Researchers study nanoparticle-based polymers to extend the shelf life of foods and beverages

Non-chemical packaging is being developed to extend the shelf life and safety of foods and beverages. However, there are concerns about moving potentially harmful substances, such as silver nanoparticles, from these types of containers to edible products.

Now, researchers report Applied Materials & ACS Interface show that silver rooted in non-microbial plastics can leave the material and form nanoparticles in food and beverages, especially in sweet and sugary ones.

Some polymers containing nanoparticles or nanocomposites can become microorganisms that are responsible for food and beverage damage and foodborne illness. Although these polymers are not currently approved for packaging use in the U.S., researchers are studying different types of nanoparticle-based polymers that can be incorporated into vessels. in the future.

Previous studies have shown that some of these polymers can dissolve nanoparticles, dispersed fertilizers, and ions into water-based food samples, but so far, little is known about what packaging may interact. with real foods and drinks.

Some sugar compounds, which are common food ingredients, can turn silver ions into potentially harmful nanoparticles, which in turn can be absorbed by humans.

So Timothy Duncan and his colleagues wanted to see how the complex ingredients in sugary foods and beverages influenced the formation of these nanoparticles, both when exposed directly to loose silver and when they are stored inside a packet with money.

To test if silver accumulations are dispersed in complex edible mixtures, the researchers spun money into beer foods and beverages, including naturally and artificially sweetened solutions, soda, milk, juice, yogurt, and starch-based ginger.

The mixtures were incubated at 104 F for 10 days or more, mimicking long-term storage in packaging material. Nanostructures were detected at two silver assemblages, one at the scale expected from polymer-contact smelting, and the other at high impractical density, allowing the team to monitor nanoparticle formation by eye. .

Liquids with starch, citrates, and fats contained the majority of nanoparticles, and initially acidic liquids formed silver aggregates that were later dispersed. In another experiment, the researchers kept water and two liters of sugar in small packets of silver-rich polyethylene polymer at 104 F for 15 days.

The first dissolved silver was released from the surface of the polymer, but only the sugar solutions further melted and formed nanoparticles.

The researchers concluded that it is possible to reveal a silver nanoparticle diet from sweet foods and beverages packaged in non-microbial products under the conditions normal for long-term storage.