When brand owners think about food safety in flexible packaging, they usually focus on the substrate, the film, the barrier layers, the sealant. But there is another critical component that is often overlooked: the ink.
Inks used on food packaging are not inert. They contain pigments, binders, solvents, and additives. If the wrong ink is used, or if the packaging structure does not provide adequate barrier protection, components of the ink can migrate through the substrate and into the food. This is known as migration, and it is a serious food safety concern.
What Is Migration and Why Does It Matter?
Migration occurs when substances from the ink transfer through the packaging material and into the food product. The rate and extent of migration depend on several factors: the type of ink, the thickness and barrier properties of the substrate, the food type (fatty, acidic, aqueous), the storage temperature, and the duration of contact.
Not all migrated substances are harmful. But some ink components—particularly certain photoinitiators, mineral oil hydrocarbons, and heavy metals—have raised health concerns. Regulatory bodies in the EU, the US, and other markets have established limits for these substances in food-contact materials.
Types of Food-Grade Inks
There are several ink technologies used in flexible packaging. Each has different performance characteristics and migration risks.
Solvent-based inks are widely used because they offer excellent print quality and fast drying. However, they contain volatile organic compounds (VOCs) and carry a higher migration risk if not properly dried or if the packaging structure lacks adequate barrier layers.
Water-based inks are increasingly popular due to their lower VOC content and reduced environmental impact. They are generally considered safer from a migration standpoint, but they can be more challenging to print with on certain substrates.
UV-curable inks dry instantly when exposed to ultraviolet light. They offer high durability and print quality. However, some UV inks contain photoinitiators that can migrate if curing is incomplete. Low-migration UV ink systems are available and are specifically designed for food packaging.
Electron beam (EB) inks are similar to UV inks but use electron beams for curing. They offer very high cure rates and low migration potential.
Low-Migration Inks
For food packaging, the industry has developed a category known as low-migration inks. These inks are formulated with raw materials that have a low tendency to migrate. They use high-molecular-weight photoinitiators, polymeric binders, and pigments that are tightly bound within the ink film.
Low-migration inks are not automatically safe for all applications. They must still be tested and validated for the specific food type and storage conditions. But they provide a much higher margin of safety than conventional inks.
How to Ensure Compliance
Compliance with food-contact regulations is not optional. It is a legal requirement in most markets. Here are the key steps.
First, understand the regulations in your target markets. The EU has specific requirements for food-contact materials, including Regulation (EC) No 1935/2004 and Regulation (EU) No 10/2011. The US FDA has its own set of requirements. Other markets have their own rules.
Second, verify that your packaging supplier uses food-grade inks. Ask for documentation, including ink safety data sheets and migration test reports.
Third, conduct migration testing. This should be done on the finished packaging, using food simulants that match your product type. Testing should be performed by an accredited laboratory.
Fourth, consider the entire packaging structure. Even the best ink will migrate if the substrate does not provide adequate barrier. A high-barrier film with a low-migration ink is the safest combination.
What Brand Owners Should Ask Their Supplier
When sourcing flexible packaging, ask these questions:
What type of ink do you use? Is it food-grade and low-migration?
Can you provide migration test reports?
Does the ink comply with EU and FDA requirements?
Have you tested the finished packaging with a food simulant that matches my product?
Do you have experience with similar products and applications?
The answers will tell you a lot about the supplier’s commitment to food safety.
Food packaging is not just about protecting the product from the outside world. It is also about protecting the consumer from the packaging itself. Choosing the right ink is a critical part of that responsibility.