Gel packs vs. instant ice packs: which one lasts longer?

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Gel packs vs. instant ice packs: which one lasts longer?

Instant ice packs and gel packs are two types of ice packs that are great things to have available for emergencies situations. They are especially useful if you frequently use cold therapy treatments to help heal injuries and reduce swelling. Whether ice packs are needed frequently or infrequently, it’s nice knowing that the ice packs you have are durable and long-lasting. 

In this article, we will examine whether an instant ice pack or a gel pack is the best option for both emergency situations and for frequent uses. Both types of ice packs have their advantages, but we will discover which one has the edge over the other in terms of staying cool the longest and being the most durable.

First, let’s compare instant ice packs and gel packs

In general, ice packs can refer to any type of portable plastic bags that are filled with either water, refrigerant gel, liquid or dry ice (carbon dioxide). 

Aside from your traditional ice bags (i.e. bags filled with ice cubes), there are two other categories of ice packs: instant ice packs, which turn instantly cold when activated, and gel packs, which have to be frozen in advance before use. Instant ice packs contain two non-toxic chemicals in separate pouches. Squeezing the ice pack causes the pouches to burst, and the chemicals mix together to create an endothermic reaction that instantly lowers the temperature of the pack. An instant ice pack stays cool for about 20 minutes, although this can vary depending on the ambient temperature of the surrounding environment. One advantage an instant ice pack has over other types of ice packs is that they do not need to be stored in a freezer or even in a cool environment. They can be stored in a first aid kit or elsewhere warm and not lose any of its cooling abilities. 

A gel pack is often made of non-toxic phase-changing materials, such as hydroxyethyl cellulose (Cellosize), sodium polyacrylate or vinyl-coated silica gel, that remain in a slow-flowing gel state.

Gel packs are kept in the freezer and can be used for different purposes. They have the property of absorbing ample amounts of heat before it starts to warm again thanks to its main ingredient: water. Since water has a high latent heat capacity, gel packs are an ideal heat reservoir for keeping food, drinks, and injured body parts cool. The main composition varies from brand to brand, but ingredients like hydroxyethyl cellulose or silica gel, coated with vinyl, are usually supplemented with the water inside the gel packs to keep it from freezing into a solid block of ice. Gel packs stay cold for 20-40 minutes, also depending on its environment. 

A study at Michigan State University revealed that the melting points and latent heats of most of the gel packs tested were very similar to water. The shape and size of the gel pack also plays a significant role. One with a large surface area and a small volume of cooling agent melt faster but keep the product cooler. A gel pack with a small surface area and a large volume, the gel packs lasts longer but it is not able to cool as many products at one time. 

Which ice pack lasts the longest? 

A factor in the melting rate of an object is the amount of exposed surface area available for heat to transfer through. For example, individual ice cubes in an ice bag each have small exterior surfaces for heat to pass over – meaning the ice bag as a whole will warm and melt quickly. 

Gel packs, however, freeze as a solid. So the gel pack does not have more of a pure absorption capacity as the ice bag made up of individual ice cubes. In fact, they have less absorption capacity overall since the gelling additives subtract from the amount of water inside the pack. Hence, gel packs will take longer to melt due to the lower overall surface area. Additionally, gel packs do not get wet like it would with melting ice because the refrigerant gel is sealed in a plastic pouch. Additionally, since gel packs also use heavy-duty, puncture-proof plastic material, it prevents leakage caused by extreme temperatures and trauma. With all of the things above, it is safe to say that gel packs are the type of ice packs that last the longest and are definitely worth using rather than ice bags or ice packs.

The most noteworthy thing about gel packs is their versatility. Unlike instant cold packs or ice cubes, gel packs can be used multiple times, whether for cold or hot therapy purposes. Gel packs can be heated in a microwave. So, if you’re suffering from recurring conditions like arthritis and need to alternate hot and cold therapy on a regular basis, a gel pack is perfect for you.

Last but not least, since gel packs have advantages in ease of use and storage. They are also reusable, so it is economical and environmentally friendly. These handy products also come in various shapes and sizes. A single gel pack can be applied to nearly every part of the body. You won’t need to purchase different gel packs for ankles, knees, shoulders, back and so on. This can save you a lot of money in the long run. Gel packs are also safe to use on pharmaceutical and food items as they will not contaminate the products.

Got a question or anything I can help with?  My name is Steve Stretton, I’m the owner and manager at and you can drop me a line here.  Good luck!


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