New packaging film structures with new steam valve technology are delivering powerful business benefits to producers of home-cooked foods. The film-with-valve solutions protect home-heated meals from contaminants throughout the supply chain, make possible the use of higher temperature ingredients for the microwave and can provide a competitive advantage in the marketplace.

New film structures include multi-layer polyester laminates with a polypropylene sealant film. The heat-resistant polypropylene enables the overall structure to accommodate food ingredients that traditional sealant films, such as metallocene (mPE) and low-density polyethylene, find too hot to handle. What this means to food producers is that they can now add ingredients that become overly hot to their home-cooked meals with little risk of heat-related damage to the packaging film. Sauces are a case in point. The sugars present in most sauces heat to temperatures that could compromise conventional sealant films during the cooking process. The emergence of film structures with a polypropylene sealant now let producers add a tasty sauce to nearly any dish, with virtually no risk of damage to the packaging film.

Essential to the overall packaging design, and to the prevention of contaminants entering the food product, are Flexis™ steam valves, a recent technology development by Avery Dennison. The valves provide a hermetic seal when applied over a pre-cut hole in the packaging. The valves can be produced in a variety of configurations for both microwave and oven cooking. In operation, they control the amount of moisture that escapes the package at predetermined cooking temperatures.

Some flexible packaging companies, such as Printpack Inc., have in-house engineering resources and are expert at designing new film structures, complete with steam valves, that meet the sealant and steaming requirements of individual meals.

Steam valve configurations likewise may vary from dish to dish. On a rice, veggie and protein meal, the flexible packager might select valves having a floret baffle design, which helps maintain higher pressure and retain an additional percentage of moisture inside the package. For a pasta, chicken and vegetable dish, the packager might specify an “X” baffle configuration, which releases a bit more moisture from the enclosure and thereby thickens the meal’s sauce.

Steam valve specifications also can be made to speed the meal’s cooking time and to facilitate thoroughness of cooking. Properly designed steam valve baffles help ensure evenness of heating throughout the meal, which eliminates cold spots even with sauce, fish and rice or other particularly challenging-to-heat home-cooked meals.

Food manufacturers that employ vertical form, fill and seal (VFFS) machines may need to adjust their sealing temperatures to accommodate new packaging film structures equipped with steam valve technology. However, the resulting package will deliver superior performance in the microwave and the oven. And when competing for consumer satisfaction, performance is critical.

Consumers seeking dining convenience also consider price and quality when making a dining decision. To stay at home or to step out? Home-cooked meals featuring delicious sauces that complement handsomely prepared meats, fish and vegetables may convince consumers that the better value is eating in. The factors of convenience, time-savings and price can influence the consumer’s decision to eat at home. Quality will depend significantly on how well a meal cooks in a consumer’s home. Steam valve designs can accommodate each SKU in a food producer’s home-cooked product line and help make the taste, appearance and overall presentation of a home-heated meal the more attractive dining option.

Nick Greco can be reached at