasing the capacity of carbon to hold organic molecules helped us to develop this product,” Dr Vijayakumar said.
The production of this graphene fruit wrapper requires only the carbon produced from the heating of biomass, hence it will also benefit biomass consumption and aid employment generation.