Each element of the MAP equation -- gas, equipment and film suppliers -- must work in harmony to create a successful MAP package. Michael Thaler, director of marketing at Air Liquide America (Houston, TX), notes that many factors must be examined before a food company implements a MAP system. quot;Generally, we take a look at the entire system from the receipt of the raw ingredients that [are] used to make the product, all the way through the processing, packaging, the gases and holding at the storage facility," Thaler said.
According to Thaler, food companies should focus on the quality of the food product before the length of its shelf life. "Instead of long shelf life, [Air Liquide] tries to see how much of the original flavor and original quality we can retain by the time the consumer eats the food product. It's not a question of how long does it last before you throw it away -- it's does it taste like it was just produced at the plant or does it taste like it's been sitting in storage somewhere for a month," said Thaler.
To achieve this extended shelf life, Marsh agrees that using a "combined technology" approach to MAP packaging creates more barriers to microbial growth. "Consumers want less additives and preservatives in their foods. Ultimately, this provides a challenge for any food manufacturer who wants to provide this type of product with an extended shelf life. We always keep the hurdles of spoilage in the back of our minds," Marsh said.
DeLuca, Inc. began manufacturing their Ed & Joan DeLuca brand of refrigerated entrees with a 30-day shelf life nearly ten years ago. "In all of our years of both sourcing and working with packaging materials that have the barrier properties necessary to achieve our extended shelf life, we have found it necessary to work with manufacturers to create custom specifications in order to produce the desired results," said Jeffrey L. Zwicker, president and CEO of DeLuca, Inc. According to Zwicker, MAP technology was the last "hurdle" needed in the packaging process to achieve the 30-day shelf life.
DeLuca has made product safety a top priority in order to deliver fresh foods with minimal processing. "We recognized a long time ago, that in order to fulfill our vision of a national brand, we would need extended shelf life for manufacturing and distribution logistics," said Zwicker. "Further, we did not want to have to use preservatives to achieve our goals."
Assuring product safety throughout the entire cold chain is also paramount to success. "The greatest percentage of our products are shipped directly to our customers' warehouses and therefore are not as subject to potential abuse as perhaps other methods," said Zwicker. The company also monitors the temperature of the showcases where its products are sold as often as possible. "At the end of the day, you must market a superior product to make it in the fresh food arena. Consumer expectations are much higher than that of a frozen entree, and fresh costs more, so we need to deliver on that expectation in order to be successful," said Zwicker.
DeLuca, recently acquired by Perdue Farms Inc., has introduced
a line of Perdue chicken-based entrees co-branded with the Ed & Joan DeLuca brand. The HMR entrees include Chicken a la king with Egg Noodles, Chunky Chicken Parmigiana with Rotini, Chicken Cacciatore over Linguine and Chicken Lasagna.
According to Green, because most consumers do not understand the difference between pasteurized milk and ultra pasteurized milk, ESL technology is driven more by the distribution base rather than the consumer. "What [consumers] like to see is the fact that [milk] has the longest shelf life that's possible. Once you open the package, it lasts no longer than regular milk -- seven days. So really the benefit is prior to opening the package and the ability to reach out to a wider geographical distribution by going through warehouses or alternate and secondary distribution channels," said Green.
This extended shelf life does not come without cost, says Green. "The extended shelf life improves overall operating efficiencies in terms of plant scheduling and inventory management, but there's the cost of processing that you have to incur because we take it to a much higher temperature. So you pay a premium for it, but at the same time, it is lower cost distribution," said Green.
Another technology currently being used to extend the life of packaged dairy foods is a carbon dioxide injection process that maintains the freshness, consistency and taste of dairy products. This process can extend the shelf life of several dairy products as much as 50 to 100 percent. According to Walter Sienkiewicz, manager of commercial development at Praxair's food segment division in Chicago, there are currently up to 30 processors that are using carbon dioxide in cottage cheese for shelf life extension. Praxair has also used carbon dioxide injection to extend the shelf life for other dairy items such as ice cream mixes, ricotta cheese and yogurt.
Sienkiewicz sees the benefits of extended shelf life in greater
operating efficiencies, expanded distribution and increased savings. "One processor used to be a very small, regional player with their dairy product and now they're shipping it across 12 to 15 states because of the added shelf life [using carbon dioxide]," said Sienkiewicz. According to Sienkiewicz, longer shelf life also leads to less product changeover over a period of time for food processors, translating into longer product runs and increased economic savings.
California-based food processor Apio uses Intellipac breathable membranes to help provide a 14-day refrigerated shelf life for its "Value Fresh" brand party tray that contains six pounds of fresh pre-cut vegetables and prepackaged dip. The multi-compartment tray, currently sold in club stores, is the first use of Intellipac technology in rigid food containers, and is the first and only MAP party tray known in the market place, according to Lynn Biggs, Landec's director of sales and marketing. Intellipac membranes are also used for Apio's bagged broccoli and cauliflower vegetable mix as part of its "Eat Smart" retail bulk bin program and is sold as an individual bag in club stores as well.
There are also two new invisible films that remove residual oxygen from modified atmosphere packaging without changing the look or feel of the existing packaging. A new low-oxygen packaging system called OS1000 from Cryovac North America (Duncan, SC), reduces oxygen levels in MAP applications to "parts per million" -- essentially eliminating residual oxygen levels in four to ten days, enhancing product shelf life. The film begins to scavenge only when activated by Cryovac's ultraviolet triggering unit installed on the processor's packaging line. Because it is activated independently of the product in the package, the film will work with wet or dry food products.
Amoco Chemical's (Chicago, IL) Amosorb oxygen scavenger is another transparent film that can greatly enhance shelf life. By using Amosorb 3000 copolyester as a core layer in a multilayer polyester container, shelf life can be extended for items such as fruit juices, tomato-based products, ready-to-drink teas and beer.