Thermal Insulated Bags in Last Mile Delivery

Today’s customers expect fast, reliable doorstep delivery without having to worry about getting home on time. To meet this demand, warehouses, distribution centers, and fleets have ramped up operations, fulfilling orders at an unprecedented pace to enhance the customer experience. At the very end of this network is the “last mile”—the critical final journey that delivers products directly to the customer’s doorstep.

This last stage of delivery is harder for businesses like food delivery services, grocery chains, pharmacies, and any enterprise handling temperature-sensitive items. Thermal insulated bags help protect these products, maintaining cool or refrigerated temperatures, year-round, until the package is finally collected by your customer.

Once a package leaves a cold chain facility, the clock starts ticking. Delivery services and 3rd party fulfillment companies have software to speed up transit times, but once the product is at the doorstep, when the recipient unpacks the goods is unpredictable. A package can stay by the door for twelve minutes or twelve hours. Regardless of how long the package stays outside, the integrity of the product will reflect on the company’s ability to deliver.

Thermal insulated bags provide a buffer in this final phase of cold chain logistics, bridging the gap between the distribution hubs and the consumer’s hands. 

What Is a Thermal Insulation Bag?

A thermal insulation bag is a pouch or stand-up bag designed to keep contents inside at a stable temperature during transport by providing a barrier against ambient temperatures. These bags are essential for the food and pharmaceutical industry and can be used along with gel packs

IPC’s Thermal Insulation Bag Options: CooLiner and CelluLiner

IPC offers two main types of high-performance thermal insulation bags:

1. CooLiner Thermal Insulation Bag:Constructed with a durable metalized foil bubble material, the CooLiner Delivery Bag is a variation on flagship CooLiner material. The reflective foil exterior reflects the heat, while the internal bubble layer provides a buffer to protect from heat penetration. This bag is perfect for chilled/refrigerated food deliveries, thanks to its sturdy handle and peel-and-seal adhesive closure. The bag provides all weather protection due to it’s water resistant outer layer.

2. CelluLiner Thermal Insulation Bag:

   For businesses with an eye on sustainability, the CelluLiner thermal insulation bag is a paper-based thermal insulation bag that’s curbside recyclable. With a patented multi-layered paper structure that traps insulating air pockets, CelluLiner offers excellent temperature control and can be conveniently recycled in curbside bins, making it ideal for companies looking to reduce waste.

3. CooLiner Insulated Box Liner:
   
   For businesses like meal kit delivery services that require more spacious and robust thermal protection than what standard-sized insulated bags provide, the CooLiner Insulated Box Liner offers an ideal solution. With its durable, reflective foil and insulating bubble layers, the CooLiner insulated box liner is custom made to your box size and will maintain consistent temperatures, ensuring freshness and quality for up to 24 hours.

Choosing the Right Thermal Insulation Bag for Last-Mile Delivery

Selecting the right thermal insulation bag for last-mile delivery depends on product needs, environmental considerations, and delivery requirements.

Case Study: Testing Thermal Insulated Bag Performance in High Temperatures

Objective:
Evaluate the performance of a 12″ x 7″ x 17″ curbside recyclable thermal insulated bag in keeping various perishables under 60°F during a 3-hour test in a high-temperature environment.

Test Setup:

• Contents: Chicken breast (16 oz), sausage links (13.3 oz), whole milk (64 oz), yogurt cup (6 oz), and cheese (16 oz)
• Pre-shipment Temperature: 36°F
• Bag Weight:7 oz
• Refrigerant: None used
• Temperature Profile:
  • Phase 1: 75°F for 0.5 hours
  • Phase 2: 100°F for 2.5 hours

Test Duration: 3 hours

Results

After 3 hours, the thermal insulated bag successfully maintained all perishable items under the target temperature of 60°F, despite exposure to peak temperatures of 100°F for over 2 hours. This outcome underscores the bag’s efficiency in preserving cold chain conditions without the use of additional refrigerants, making it ideal for short-term last-mile delivery solutions in extreme heat scenarios.

Conclusion:

The thermal insulated bag proved effective at maintaining food safety and quality during transit in high-temperature conditions, demonstrating its potential for use in urban grocery and last-mile delivery.

FAQ About Thermal Insulation Bags

1. Do insulated thermal bags work?
   Yes, insulated thermal bags are designed to keep items at a stable temperature for extended periods. They work by using materials that slow down heat transfer, effectively keeping cold items cold and hot items hot.
2. What is the difference between a thermal bag and an insulated bag?
   Thermal bags and insulated bags are similar in construction, both designed to maintain the temperature of their contents. However, thermal bags typically include additional heat-reflecting materials, like CooLiner’s metalized reflective layer, making them better suited for temperature-sensitive deliveries.
3. How long does a thermal bag keep things cold?
   A thermal bag can keep things cold for up to 24 hours. Temperature duration depends on the type of the insulator, ambient temperatures and amount of refrigerant being used in the bag during transport.
4. Will a thermal bag keep food frozen?
   Yes, a thermal bag can help keep food frozen for a limited time, especially when the food is shipped below freezing and has a refrigerant like dry ice. However, the duration depends on factors like the type of the insulator, ambient temperatures and how often the bag is opened. For extended freezing, a thermal bag will not be enough without higher quality insulators like an insulated box liner.
5. How long does a bottle last in a thermal bag?
   A bottle can stay cool in a thermal bag for approximately 2 to 6 hours, depending on factors like the type of the insulator, ambient temperatures and the initial temperature of the bottle. Using ice packs or pre-chilling the bottle can extend the cooling duration.
6. Can you put ice in a thermal bag?
   Yes, you can put ice in a thermal bag to help keep the contents cold. However, it’s recommended to use ice packs instead of loose ice to avoid potential leaks and prevent water damage to the contents inside in the event of a leak. Ice packs provide a cleaner and more controlled way to maintain a cold temperature inside the bag.