Keep items Cool with Ice Gel Packs!

Keep items Cool with Ice Gel Packs!
Published On:November 19, 2021 Revised On:September 21, 2023

The journey of goods from production to the consumer’s hands often spans continents, crossing varied climatic zones. This journey can be fraught with challenges for products with specific temperature requirements, from pharmaceuticals like vaccines and biologics that lose their efficacy or can even become harmful if exposed to temperature fluctuations to perishable foods that can spoil and become a health hazard.

Cold chain packaging ensures the temperature-sensitive contents remain within a specified temperature range throughout its transit and storage life. By leveraging insulating materials, refrigerants, and even technologically advanced temperature monitoring systems, cold chain packaging aims to maintain the product’s integrity, freshness, and, in some cases, sterility.

Understanding Ice Gel Packs

Ice gel packs, often referred to as gel packs, are typically composed of a water-based gel solution contained within a plastic pouch. The exact composition of the gel can vary. Still, it often includes water mixed with a polymer or cellulose to increase viscosity and sometimes even added salts or refrigerants to modify the freezing and melting points. This gel mixture is sealed within the pouch, refrigerated or frozen until use.

The structure of these packs is designed for both flexibility and durability. The pliable nature of the gel allows it to mould around products, ensuring more even cooling, while the robust plastic exterior ensures that the gel remains contained, even under the pressures and strains of transit.

Benefits Over Traditional Ice

One of the primary issues with using ice is the water it produces as it melts. This can potentially damage products or packaging. Gel packs, in contrast, stay contained, minimizing the risk of leakage and water damage. Gel packs also have a more stable and prolonged cooling capability. Unlike ice, which can quickly melt and lose its cooling capacity, the gel retains cold for longer, ensuring sustained temperature control.

The flexibility of gel packs allows them to be used in various shapes and sizes, making them more adaptable to different packaging needs. They can be folded, bent, or placed in tight spots, ensuring optimal use of space within a container. Many ice gel packs are designed to be reused multiple times. This reduces costs in the long run and is more environmentally friendly as it reduces waste. Ice can introduce contaminants, especially when sourced from unknown or non-purified origins. Gel packs are typically made in controlled environments, ensuring they’re free.

Phase Change and How It Helps

Phase change refers to the transition of a substance from one state of matter to another, such as from a solid to a liquid. In the context of ice gel packs, the phase change primarily concerns the transition from solid (frozen gel) to liquid (thawed gel). When a substance undergoes a phase change, it either absorbs or releases energy, depending on the direction of the transition.

Ice gel packs’ melting process (solid to liquid) requires energy. This energy is extracted from the surrounding environment, leading to a drop in temperature. This endothermic process, where heat is absorbed from the surroundings, results in a cooling effect. The efficiency of the gel’s phase change material ensures that this cooling effect lasts longer than with standard ice.

Temperature Maintenance Duration

One of the major advantages of ice gel packs over traditional ice is their ability to maintain a consistent temperature over an extended period. The specific composition of the gel allows for a slower and more controlled phase change, resulting in prolonged cooling. This delayed phase change means the pack can absorb more heat from its environment before fully transitioning to a liquid state. This makes it particularly effective for longer transit times or storage durations.

Factors Affecting the Performance

Several factors can influence how well an ice gel pack performs its cooling function:

  • Initial Temperature: The starting temperature of the gel pack can impact its cooling duration. A colder pack will generally last longer.
  • External Ambient Temperature: Higher external temperatures can expedite the melting process, shortening the effective cooling period.
  • Insulation: The type and quality of insulation used alongside the gel pack can either enhance or hinder its performance. Good insulation can extend the gel pack’s effectiveness by reducing the rate of external heat infiltration.
  • Size and Volume of the Gel Pack: Larger or thicker gel packs typically contain more cooling gel, which can extend the duration of the cooling effect.
  • Airflow: A constant flow of warm air around the gel pack can hasten the melting process. Sealing products within a confined space with minimal air circulation can prolong the gel pack’s cooling period.
  • Composition of the Gel: Different gels have varying compositions, which can alter their freezing points, melting rates, and overall cooling capacities.

Applications of Ice Gel Packs

The applications of ice gel packs in cold chain packaging span many sectors, ensuring that products, whether life-saving medications or gourmet meals, reach their destination with their integrity uncompromised. This protects economic investments and, in many cases, is vital for health, safety, and the enjoyment of the end consumer.

Pharmaceuticals and Biologics:

  • Vaccines and Medications: Many vaccines and certain medications have stringent temperature requirements to ensure efficacy and safety. Ice gel packs can maintain these required temperatures for extended durations, making global distribution feasible.
  • Biological Samples: Transporting blood, tissue, or DNA samples often demands specific temperature conditions. Ice gel packs ensure that these samples remain viable and uncontaminated during transit.
  • Clinical Trials: Temperature consistency is vital when shipping investigational medicinal products for clinical trials. Any temperature deviation could compromise the trial’s integrity.

Food and Beverages:

  • Seafood and Meat: Freshness is paramount for perishable items like seafood and meat. Ice gel packs can keep these products at optimal temperatures, extending shelf life and preventing spoilage.
  • Dairy Products: Items like milk, cheese, and yoghurt require cold environments to prevent bacterial growth and spoilage.
  • Frozen Foods: From ice creams to frozen dinners, ice gel packs help maintain the required freezing temperatures, ensuring taste, texture, and nutritional value remain intact.
  • Wines and Brews: Certain wines and craft brews can be sensitive to temperature changes. Ice gel packs can protect these beverages, ensuring they reach consumers in peak condition.

Speciality Chemicals:

  • Lab Reagents: Many chemicals used in research and development are sensitive to temperature fluctuations. Ice gel packs can ensure these reagents maintain their desired properties during transport.
  • Industrial Compounds: Certain manufacturing processes require temperature-sensitive speciality chemicals. Maintaining the right temperature ensures product consistency and safety.
  • Photographic Chemicals: Temperature changes can adversely affect the quality of many photographic chemicals. Ice gel packs help in retaining their effectiveness.

Horticulture and Agriculture:

  • Plant Cuttings and Seedlings: The viability of certain plant cuttings and young plants can be impacted by temperature. Cold chain packaging with ice gel packs ensures they remain robust and healthy during transit.
  • Seeds for Planting: Temperature extremes can affect seed germination rates. Maintaining a consistent temperature ensures higher germination success.
  • Fresh Produce: Fruits, vegetables, and flowers can have their shelf life significantly extended when stored and transported at optimal temperatures, preserving freshness and reducing waste.

Selecting the Right Ice Gel Pack

Choosing the appropriate ice gel pack is crucial to ensure the optimal preservation and protection of temperature-sensitive items. Depending on the transport or storage method, the weight of the gel pack can be a crucial factor. Heavier packs might offer prolonged cooling but could also increase shipping costs.

The dimensions of the gel pack should fit the storage or shipping container efficiently. It’s essential to consider whether the pack can be folded or manipulated to fit different spaces. Different gel packs offer varying durations of cold retention. Matching the gel pack’s cooling duration with the required time to maintain product integrity is essential.

Some products may react adversely when in close contact with certain gel pack materials. Ensure there’s no risk of contamination or damage. While gel packs are designed to reduce leakage, there may be some condensation. Consider using a secondary barrier or moisture-absorbing pad if the product is moisture-sensitive. Ensure the gel pack can maintain the necessary temperature range. Some products require just a cool environment, while others need freezing temperatures.

Pre-conditioning and Preparation

Most gel packs require a thorough freezing before use. Ensure they’re frozen solid and at the right starting temperature. Consider using temperature indicators or data loggers alongside the gel pack, especially for highly sensitive products.

This can help monitor the temperature and ensure it remains within the desired range. While the goal is to minimize warm air exposure, some air circulation can help distribute the cold evenly. Ensure the packaging allows for this without compromising the cold retention.

Best Practices for Storage and Reuse

Proper handling and storage of ice gel packs are essential to maximize their lifespan and effectiveness. Adhering to good practices can ensure that ice gel packs remain effective and durable, providing optimal temperature control for all cold chain packaging needs

Storing Ice Gel Packs Before Use

Before freezing, store gel packs in a cool, dry place, away from direct sunlight, which can degrade the pack’s materials over time. Lay gel packs flat in the freezer to ensure even freezing. This also prevents the gel from accumulating to one side, hindering optimal performance. If storing multiple packs, stack them with a piece of parchment or wax paper in between to prevent them from sticking together.

Thawing and Refreezing Guidelines

Allow gel packs to thaw naturally at room temperature. Avoid microwaves or hot water, as excessive heat can damage the pack’s material and decrease efficacy. Before returning the gel pack to the freezer, ensure it’s fully thawed. This helps preserve the pack’s composition and ensures a consistent freeze during the next use. If a gel pack has been in a continuous freeze-thaw cycle for an extended period, consider giving it a “rest” by letting it stay at room temperature for a day before refreezing. This can prolong the lifespan of the pack.

Shelf Life and Signs of Wear and Tear

Before each use, inspect the gel pack for any signs of damage, such as punctures, tears, or severe discolouration. If certain areas of the gel pack remain hard even after thorough thawing, it might be a sign that the pack’s composition has been compromised. Limit UV exposure, as prolonged exposure to direct sunlight can degrade the plastic and gel.

If the plastic starts to yellow or become brittle, it might be time to replace the pack. Monitor for leakage and discard the pack immediately if any gel leakage is noticed. Gel leakage indicates a breach in the pack’s seal, making it unsuitable for further use. Even with optimal care, all gel packs have a finite lifespan. Replacing them every few years or sooner is advisable if they show signs of wear and tear.


The benefits of these packs stretch beyond mere temperature maintenance. They signify a commitment to quality, safety, and the preservation of product value from origin to destination. As industries grow and diversify, the demand for efficient cold chain solutions will only escalate.

Stream Peak manufactures ice gel packs in Singapore using Japanese technology and materials. We are ISO 9001 and ISO 14001 certified. Contact us to schedule a consultation with our packaging engineers to find out more about our ice gel packs and cold chain packaging solution.