As scrutiny over food packaging intensifies, the manufacturing and associated industries continue to press operations to ensure safety procedures are in place.

Today’s food manufacturers have at least two primary goals. The first is making products that satisfy the ever increasing demand for food taste, quality and convenience. The second is ensuring these products are safe. Even the best tasting product will be a disaster if it is contaminated by the very package that is designed to protect it.

Food manufacturers depend on their packaging suppliers to cover the basics like providing outer wraps that look attractive and pop on shelf. In so doing, these suppliers must also meet FDA standards for food safety. These governmental standards exist to prevent harmful components in the package from migrating to the food product.

The ultimate responsibility for safe packaging, however, is up to the converters, who must understand the issues of migration and how best to prevent migration from occurring.

Food contamination continues to be a problem in the U.S. and abroad, and the results are costly. Contaminated product must be pulled from the shelf, public apologies need to be made, detailed articles outlining contamination details are published in national newspapers, and chief executive officers of major corporations issue statements about what went wrong.

Just last year, 4-methylbenzophenone was found in breakfast cereal in Germany. In 2005, millions of liters of infant formula were recalled in four European countries because of the migration of a contaminant linked to isopropylthioxanthone (ITX) which, along with 4-methylbenzophenone, is commonly used as a photoinitiator in a number of UV-curable ink formulations.

The Need for Education

No manufacturer sets out to produce contaminated products, and yet it happens. The fact that it does indicates a lack of industry-wide understanding of the issues leading to migration and what can be done to prevent it.

Although governmental agencies can do their best to both understand and publish information critical for today’s manufacturers, it is the printer’s responsibility to ensure that its packages are not subjected to food contamination.

James Ford, senior chemist at Color Resolutions Int’l., works closely with converters to formulate inks and coatings to meet stringent food packaging specifications.

Defining Terms

The most common misunderstanding among printing manufacturers is in regard to the terms “direct” and “indirect” as they relate to inks used in food packaging. Direct food contact occurs when a printing ink on a surface actually touches the food inside the package. An example would be a coupon insert inside a box of cereal.

Inks can also be in indirect contact with food, as in the case of packaging for a bag of cookies. In this indirect case, the printing ink is on the outside of the package, not in direct contact with the food. Hence the plastic bag may serve as a functional barrier between the ink and the food.

For both the direct and indirect case, the FDA has specific regulations designed to limit the potential of harmful substances in the ink migrating to the food. The U.S. Government publishes a Code of Federal Regulations, which establishes guidelines for converters; the key is deciphering these regulations and knowing how to put them into practice.

In the case of direct food contact, such as the cereal in-box coupon, inks must be formulated with special components that are on the FDA’s GRAS (Generally Regarded as Safe) list or they must be in compliance with the FDA Indirect Food Additives Guidelines (21 CFR 170-189). The term the FDA uses, “Indirect Food Additive Guidelines,” likely causes significant confusion since this term refers to inks in direct food contact situations. Nonetheless, inks that are to be in direct contact with food must be comprised solely of components on the FDA’s approved list.

Surprisingly, the FDA does not regulate ink components for indirect food contact. This occurs when ink components that are not intended to be in contact with food accidentally are in contact because of migration through a barrier intended to keep them out. The federal regulations simply state that substances may not be transferred to food unless they are approved under the Food Additive Guidelines or are on the Food Contact Notification list.

Migration Regulation and Testing

Food and Drug Administration regulations cover migration in specific detail. Accidental migration into food products at very small levels is acceptable, but limited by the FDA, typically in terms of parts per billion on a weight to volume basis. Ink components that exhibit migration must meet testing specifications before being accepted as suitable for manufacturing.

When testing ink components for possible migration, the testing must be specific to the printing application. Testing under the exact production parameters (temperature, humidity, press speed, etc.) is critical, as inks will typically respond differently depending on the substrate and printing conditions. Migration tests must also simulate storage conditions as well as the conditions under which consumers prepare the food. Different testing methods will be used for a package that undergoes a cooking cycle (i.e. microwave popcorn) versus one that does not (i.e. a frozen bag of vegetables).

For a migration test to be successful, cooperation must occur not only between the ink supplier and the converter, but also between the ink supplier and the manufacturer of the ink components. Cooperation between the latter two is typically accomplished via a third party testing lab.

The primary reason for enlisting a third party is twofold: To identify all the chemical components that go into the ink, thereby validating the analytical test method, and to ensure that all possible migration issues are understood and quantified to meet FDA regulations.

Ultimately, it is the converter’s responsibility to ensure food safety. However, both the ink supplier and the ink component manufacturer play key roles. They not only need to provide the most accurate and up-to-date information to the printers, but must also be ready to pull out the red safety flag if a printer lacks the understanding and knowledge to assess whether their product is food-safe. In this case, the ink supplier should assist the converter in getting up to speed on all current regulations.

Getting It Right

But the story does not end here. Getting inks to be safe for food packaging is simply the price of entry. With the ever increasing demand for high-end graphics, safety has to coincide with efficient on-press performance. Ink suppliers must be able to meet these simultaneous and often conflicting demands.

Those working on the production of food packaging must have a full view of the entire process. Ensuring food packaging safety means partnering with all the suppliers involved, making sure everything about the package and its environment is understood, continually focusing on education, and using available published guidelines.

We must remember that our primary responsibility is to the end consumer. Food packaging, while looking attractive and incenting the consumer to buy, must be safe from the time it leaves the manufacturing floor until its final destination. Otherwise, what comes off the press won’t be a better or prettier package, but a detailed story about another food product gone bad.

Color Resolutions International

Mr. Schlinkert has spent more than 30 years in the printing ink industry and serves as director of technology for Color Resolutions Int’l., heading up its product development and service laboratories.