After a few miles of hiking in the summer heat, nothing beats a refreshing ice-cold drink!

If you’re wondering how to keep drinks cold in a backpack, or if it’s even possible, stay reading for some top suggestions on how to keep your drinks cooler for longer while out on the road.

Keeping Hydrated

When trekking in the heat, it’s critical to stay hydrated. While your body will naturally grow thirsty as it strives to replace moisture lost through effort and cool down, sipping warm water on the path can be quite uncomfortable.

Keeping your drinks chilled in your backpack will definitely encourage you to drink more frequently and in consistent quantities, which means you’ll be less likely to dehydrate.

The Scientific Method

It helps to understand why hot drinks cool down, and cold drinks warm up if you want to keep your drinks chilled, or at least not too hot.

Both drinks, in essence, respond to the temperature of the surrounding environment. A cold drink absorbs energy from its surroundings, whereas a heated drink loses energy from its surroundings.

The second law of thermodynamics assures that an object and its surroundings reach thermal equilibrium in a closed system. Under normal circumstances, heat naturally flows from one object at a higher temperature to another at a lower temperature.

So, in general, if we want our cold drink to stay cold, we must limit the temperature difference between it and its surroundings. This will reduce the quantity of heat transferred to our drinks. Now that we’ve covered the science let’s put what we’ve learned into action!


Preparation is essential in many aspects of life. Begin by ensuring that your drinks are as cold as possible. If you’re leaving from home or elsewhere with access to a freezer, place your drinks in there to freeze. Keep in mind that water expands as it freezes, so don’t overfill!

If you’re staying in a hotel or hostel, your best chance is to get your drinks from a local store before you leave. Choose the coldest option at the back of the cooler if feasible.

Grab an ice pack or two and place them in the freezer if possible. Disposable thin plastic ice packs may be available in stores’ chiller cabinets.


Once you’ve gotten your hands on the coldest drinks you can find, the problem is to keep them that way for at least the next few hours. Because you can’t bring the fridge, you’ll have to find a technique to keep the beverages’ surroundings, i.e. your backpack, as cool as or cooler than the drinks to keep them from heating up.

What is insulation?

In a word, insulation is the process of filling spaces around an object with certain materials to limit the loss of cold or heat. Using cold drinks as an example, the interior of the insulation vessel cools as a result of your drink, allowing it to stay colder for longer.

Simultaneously, the insulation works to keep the warmer outside air away from your prized beverage. Insulation can also act in the opposite direction, keeping your hot cocoa or coffee hot in the winter.

Insulation is essential in this case to minimize temperature differences. Put your cold drinks in a plastic bag, preferably with an ice pack. Depending on your conditions, an insulated thermal bag would be best, but if you don’t have one, use any plastic bag to protect the rest of your stuff from water.

Wrap this around your sleeping bag, spare layer, or any other insulating items you’re carrying and stuff it into the bottom of your backpack. The better the insulation, the longer your drinks should stay chilled. Just don’t get anything wet if you have to wear it or sleep in it at night!

Personally, I prefer to freeze a plastic water bottle or two overnight and then cover them in plastic wrap to keep them as cool as possible for as long as possible. When I start out, I’ll make sure the water in my hydration bladder is cold (see below) so I have cold water for the first hour or two.

This allows me to easily reach cold water early in my trek while also keeping the interior of my backpack cooler. When the ice melts, I refill my bladder with water from the bottles.

Remember, they were frozen, so they will remain colder for a much longer period of time.

When the weather is hot, your drinks should stay cool in your backpack. They will eventually heat up as you consume them and with the passage of time, but they will be far more enjoyable to consume than warm, tepid water.

What insulation materials are used in coolers?

There is one insulator that rules them all when it comes to managing the temperatures of your favorite foods and beverages. This is for you if you’ve ever wondered what materials keep things cool. Polystyrene foam, also known as Styrofoam (a trademarked name), is the most common substance found in everyday coolers.

What exactly is polystyrene?

A polystyrene is a form of plastic that is used in a variety of applications ranging from insulation to food packaging. It can be turned into a foam-like substance known as expanded polystyrene.

This invention has a wide range of applications, including insulation, packaging, and noise reduction.

What is the manufacturing process for polystyrene foam?

EPS, or expanded polystyrene, is created in three steps. During the first phase, steam is delivered into polystyrene beads, which causes an internal hydrocarbon to boil. As a result, they can grow up to 50 times their initial size.

The beads are then treated in order to achieve the proper temperatures and internal pressure. Finally, the beads are warmed and placed in a mold. As a result, the space continues to expand, allowing for a full fill.

One thing to keep in mind is that once done, expanded polystyrene contains around 95% air.

What is the purpose of polystyrene insulation?

This incredible substance isn’t just utilized for insulation because it’s effective. Polystyrene is exceptionally lightweight, moisture resistant, recyclable, robust, easy to shape, and inexpensive to produce.

It is utilized as insulation in anything from foam cups, coolers, and refrigerators to floor wall and roof panel systems.

What about my bladder’s hydration?

If you want to utilize your hydration bladder in hot conditions, I would place some ice straight inside the bladder and insulate it firmly in the center of your pack.

Keep in mind that you won’t be able to freeze it because the tubes will split. Also, any water in the tube will warm up while you’re out, so take huge gulps or remember to drink more frequently to avoid it becoming too unpleasant.

Cheats tips for cold drinks

Take advantage of your surroundings. If your hike takes you near any creeks, prepare to dine somewhere close. When you arrive, place any warm drinks in the chilly waters and leave them for at least 30 minutes to cool.

They should be cool for later by the time you’re ready to go. Wrap them in a wet thing, then a plastic bag, and place them inside your backpack to insulate. If it’s extremely hot, you should take a dip or dampen your clothing and headwear.

Away from sunlight

If you leave your cool bags in the sun for too long, the bottle will warm up. Keep them hidden in the bottom of your backpack in the dark.

Even if your bags are insulated, warming the outside bag will have an effect on the interior container. This is a crucial technique for keeping beer cool on a trek if you love having an alcoholic beverage after a hike.

Sleeve for a can or a bottle

After completing all of the preceding processes, you are ready to enjoy your ice-cold beverage. You take out the bottle or can and grip it, ready to settle down and have a leisurely drink, only to discover that the ambient temperature and the temperature of your hand have warmed the can and the liquid.

The solution is to purchase one of those can or bottle sleeves and place the drink inside the sleeve when you remove it from your cool bag. This allows you to sip at your own pace without having to worry about the beverage warming up from your hand.

Use a Lifestraw

You could sip the cool water directly from the creek if you have a Lifestraw or something similar. If you know there will be water in the creek at that time of year, you may be able to reduce your pack weight by carrying less water. Remember to always verify ahead of time if the water is safe to drink, even if it has been filtered.

If your hike route takes you through any small towns or villages, check ahead to see if there are any local convenience stores that won’t need too much of a detour. This can also assist in reducing pack weight because you won’t need to bring as much water at the outset. You will expend less effort and perspire less if you carry less weight.

More tips

  • Make the ice colder – Mix salt into the ice to get it to react and stay colder for longer.
  • Roll up your soft individual bags — Keeping the bag compact reduces the amount of warm air that enters the cool bag.
  • Bring many cold drinks with you – Having more than one drink will help them last longer by cooling everything else in the bag.
  • Place little ice packs at the bottom of the bag — these square packs keep cold for hours and take up little space.
  • Freeze empty plastic water bottles — For DIY ice packs, place a tiny amount of water in a plastic water bottle and freeze overnight. Alternatively, use used shampoo bottles to make fantastic ice packs that stay even longer.

Product recommendation

SENDESTAR 64 oz Beer Growler Double Wall Vacuum Insulated Leak Proof Stainless Steel Water Bottle —Wide Mouth with Flat Cap & Spout Lid Includes Water Bottle Pouch (Black)
  • The water bottle is double-walled and made from high quality food grade 18/8...
  • Wide mouth makes it easy to clean, BPA-free lid which means they are very safe.2...
  • This Growler Won't Leak. lid with handle for easy carrying. While sitting...

My SENDESTAR stainless steel sports water bottle, depicted below, has been a summer staple for me. If you’re looking for a quick method to grab a cold drink and get out the door, this is hard to top.

I use it for the first few hours of my day treks, and it’s great for keeping a cool drink on hand without having to open and warm up the rest of my drinks.

It has a lock feature and a flip top, so you don’t have to worry about the rest of your gear getting wet. It’s also great for keeping your drinks warm in the cold, so you can use it all year.

The HYDRO CELL Stainless Steel Insulated Water Bottle is also a very good option. If I had to pick one feature to distinguish this bottle from others on the market, it would be that it is the king of variety. HYDRO CELL comes in seven different colors and four different sizes: 40, 32, 24, and 18 oz.

Keep in mind that only the 18 and 24 oz models fit in conventional cup holders. Another intriguing aspect is the addition of a powder-coated anti-slip layer, which is a great touch. It also includes a second lid for more sporty circumstances.

Lifewit Large Lunch Bag 24-Can (15L) Insulated Lunch Box Soft Cooler Cooling Tote for Adult Men Women, Grey
  • Premium Lining & Zipper: The lining of lunch bag is made of PEVA foil that won't...
  • Long-Term Insulation: The lunch bag is made of insulated material which can keep...
  • Wide-Open-Design: Top of the lunch bag can be opened up to 11.8”x9.1” by...

If you require a little more storage than Coleman provides, this could be the solution. Lifewit’s 24-Can Insulated Soft Cooler is a wonderful alternative to the Coleman. With a higher capacity, as you might expect, this is slightly larger than the previous entry, but it still allows for shoulder carry.

The Lifewit’s dimensions aren’t out of the ordinary; at 11.8″x9.1″x9.1″, it will readily fit in the bottom of most backpacks. The Lifewit claims to be 100% leakproof due to its apparent hot press manufacture.

It also has a more fashionable aspect, virtually making it a fashion statement. Finally, the Lifewit cooler costs a little under $20, making it a complete steal.

Yeti’s Hopper BackFlip applies the brand’s hallmark “make it to last forever” mentality to the next outdoor must-have. Daisy chains on the front and sides for connecting accessories, a handle on the top and sides for easy carrying, and, of course, comfortable backpack straps with sternum and waist belts complete the straightforward design.

Twenty cans fit into the 24-liter main compartment (30 cans without ice), which has enough ice to last two days. The large waterproof zipper and DryHide shell keep ice cold and water in a while, keeping out the elements. The Backflip is also available in 18- and 30-liter capacities.


Start with ice-cold water and enough insulation to keep drinks cool in a backpack. If possible, use on-the-go resupply sites and invest in a dedicated insulated sports water bottle, which can also be used to keep your drinks warm in the winter.

Remember that chilling good old-fashioned plastic bottles overnight before your journey can help to keep your water colder for longer, although this will be of little benefit on an extremely hot day.

If you’re going to be out in the heat for an extended period of time, don’t forget to drink plenty of water. Even if you are unable to keep your water as chilly as you would like for one reason or another, remember that drinking warm water will keep you hydrated.

So, whether it’s refreshingly cool or uncomfortably warm, keep drinking and staying hydrated!

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