I was asked this question the other day, “How Long Will Ice Last In A Cooler?” It seemed a pretty simple question at first glance, but then I realized that there were many different variables to consider when I looked at it more carefully.
Firstly to answer the question…How long does ice last?
If you read the article content below you will learn that there are many methods and actions you can take to increase the shelf life of cooler ice.
When choosing just one of the below tactics and applying the methodology to a run of the mill regular ice cooler, we found that in this scenario ice will comfortably keep in a practical useful state for at least 18-24 hours or roughly one day.
If you invest in a higher-end cool box and take the same precautions, regular ice can surprisingly keep its shape for up to three or four days, as long as the cool box is not continually accessed.
We conducted a couple of experiments of different cooler boxes. In the first box (a Styrofoam box) that was opened just four times in two days, after 36 hours, the ice was still 30% solid.
The rest had turned to water. A top of the range cooler like the Pelican Elite will kept the ice for solid five days with the ice cooler being opened occasionally over the course of the experiment. However, a box like the Pelican is going to cost more than $100.
Make sure to read on to find out how you can churn out the longest lasting ice in your cooler to the very last cube.
The variables have a considerable effect on the length of time on how long does ice last and, consequently, how cool the cooler itself will remain. Lets start by taking a look at what types of coolers there are available.
Type of cooler
Plain styrofoam box
Rigid cooler box
These boxes are typically made from Polypropylene and perfect for dry ice and block ice as well. Top of the range models may be made from aluminum and stainless steel. They have a rigid design and most suited for hiking trips.
Soft material cooler bag
These can be made from a variety of materials. These materials can include:
Canvass, Cotton, Neoprene, Nylon, Polyester, and Vinyl. They are made in the form of a bag with a zip fastener to seal the container.
The size of ice
Another significant variable when it comes to considering how long ice will last In a cooler is the size of ice used. The cubed ice melts when warm air touches the sides of the ice.
If you use small ice cubes, then there is a greater surface available for this interaction than if you use large block ice.
Cold air flow around the ice is a critical factor when it comes to how long the ice will last. An aspect of this is how much airflow is allowed into the cooler by opening the lid.
Every time you open the top, you will enable a rush of warm air to touch the ice.
It can help if the contents of the cool box are layered, Separate layers with sheets of plastic (or cooler insulation) that stop the air from flowing over all the ice.
Put ice in each level. For example, if you plan out how many soft drinks you need for every stage during the day and put in these plastic layers between the cans so that the top layer is used first without air reaching the second and third layers.
Make sure to keep your ice cooler in the shade as doing so will also help keep a longer shelf and make ice last longer. Placing the box in direct sunlight is a no no, and despite insulation, it will warm up faster than not doing so.
If you think about it, if you put warm items into a cool box and add the ice, that ice has got first to bring the water items temperature down to cold, then keep it cool.
You will lose some of this ice during this process. If instead, you pre-chill the product in the fridge (or even freeze) these items such as food, water bottles you are putting in the ice chest, then the ice does not have to work so hard keeping things fresh and will last longer.
Making ice last longer
It’s time to use a little science. Now, most of us know that the freezing point of pure water is zero degrees Celsius.
If you are planning to make your ice, then why not make saltwater ice. This ice gets much colder than regular ice, and as long as you keep the airflow at a minimum, it will last much longer.
The less warm air inside the cooler, the colder it stays. Fill the cooler up to the top with ice, and make use of plastic or insulation layers mentioned in the ‘Airflow’ heading above.
Think about putting bags of ice around the sides of the box. Find as many ways of insulating your content as you can.
Pack your box as compact as you can, once again reducing the contact of warmer air when the box is opened. Fill every square inch of the container with the stuff you want to cool or ice.
Ice to product ratio
You have to understand that ice keeps the content fresh, un-ironically the more ice frozen the more it keeps itself cool. There always has to be enough ice if your cooler is going to function.
It will help if you plan an ice to content ratio of 2:1 (2 ice for one content in terms of volume).
Use more than one cooler on your camping trip
Since we have already established that restricting airflow is crucial, why not bring two coolers?
Leave one sealed until later in the day after the first box is both emptied and warmed up. By leaving the second box untouched, the ice will remain much longer in that box and keep temperatures down.
Even though I could not give you a catch-all length of time that ice will last, I have been able to provide you with approximate time, depending on how many of the suggestions you follow and the complexity of your cooler.
I hope the tips I have provided are useful, and can be implemented to help keep ice and your ice chest as frozen as possible.