A French packaging invention could give a much longer shelf-life to bread, sandwiches, pizzas and patisserie.
In this double-wall system, the product is housed in an inner micro-perforated layer, while the outer layer contains a modified atmosphere. Inventor Joël Gourlain explains: "The water molecules contained in the ingredients will always move, and are naturally accelerated when the temperature becomes higher. The water flow moves from the inner perforated barrier to the outer, where it is trapped." By-product gases such as ethylene are isolated in the same way.
According to Gourlain, the patented system will extend fresh sandwich shelf-life to 10 or even 14 days. Pre-baked bread, which is then baked off by the end-user, can be transported at ambient temperatures using this system, he claims, giving a shelf-life of up to five weeks.
The technology is already being trialled by a French user of thermoformed packaging for sandwiches, and Gourlain says that other versions could be used in flexible packs such as flow-wraps.