Active Packaging
Multisorb FreshPax® technology ensures products maintain quality and shelf-stability, creating a more appealing, palatable product for consumers - more packager profit
Active food packaging systems are enabling soldiers in the field to enjoy a larger variety of foods, such as barbeque chicken sandwiches, waffles, Combos, and M&M cookies. And coming soon is the classic peanut butter and jelly sandwich.
"Active packaging," sometimes referred to as interactive or "smart" packaging, may be an actual package structure or an adjunct, such as a sachet or patch containing a responsive chemical or physical agent. Oxygen scavenging is one class of widely used active packaging technology, for example, whereby iron-based pouches or sachets are inserted into individual food packages to retard oxidation and spoilage. Oxygen is a major factor in food product degradation, which is of concern especially for a military ration, which may not reach its ultimate consumer until one to two years after its date-of-pack. Oxygen scavengers provide maximum preservation of original flavor, color and texture, which is important to military and civilian consumers alike.
The use of active packaging helped influence menu expansion of the Meal, Ready-to-Eat (MRE), now the standard individual combat ration for the military, enabling a wide range of food options contained in multi-laminate, flexible polymeric pouches. In the early 1980's, the MRE began to replace the C-rations packed in metal cans.
Active packaging systems provide more than just an inert barrier to the outside world, but actually create a new interactive environment inside the package or pouch - removing undesirable components and adding desirable ones. Food quality is preserved by modifying the inner atmosphere to very low residual oxygen retarding the growth of spoilage bacteria and mold, biochemical and enzymatic degradation, and survival of insect larvae, while eliminating the need for food additives such as BHA, BHT and sorbates.
"Food interactions within the package are dynamic and so the atmosphere inside must be controlled in an interactive, responsive manner as well," says Richard Burke, of Multisorb Technologies, Inc. of Buffalo. NY
"A big breakthrough was the development of intermediate-moisture bread for the military," he says. "This enables the use of oxygen scavenger sachets with pouch sandwich-type meals, in addition to use with the bread and crackers."
Multisorb scientists have worked with the Defense Department's Soldier Systems Center in Natick, Massachusetts since the 1990's to find ways to provide mobile, high quality rations to soldiers stationed throughout the globe. The company is currently the only United States-based supplier of this technology to the military and holds a patented oxygen scavenger process known as FreshPax®, which protects packaged foods against loss of quality due to spoilage.
The basis of the technology is to remove intrapackage oxygen using absorption or "scavenging" deoxidizers, which are comprised of ferrous iron powder sealed inside small gas- and moisture- permeable pouches or "sachets." These sachets chemically absorb free oxygen inside the package to form a stable ferric oxide, safely maintaining the quality and shelf life of packaged oxygen-sensitive foods.
This shelf stability is critical because the military requires that foods be stable for a minimum of three years without refrigeration at 80° F and for six months at 100° F. Active packaging also makes logistics and storage easier, as it is well suited for worldwide environmental extremes, from deserts to tropical environments.
Oxygen scavengers can reduce the amount of oxygen in a package to less than 0.01 percent, as compared to traditional preservation methods such as gas flushing and vacuum packing, which reduce headspace oxygen to only about 0.50 percent. Active packaging can be used in conjunction with these standard methods, however, to achieve specific results.
In the military's Meal, Ready-to-Eat ration, oxygen scavenger sachets are sealed within - individual ration packages, making possible a variety of shelf stable bakery products and snack items. These include pound cakes, white bread, hamburger buns, waffles and snacks like chow mein noodles, peanut butter crackers, and chocolate chip cookies.
The peanut butter and jelly sandwich presents a particularly tricky problem because during storage, the peanut butter becomes crumbly, and the bread loses moisture and becomes very firm. However, formulation and processing procedures are currently being modified to overcome these problems.
According to physical scientist Lauri Kline, Project Leader in Active Packaging at the Natick Soldier Center, this desired pocket sandwich is currently under development for inclusion in the MRE, and should be available to military personnel within the next few years.
Kline went on to say that the science of active packaging has contributed to troop morale through the ability to expand food options for our troops. She said that the military now has the ability to offer popular commercial items. These familiar dessert-type and snack items are over-wrapped with conventional flexible packaging materials to provide soldiers with products that they would find in the stores at home everyday.
American-made, ferrous-based oxygen scavenger sachets were first introduced in the United States by Multisorb in 1984. These in-package inserts have capacities ranging from 20 to 2,000 cc of oxygen and are of two types: "self-working" sachets, which contain moisture and start their oxygen absorption process when exposed to air, and "moisture-dependent" sachets, which contain no moisture but extract it from the in-package atmosphere.
Meanwhile, in the battle for consumer attention in store aisles, this same active packaging technology is used to provide shoppers with packaged meats and snack products that have enhanced eye appeal and that stay fresher in terms of taste, color and nutritional value.
Shoppers prefer to buy foods in transparent packaging, but the store display lights tend to discolor the meat items, particularly in the case of cured products. By removing oxygen through active packaging, meat product quality is retained for up to 21 days, an improvement over the usual seven days possible with older preservation methods. This approach also helps to eliminate chemical reactions that cause "refrigerator taste".
Although the upfront packaging cost is somewhat higher when applying active technology systems as compared to traditional methods, the payoff is greater in terms of quality retention, sale-ability and consumer satisfaction.
"There is a big consumer advantage to this technology," says Multisorb's Richard Burke. "Since eating is an emotional as well as a biological need, we are able to provide as rich an experience as possible under the most mobile, harshest of conditions."
