- September 30, 2004, Dr. Richard M. Podhajny, Ph.D. Contributing Editor
Packaging engineers are designing new products to meet the growing demand for food packaging items that can be prepared quickly and conveniently by the consumer.
As these new packaging concepts are brought forward, greater demands are put on the inks and coatings to meet consumers' food processing conditions. These applications include paper plates, fast food items such as paper or metallized paper wraps, microwave or oven trays, as well as food contact items for cheese, dairy, meat, salads, etc.
Microwave and oven-heated products can reach temperatures that degrade the packaging product and the inks and coatings as well. Heat sterilization, boiling water, hot fill, and pasteurization require suitable packaging materials that can resist these processing conditions. These requirements extend to packaging inks and coatings.
The FDA publishes a list of raw materials that can have food contact in the Code of Federal Regulation, CFR Section 21, Parts 170 — 199. Printing inks and coatings that contact food are considered food additives. There are two kinds of food additives: Direct Food Additives, substances intended to be in the food product, such as a food flavoring agent or preservative; and Indirect Food Additives, substances used in processing, packaging, holding, or transporting of food and have no functional effect in the food but reasonably may be expected to become a component of the food (also see p24).
Inks and coatings fit within this portion of the food additive definition and can contact the food in the following manner:
Direct Contact: directly contacting the food;
Indirect Contact: substances that might contact the food, such as outside food bag;
Incidental Contact: substances rarely contact food, where food contact is not expected.
This area often is confusing, since printing inks can be indirect additives and have direct, indirect, or incidental contact with the food. Regulations that are applicable to inks and coatings come under 21 CFR, Parts 175 and 176. Part 175 covers Indirect Food additives, such as adhesives and components of coatings.
21 CFR 175.105: Adhesives used as components of articles intended for use in packaging, transporting, or holding food.
21 CFR 175.300: Resinous and polymeric coatings intended as food contact surface in producing, manufacturing, packing, processing, packaging, transporting, or holding food. The coatings must be continuous.
21 CFR 175.320: Resinous and polymeric coatings for polyolefin films (OPP/PE). These coatings must be continuous.
Part 176 covers Indirect Food Additives used in paper and paperboard components. This part has many regulations, but only two are of interest in regard to inks and coatings:
21 CFR 176.170: Components of paper and paperboard in contact with aqueous and fatty foods.
Section (a)(5) is a list of substances that may be used without meeting quality assurance tests, as long as they follow the limitations mentioned in the section.
Section (b)(2) contains a list of substances that can be used but must meet the quality assurance tests mentioned in paragraph d of this section. These tests require extractions not to exceed 0.5 mg/in.2 of food contact surface. For various food types and temperatures, there are different solvents and extractive conditions to model the application.
21 CFR 176.180: Components of paper and paperboard in contact with dry foods. Lists components of paper and paperboard that can be in contact with food. Dry foods are type VIII and IX foods as listed in Table 1 of 176.170. Substances listed in this regulation are not required to meet quality assurance test limits.
New products that meet these more demanding processing conditions are being developed. Over the last few years, a new line of polymers was introduced by Johnson Polymer to meet the wider range of direct food contact applications. These new products are called Joncryl DFCs. These polymers have 21 CFR 176.170 clearance as components of paper and paperboard in contact with aqueous and fatty foods and 21 CFR 175.320 as resins and polymeric coatings for polyolefin films, such as PE and PP.
Other suppliers are expected to follow with similar offerings to meet the growing demand for safer consumer packaging products.
Dr. Richard M. Podhajny has been in the packaging and printing industry for more than 30 years. Contact him at 267/695-7717; email@example.com