Silk fibroin coating keeps food fresh without refrigeration

Signal of change / Silk fibroin coating keeps food fresh without refrigeration

By Chiam Dajian / 02 Nov 2016

The FAO suggests that up to 50% of fruits and vegetables are lost along supply chains, mostly due to poor handling, storage and transport of perishable goods.

Through diffusion of gases, cell respiration, and microbial contamination, perishable goods often suffer from fungal decay, colour change, loss of firmness and poor flavour. Scientists have tried a variety of methods to extend shelf life, including cryopreservation, chemical fungicides, modified atmosphere packaging, and other kinds of edible coatings.

In May, tests conducted by Tufts University biomedical engineers have shown the potential of silk fibroin, a natural, edible and odourless biomaterial potentially useful for a number of high-tech applications, to keep perishable foods fresh without refrigeration.

So what?

The silk fibroin coating represents an innovation in the application of biotechnology to address problems of postharvest losses.

Many existing methods to retain shelf-life and preserve fruits and vegetables through the supply chain, including spraying them with chemical fungicides, are not very palatable for consumers that are increasingly aware and conscious of how their food reaches them. Other methods require the modification of the atmosphere around the fruit, including an additional layer of packaging, which increases waste.

The silk fibroin coating will likely be viewed as a healthier and more sustainable alternative, and potentially highly marketable for big agribusiness companies trying to remake their image.

Many questions remain around the applicability of this nascent technology, mostly regarding its price point and practical application. While highly-mechanized industrial strawberry farms in developed countries might be able to benefit from its use, smallholder farmers in developing countries, those who most suffer the cost burden of food losses, would likely not be able to access or afford it. Even if they could, what kind of infrastructure and training would be required for it to be “operational”?

At small scales, it’s likely the benefit of increased shelf life outweigh the additional cost of a new input to production for them. 

This signal of change was spotted as part of Disrupting Food Logistics, a multi-stakeholder collaborative endeavour to build the sustainable zero-waste food supply chains of the future, drawing on innovations from across the globe.

For more information, please read the Call to Action and reach out to Gwyneth Fries, Senior Sustainability Advisor at Forum for the Future at


What might the implications of this be? What related signals of change have you seen?

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