Insulated Bags

What Is an Insulated Bag?

An insulated bag is a packaging solution made by combining a metallized (aluminium foil/PET) outer surface with an inner insulating layer of bubble wrap or foam, which slows heat transfer between the product and the outside environment. The insulation does not maintain a fixed temperature; it helps the product hold its existing temperature for longer during transport.

PAKKORA's Range of Thermal Products

PAKKORA's insulated bag range is available in eight different formats:

• Insulated carry bag: An insulated bag with a lid and carry strap, used for courier and last-mile deliveries.
• Metallized thermal bag: A reinforced carry bag with a fully metallized outer surface, for larger-volume products.
• Thermal pouch: A zippered or sealable metallized pouch for small-volume products or samples.
• Thermal cargo envelope: A padded envelope offering protection against cold, heat and moisture, used for cargo and courier shipments.
• Thermal box liner: A metallized liner placed inside a standard cardboard box to give the box thermal protection.
• Thermal pallet cover: A large-scale metallized cover that wraps an entire pallet load and is secured with strapping.
• Thermal pallet blanket: A foldable, quilted pallet blanket with buckle straps, built for repeated reuse.
• Thermal liner roll: Raw metallized insulation material supplied in roll form and cut to size as needed.

Cold Chain and Temperature-Sensitive Products

Insulated bags are not limited to cold chain food products; pharmaceutical insulated bags and sample transport bags are also used to keep temperature-sensitive medicines, vaccines or laboratory samples within a safe temperature range throughout transport. Shipments like these usually need to be combined with an additional cooling source, such as a gel ice pack or dry ice — the bag itself is not a cooling source, but an insulating layer that slows heat transfer.

Choosing the Right Format

The right format depends on the scale of the shipment: a thermal pouch or cargo envelope is enough for a single sample or small package, while a thermal box liner is preferred at e-commerce carton scale. For courier deliveries, a reusable insulated carry bag or metallized thermal bag is the better choice, while full-pallet or air cargo scale calls for a thermal pallet cover or thermal pallet blanket — an air cargo thermal pallet cover in particular is preferred on long routes where temperature swings inside the cargo hold are significant.

Disposable and Reusable Options

Box liners cut from thermal liner roll are generally disposable and stay with the recipient along with the shipment. Buckle-strap pallet blankets and stitched carry bags, by contrast, are designed for repeated use as long as they remain undamaged — for businesses with regular internal shipping volumes, a reusable thermal cover like this can be more economical over time than a disposable thermal cover.

How It Works

The metallized outer surface reflects a significant share of sunlight and radiant heat, while the bubble or foam layer underneath slows heat transfer by conduction. Working together, these two layers reduce how quickly the product's internal temperature reacts to sudden changes in the outside environment; insulation time is limited, however, and may not be sufficient on its own for very long routes.

Insulation effectiveness depends largely on the number of layers and how tightly the cover wraps the product; wherever gaps are left, outside heat penetrates faster. This is why, especially with large-scale products such as pallet covers and blankets, covering the entire surface of the load without gaps and securing it tightly with strapping or buckle straps has a direct effect on insulation performance.

Use Alongside Other Products

Because thermal insulation cannot remove moisture from inside the enclosure, using a container desiccant inside a closed thermal cover or liner reduces the risk of condensation on temperature-sensitive loads. For temperature-sensitive liquids on long-distance flexitank shipments, a thermal pallet cover can be considered as a complementary layer.

Common Mistakes

• Expecting long-route performance without an additional cooling source: An insulated bag does not provide cooling on its own; without a gel ice pack, internal temperature will gradually approach the outside temperature on long routes.
• Choosing the wrong format: Trying to use a pouch designed for a single product at pallet scale provides inadequate protection.