Mustard seeds boost shelf-life

Mustard oil could help manufacturers improve the shelf-life of everything from bread to cheese, fruit and pet food without having to use modified atmosphere packaging, according to researchers at the Technical University of Denmark.

Professor Per Vaeggemose Nielsen from the university's centre for microbial biotechnology, said: "As the Japanese have known for years, mustard oil is a natural antimicrobial. Europeans have also used it in horseradish sauce, which is a preservative.

"It kills micro-organisms such as mould and yeast very efficiently by working in the gas phase inside the package. It's so effective, you can use it instead of gas flushing [modified atmosphere packaging]. You can also significantly reduce preservative use."

He added: "You can incorporate the oil into the packaging itself or incorporate it in a label that is applied to each package on the production line via a label dispenser, so no changes to the manufacturing process are required. The oil is activated by moisture in the food."

The packaging, which has been tested at a bakery in Denmark, was comparable in price to oxygen scavengers, he said. "But costs would obviously come down if this was done at scale. It's particularly effective in bags of food where you get humid hotspots."

While mustard oil was approved as a flavour in the EU, it would separately need to gain approval as a preservative if it were to be used in packaging as an antimicrobial, he said. "I'm putting together a dossier to try to ensure that it makes it onto the EU 'positive list' of approved additives."