Food packaging is set to become even more functional in the future. If current prototypes are anything to go by it might not be long before packaging is edible or that it is able to warn us when it needs refrigerating, claims a report in the Seattle Times.
To many, packaging is just the annoying bit that you have to often tussle with before you can begin your feast. Nonetheless the science of food packaging hides a host of considerations essential to convenience, food safety, freshness and all-important taste.
Even as they use them, most consumers don't really understand packaging technology, said Bob Testin, a professor emeritus of packaging science at Clemson University, South Carolina.
For example, many people think the plastic bags that preserve salad greens "breathe" through holes. In fact, they're made of a special film that creates a different atmosphere inside the bag, restricting the flow of oxygen in and carbon dioxide out.
This "modified atmosphere" packaging is also used with products such as packaged meat and fresh pasta. In fact many innovations repackage existing products to offer more convenience.
"Food on the go" that fits into car cup holders now includes snacks in upright containers and flavoured milk in slim plastic bottles.
Another packaging trend encourages materials that decompose, recycle easily or use up less landfill space.
"The first principle of environmentally friendly packaging is to use less stuff," Testin said. "The ideal packaging weighs nothing and takes up zero volume." The US Environmental Protection Agency says food packaging accounts for 1.8 million tons of waste dumped into landfills every year.
Companies such as EarthShell have developed biodegradable food packaging made primarily of limestone and potato starch. McDonald's signed on to buy Big Mac sandwich containers made of the material and Wal-Mart sells EarthShell plates, for example.
Another innovation consumers can expect to see on future grocery shelves includes packaging that raises the alarm if conditions, such as too-warm temperatures over a period of time, have or could lead to premature spoilage of items such as seafood, dairy and meats.
Misuse could include anything from a refrigerator that should be cooler (most refrigerators aren't kept at the recommended 38 to 40 degrees) to a product that is left out on the counter too long, Testin said.
"We can control conditions at the food plant and to some extent at the supermarket, but we can't control what the consumer does," said Testin, who expects the technology to be used on individual packaging within five years.
A further development would allow the combat of common meat-borne bacteria with anti-microbial plastic film that slows the growth of micro-organisms. Film developed by Clemson scientists contains lysozome and nisin, two natural proteins that inhibit bacterial growth.
Anti-microbial film could also extend the shelf life of other perishables such as shredded cheese, for example.
The Southwest Research Institute in San Antonio developed polymer films and coatings that generate a controlled amount of chlorine dioxide over time, inhibiting the growth of mould and bacteria in packaged foods.
Tara McHugh, a scientist with the US Department of Agriculture's Agricultural Research Service in California created an edible film from pureed fruits and vegetables.
The film, which retains the colour and concentrated flavour of the fruit or vegetable, could be used to cover food, such as plastic wrap does now. A tomato film could go over a bowl of spaghetti, for example; after heating, the film could be stirred in as part of the sauce. Or a peach film around a ham could create a glaze when cooked.
McHugh says she hopes the edible wrap will help people meet nutritional guidelines for eating more fruits and veggies as well as reduce waste. She said a company is working on producing large rolls of film, which she expects to be ready for the market by autumn.
On the condiment aisle, shoppers can expect to see Heinz's new upside-down ketchup bottle topped - or bottomed, rather - with a patented silicone valve and stay-clean cap this summer.
Meanwhile, French's new patented mustard bottle, which hit shelves this spring, features a diaphragm at the top of the hour-glass bottle to allow even distribution. This cuts out that initial watery spurt and draws excess mustard back into the bottle.