From time immemorial man – the hunter, man – the forager, man – the farmer has been obsessed with the preservation of food be it for the proverbial rainy day, for Noah’s ark or for the long, harsh winters. Make hay while the sun shines and then look for ways to stock that hay. Gone are the days of grandma’s home remedies of sun drying and vinegar, salting and pickling in large ceramic pots. The new age mantra is no longer defined by the limits of storage but prides itself on preservation: frozen, deep frozen, canned, Ziplocs, freeze dried, vacuum dried, powdered and so on so forth.
Then came the brain wave of GM (Genetically Modified) crops. So it was all about cutting out the “will spoil soon” gene and replacing it with the “longer shelf life” gene. A few placards and protest marches later that too fizzled out. The mass outcry from humanity (which is another story) still leaves us eons away from making them a daily necessity.
Hence we fell back on conventional methods to improve storage. Then one wise prof said, “Let’s go nano”. Yes we already have the car but here at IIT madras we can think of other interesting things to do on a 10-9 scale.
Dr Chandra’s (BT) and Dr Natarajan’s (Physics) research groups are focused on a highly innovative technology which could revolutionize the food packaging industry. The major issues in maintaining the quality of packaged food are oxygen diffusion, moisture control and microorganisms.
Nanocomposite materials offer improved functionality over traditional composites and polymers in terms of barrier properties, strength, elasticity and optical clarity. Nanocomposites can be functionalized to include other characteristics, for example, antimicrobial properties, visual indicators of food freshness, means of identification and authentication, and approaches to augment the ease of tracking. Nanoclay incorporated nylon composites have high barrier properties for gases, moisture and microorganisms passage. Grad students Anshika and Anant are working on developing electrospun nanomembranes for packaging of food products like bread, chips, savories, butter, biscuits etc, to increase their shelf life. They define shelf life parameters by measuring moisture absorption, lipid peroxidation and microbial growth.
Their work shows great promise for nano-coated packets as an intelligent and smart food packaging system and can be made cost effective when compared to other plastic packaging. It can be applied as barrier packaging (for fresh foods), packaging for the internal environment (active packaging), food quality (intelligent packaging), monitoring and authentication tags (smart packaging).
With a booming commercial market on the global frontier, such a technology would definitely benefit in waste reduction, convenience packaging, traceability and tamper indication, increase food safety and quality, identification of items and stock to support the effective delivery of food to the consumer.
That day shall not be far when nano coated grapes and nano wrapped sandwiches find their way into your shopping carts. Now if only one could figure out how to nano protect them from our mischievous monkeys?
(With inputs from Anshika Agarwal, Grad Student, BT)
Written by Ranjini Balan, Correspondent