Researchers in New Zealand have discovered potential anti-fungal properties in harakeke, or native flax, that could see the fibres used in food packaging but admitted more funding is need to continue the research.
The researchers pointed to benefits including extended shelf life, transportability and export of vulnerable produce and said it could be used in the packaging of fresh food that spoils easily.
The team found harakeke has a high content of a type of sugar polymer called hemi-cellulose, which results in the production of acetic acid causing deterioration of fibres.
The fibres also produce coumarin, a fragrant chemical compound that can is found in the aroma of freshly cut grass.
Why use harakeke?
Dr Gerald Smith, Victoria's associate professor of chemistry, told FoodProductionDaily.com the harakeke fibres are a sustainable, renewable natural resource.
“Using these fibres as packaging would provide a new primary industry based on harvesting a rapidly growing plant (replacing a previous commercial crop used as cordage/rope).
“This type of material has another important advantage compared with synthetic packaging fibres/materials - it is biodegradable.
“We believe sufficient quantities of this rapidly-growing plant could be cultivated in land unsuitable for arable farming to meet the demand for the fibre as a packaging material.”
Smith believes the research holds promise for reviving New Zealand’s flax industry, which was a significant earner until the advent of synthetic fibres that use non-renewable material resources.
The research began to find ways of stabilising the flax fibres in old Māori cloaks, which become brittle after exposure to light and humidity over time.
He said the team found a number of anti-fungal chemicals to be naturally occurring in harakeke fibres.
“Research to date has shown that harakeke fibres contain both volatile and non-volatile anti-fungal chemicals and the rate of release of some of these agents can be modified by treatment of the fibres with non-toxic substances.
“No toxic or synthetic substances would be introduced in the preparation of harakeke fibre packaging.”
Future research steps
Smith added the preliminary research has shown that the fibres have antifungal properties that could be enhanced for use in food packaging but a lack of funding has halted any move to pursue the idea further.
“The main research challenge now is developing the stimulation and control of the release of active chemicals present in the fibres for efficacious antimicrobial activity under the temperature/humidity conditions encountered in the transportation and storage of horticultural products.
“This research would specifically quantify antimicrobial activity of the fibres under a range of environmental conditions and also determine empirical antifungal activity with respect to selected products infected with common air-borne fungi.”