Best time to label containers: Before or After Filling?

Labeling systems are an important aspect of the product packaging process, but at which stage should the label be applied? It all depends on the kind of product that is being sold. Certain factors must be considered when determining when a container should be labeled.

Factors determining when a product should be labeled

Choosing when to label mostly depends on surface compatibility and validity. Adding a label after the container is filled is better for most products.

Most companies follow the same. It is particularly important when creating labels that include a best-by date. If printing additional information on each container, like adding unique lot numbers and best-by dates for shelf life, it is necessary to ensure the information will stay the same if there's an interruption in production.

1. Clean and dry surface

While considering when to label, the main determinant is whether the product's container is most likely clean and has a dry surface. It ensures that the label will adhere properly and survive any further processing. It is important to note that a label could be damaged by temperature spillage or changes.

  1. The kind of product that is being packaged

Depending on the type of goods sold and the regulations governing labeling, there will be an optimal time to apply labels.

  1. Internal tracking labeling

Labels can be used for internal tracking. In case of packing several items in the container, adding a label with a barcode or other identifier at the start is helpful. It helps monitor the status of the container as it moves through the system.

Hot containers and Hot filling

Many food products use heat sterilization to control bacterial growth. It is usually accomplished by using "hot fillers." It is a process in which containers are filled with extremely hot liquid and sealed. Before pouring into the container, hot filler liquid is heated to a temperature of 194°F (90°C).

The container slips once it is sealed, letting the liquid touch the inside. The heat sterilizes the surface of the container inside. After sanitizing, water is sprayed through a cooling tunnel to cool the container. An air dryer removes water from the surface.

Back-up systems must be installed to ensure the product is kept at the proper temperature throughout the process. Initially, if the temperature is too low, the resulting product can cause contagions. It will make it a health and safety risk. It may affect quality if the product needs to cool down quickly enough. The production system should keep the container at maximum temperature for 15-30 seconds. For another two to three minutes, the production system should keep it above 180°F (82°C) for this process to be effective.

Hot filling and labeling

The hot filling has minimal impact on flavor and nutrient content and does not require additional preservatives. Hence, it is usually used for acidic products stored at ambient temperature. The heat creates a sterile environment inside the container. Foods with a pH under 4.6 are already in a hostile environment for contagions, so heat kills any leftover pathogens.

Hot filling methods are typically used on heat-resistant cans or in glass bottles. Because the containers are cooled and dried on the line, they are compatible with most label stock types. Choosing a paper is the most important consideration. It must remain stable in warm conditions. Labels can be applied after or before filling, but you must know that products can drip during filling.

On the other hand, the labels must be given some time before applying them if using steam-based retort processing. The heat and humidity are not conducive to precise labeling. So it is best to wait till the products are filled, dried, cleaned, and cooled to label the containers.

Cold containers and labeling

Cold products are also challenging, as they can interfere with the adhesive. The adhesives are more pliable at warmer temperatures than cold temperatures as they get saturated. In the case of bottling cold products prone to condensation, ensure the product line includes an air knife that blows away moisture to provide a dry, clean surface for label application.

Finally, need to choose an adhesive designed for extremely cold temperatures. It helps ensure the product label stays intact during consumption and handling.

Choosing the right type of labeling machine for the product labeling line can be challenging. Many adhesives have a limited application temperature range but can survive extreme temperatures once applied. In cases of emulsion, acrylic adhesives have a Service Temperature Range (STR), which is as low as -65°F (-54°C). Their Minimum Application Temperature (MAT) is usually not less than 0°F (-18°C).

It is important to consider the operating temperatures of labeling equipment. 360a Series machines have an operating temperature that range from 41° F to 104° F (5° C to 40° C). It needs to maintain the cold chain for temperature-sensitive products, which is a problem. Usually, the best solution is to add a room or heated cabinet to the cold storage area for the labeler. Only long enough for label application, the products are kept in this area to prevent them from getting too warm and degrading.

Labeling Hazardous Chemicals

The product type also determines when the container should be filled in the production line. Hazard Communication Standard (HCS) set by the Occupational Safety and Health Administration (OSHA) requires labeling hazardous chemicals before filling the container. These rules require that hazardous chemicals be properly labeled, marked, or tagged with their identities before filling or using them in the workplace.

The labels must be prominently displayed on the container, legible, and have health and physical hazard information. It ensures that employees know the potential hazards related to the materials and can take proper precautions to protect themselves. Before they are filled, label hazardous materials and ensure proper labeling in case of a spill or accidental release. Additionally, it helps stop mistakes in the filling process. Adding a printed label on the wrong product can be very dangerous.

Due to their risk, hazardous chemicals have stringent labeling requirements. These include indicating necessary details other than the product name, such as if the chemical is combustible, explosive, toxic or poses other safety and health risks. This information must be included in any secondary container. Include the same necessary information on this label as the original container, even if the product is a concentrate being diluted in a secondary container (like a plastic bottle). 

Importance of Labeling

Labels play a pivotal role in the product manufacturing and shipping industry. Here are some of the key reasons why they are of utmost importance:

  1. Identification and Tracking

Labels serve as unique identifiers for packages. They include the recipient's address, shipment origin, and tracking number. This information is vital for logistics companies to track and manage the movement of packages efficiently.

  1. Error Reduction

Labels help reduce the risk of errors in the delivery process by clearly stating the recipient's address and other relevant details. Accurate labeling ensures packages are delivered to the correct destination, minimizing costly mistakes and delays.

  1. Compliance with Regulations

In many industries, including hazardous materials transportation and international shipping, strict regulations govern the labeling of packages. Labels must include specific information and symbols to comply with these regulations, ensuring the safe transport of goods.

  1. Convenience for Recipients

For the recipients of packages, labels provide essential information about the contents and handling instructions. This information helps them handle the package appropriately, whether it contains fragile items or requires special care.


Applying a container label after it has been filled can be challenging. While it may be technically feasible in some cases, it raises concerns about accuracy, compliance, and efficiency. Implementing a labeling process post-filling requires advanced technology, meticulous planning, and stringent quality control measures to ensure the label's information aligns with the container's contents. Additionally, regulatory requirements must be taken into account to avoid legal implications. 

Beast Branding offers custom labels in all sizes, shapes, and quantities. You can also order stock blank labels from us. Don't forget to check our custom banner printing services to help create the perfect banner to exhibit your brand. 

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