We put a lot of faith in the food we buy. Every time we open up a jar of pickles, a bag of potato chips or a can of soda, we trust that that product will be safe and of a high quality. The package that food is in has a great impact on that safety and quality. And you may not realize there is actual science behind food packaging, which is quite intricate and complex.
This week on Take Care, Dr. Joesph Hotchkiss talks about the science of food packaging. Hotchkiss is the director of the School of Packaging and the Center for Packaging Innovation and Sustainability at Michigan State University. He was once a science advisor in the Food and Drug Administration, and holds a Ph.D. in food chemistry.
Click 'Read More' to hear our interview with Dr. Joseph Hotchkiss.
Effective food packaging is important to protect food against many things.
“Everything from oxygen, for example, which can deteriorate a lot of food, to changes in moisture content, microorganisms, including mold and things that would deteriorate food, and loss of color,” says Hotchkiss. “There’s a whole range of things that you really have to look at each individual food and then develop a packaging system which really attacks that individual vector.”
In other words, each package is distinctly unique to the contents it holds, and the goal of that package.
“We always think of food processing and packaging as a way to save nutrients for use at any time you want. And we kind of forget about that because it’s a relatively new thing in human history. For much of human history you only ate things when they were freshly available, and now you have every kind of food at any time you want,” says Hotchkiss.
According to Hotchkiss, food producers and scientists consider many different things when determining which package is the best fit for a product. One issue is balancing the practicality of the package with the attractiveness of the package, as that can directly affect sales of the product. Another is the compatibility between the product and the package, and how they interact with each other.
“Canned products can interact with the can, as a matter of fact if the can is not protected from the food, the food can literally eat a hole in the side of the can. There are cases where parts of the package transferred to the food, and so there lots and lots of food packaging interactions, many of which have implications for product safety, product quality, shelf life and so forth,” Hotchkiss says.
Consumers often look at an "expiration date" or a "best by date" as a definite date at which the product can no longer be consumed. Hotchkiss says otherwise.
“In most cases that date is actually put on there by the manufacturer simply on a quality basis. In other words, the manufacturer makes the decision, ‘you know what, we don’t think people should consume our products simply for quality reasons after this date.’ I suppose you could argue for some kind of safety issues, it’s kind of a guideline, but they are not really set there for safety. Food products that are offered for sale have to be safe, regardless of what the date on them is or is not on there,” he says.
With many innovations being made in the world of food packaging, one method in particular, active packaging, has become more and more popular recently. Hotchkiss says active packaging directly helps keep the product fresh. An example of this is how precut salad is packaged.
“What has allowed that to happen is in part the packaging system, which actually in many cases contains tiny, tiny microscopic holes in it that allow that lettuce to breathe at a certain rate to produce the maximum shelf life and quality of that precut lettuce product. So that is active, it is actively helping the lettuce last longer,” he says.