Active packaging agents have limited shelf-life benefits

The impact on food and drink shelf-life of active agents inside packs is rarely accurately predictable, according to packaging supplier Sirane.

What’s more, with no dependable vapour-phase antifungal/antimicrobial agents available yet, the effects of many current options remain weak.

Efforts to successfully incorporate plant-derived antimicrobials and antibacterials into food packaging have gone on for at least 30 years, said Sirane md Simon Balderson, who worked with Cryovac in the 1980s.

“Once you’ve put garlic or carvacrol, for example, into the film, it’s likely to have to go through high-temperature processes and will have to stay active for a long time,” he pointed out.

Blending active compounds

Using coatings, as Sirane had done in the past, he said, made more sense than blending active compounds with the film polymer, since in a coating those compounds were only applied where they were required.

But coatings could negatively affect packaging performance, for example with heat sealing.

Sirane’s shelf-life-extending technology uses absorber pads as a vehicle for tailored blends of “natural bioflavonoids and organic acids”, understood to include “very effective antimicrobials and antifungals” such as potassium sorbate and sorbic acid.

“Our Dri-Fresh ABV pads, for fruit and vegetables, contain more antifungal agents, while ABM and ABS, for meat and fish respectively, are more on the anti-bacterial side,” said Balderson.

Fruit and vegetables

“If people are going to use a pad anyway, by definition you can impregnate it with the agent, which is more likely to stay there than a film coating.”

The safety of any compound is clearly the main priority, and the agents used by Sirane are relatively inexpensive. “The pad might cost around 1p, and the active component will add 10% or 20% to that cost,” he explained.

However, it is never easy to predict the effect on shelf-life of pads, he admitted. In part, this is to do with the limitations of aqueous-phase agents.