Food Grade Ink: What is That?

Food grade ink is a specialty ink that is used for the packaging of foods. It is important to know what is being used in the packaging of the foods you eat before buying and consuming it. Food grade ink was created to be safe for consumption. When you buy any food with ink or dye printing on it, look at the label to make sure the imprint is made with food grade ink.

Every country has its own guidelines for their food imprinting, so it’s important to also know where the food imprinting dye is made and the specifics of the regulations of the countries related to food dyes. In some US states, there are stringent guidelines to follow when it comes to food dyes.

Around 19 states heavily regulate food packaging. They have “toxins in packaging laws” designed to regulate the use of heavy metals in food packaging. For instance, the intentional use of cadmium, lead, hexavalent chromium, and mercury is prohibited. The law states that these metals cannot exceed 100ppm as a total of all combined heavy metals.

Consider how challenging it is to imprint on food products. If it’s not designed for use on food, it will smear and be illegible. If it has heavy metal content, it’s not only prohibited in 19 states, it’s extremely unhealthy for consumption. Therefore, the guidelines and technical requirements for making food grade ink are tricky to say the least.

Why do food manufacturers use imprinting on foods? They primarily use it for decorative purposes and security reasons.  Those numbers you see imprinted on fruits and vegetables are special codes. Often times, UV ink is used that isn’t visible to the naked eye, but only to UV scanners. Additionally, this kind of ink for food packaging can come in direct contact with the very food you consume. That’s why manufacturers are so careful about the ink they use.

While there are laws in certain states about what can be used in foods, food grade ink isn’t certified by the FDA. Other than following the regulations related to FDA safe practices guidelines, this industry is not overly regulated. GRAS, generally recognized as safe, is the only recognized practice for food grade ink.

Ideal Attributes of Food Grade Ink

What are the ideal attributes of food grade ink? Ink jet printing is the accepted form used for decorating and printing on edible items. There are certain adjustments that are made to accommodate the various types of surfaces on foods that are imprinted.

Each adjustment in the ink fluid has to have just the right smear resistance, viscosity, solubility, surface tension, and drying times respectively. The appropriate chemistry, or make-up of the fluid and the ink itself are the two continuous aspects of industrial inkjet food printers. These functions are what help create the perfect properties for food imprinting. Different types of food grade inks are used in different types of inkjet food printers.

Currently, there are only a few food grade inks that fit into the appropriate compatibility scheme of food imprinting. Several tests are conducted to ensure the water levels are perfect so the ink doesn’t smear. Also, having harmful substances in the ink that cause health problems is another issue that manufacturers face.

New Food Grade Ink Technology and Printing Methods

Newer technology and methods are constantly being tested and tried to improve the process of food grade ink and dye imprinting. The toughest standards for making chemical-free food dyes are found in Europe.

One of the many methods used is to print on edible rice paper and then stick that to the food surface. However, that method doesn’t work for all food surfaces. This process is also expensive in labor costs, which is not conducive to manufacturers’ budgets. The more they have to pay laborers, the more the consumers pay for their food.

The Contents of Food Grade Ink

Commonly, food grade formulas have at least one food grade dye and one food grade glycol like propanediol, which is used to print directly on the food’s surface. High-quality food grade ink contains non-toxic substances. The water percentages range from 20 wt percent to 35 wt percent, but is closer to 1 wt percent. Glycerin is another ingredient used for making food grade ink. Its role is to be a co-solvent for colored inks. Synthetic or natural dyes are ingredients used in food grade ink. These dyes are water soluble or soluble in co-solvents.

Synthetic dyes that are used in the making of food grade inks include

  • FD&C Red #3
  • FD&C Red #40
  • FD&C Yellow #5
  • FD&C Yellow #6
  • FD&C Blue #1
  • FD&C Green #3

These dyes are created using various vegetable juices like beet extract, chlorophyll extract, spinach extract, grape skin extract, turmeric oleoresins, gardenia extracts, and cochineal extracts. The minimum for purity expectations for making food grade ink is 85 wt percent. No more than 15 wt percent of moisture, impurities and contaminants can be found in the ink.

Finally, food grade inks have additives that are used as preservatives, antioxidants, tension modifiers, buffering agents, thickening agents, and antimicrobial agents. A small percentage of isopropanol or ethanol alcohol is added to food grade inks.

How Food Grade Inks Are Used

  • Direct printing on foods – This is a fast-drying, odor-free ink for use directly on fruits and vegetables.
  • Cardboard cartons and cases – Corrugated cardboard, cases, and cartons use food grade ink.
  • Plastic or film packaging – Coffee, nuts, and other foods packaged in plastic bags, trays, pouches, or shrink wrap are imprinted with food grade ink.
  • Glass bottles – Glass bottles that contain edible items are imprinted with food grade ink.
  • Food and beverage cans – Soups, sauces, sodas, juices, and vegetables that are packaged in cans have food grade ink stamped on the cans.

These are the facts about food grade ink every consumer needs to know before they buy and consume food. Do your research to avoid toxic substances in your foods, including the use of food grade inks that aren’t well regulated.

This article was written by Erryn Deane from Needham Ink.