Product Labels for Hot Fill or Warm Fill Applications

As consumers become more conscious of the effects preservatives and chemicals have on their health, sterilization is becoming the preferred way for safely packaging food and drinks. There are only two sterilization alternatives, however – cold aseptic filling or hot filling. The aseptic method is a fairly complicated decontamination process that uses chemicals like hydrogen peroxide to clean containers before they are filled; stringent safeguards have to be used to prevent contamination.
Most manufacturers tend to use hot fill processes to inhibit bacteria in food and beverages with high acidity such as spaghetti sauce, salsa, fruit and vegetable juices, teas, non-carbonated soft drinks and flavored waters that contain sugar. Hot filling is also used for household cleaners, detergents and automobile additives.
Known to extend the shelf life of food products up to 6 or 12 months, hot filling sterilizes the inner surface of a container and its lid. It is a rather inexpensive and conventional filling method that is often used simply because it is easier to pour hot liquids than cold solutions. As hot air is expelled from a container and a seal is applied, a vacuum is created inside the container. Usually the container has to be cooled down with a shower or steam once it is filled. Certain foods or drinks such as fruit juices even need to be quick chilled to retain taste and vitamin content.
Perhaps you are familiar with the canning process where glass jars are sterilized in hot water, filled with fruits or vegetables and then vacuum-sealed for long-term storage to get you through the long winter months?  In modern mass production processes, glass is also used but so are plastic containers which are less prone to breakage, are lighter weight and less expensive.
Do you have a container that needs to be filled with either hot liquids or food? Do you need to label that container prior to filling it? Will the label need to handle temperature fluctuations?
Salsa JarWhile glass is very stable, plastic containers will expand and contract with temperature changes and the last thing you want is a label that will wrinkle, bubble or flag as it moves with a container’s expansion and contraction. It is important to use the right type of label adhesive that will bond correctly and adjust to any surface changes.
The face stock is also important. For some producers, paper labels are appealing because they are economical. EIM has a couple great choices with an excellent all-temperature adhesive – 602 Matte or 617 Semi-Gloss Paper.
If you are labeling contoured or textured containers, you may find that plastic labels work better since they are made of more conformable polypropylene or polyethylene. Plastic labels have a certain amount of “slip” to adjust to a container’s changing size as it expands and contracts during the filling process. They also handle a wider range of temperatures and antibacterial cleaning systems. EIM offers both 666 white plastic and 5685 clear plastic films suitable for most hot or warm fill processes.
For us to suggest the right label, our Label Experts will need to fully understand your container filling application:
• When are your labels to be applied – before or immediately after filling?
• At what temperature are the containers when the labels are to be applied?
• What is your container made of – glass, plastic, other?
• What size label(s) do you need?
• What is your exact filling and sterilization process?
We will provide you samples so you can thoroughly test them since it important to evaluate any label material throughout your entire packaging process. If our standard products don’t quite fit your requirements, we have other options for your consideration. Simply contact our Label Experts.
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