Beer Can Cooling Experiments

Here's some tests on cooling and keeping beverages cool. In some of the tests a can of sparkling water acted as a stand in for a can of beer. The emphasis being on cheap and easy ways to cool a beverage. I hope these tests increase your beer can cooling knowledge and assist you in your quest for a cool beverage.

Thermometer

Full Aluminium beverage can

I graphed the temperature of a can of beverage as it was being cooled in a fridge. What was surprising was how long it took to get from 11c down to 5c - about 5 hours. With a total time to cool a beverage can being 8 hours. Much longer than I thought it would take. As can be seen in the graph, as the temperature gets closer to the fridges temperature the cooling speed slows down.

Placing a beer in the freezer to cool it down fast is a common approach but if it's forgotten about and freezes, it is likely to leave a mess.

Results: Placing the beer inside the freezer cooled it down to 5c in 40 minutes. Ten minutes later it started to freeze. It's useful to set a timer when freezer cooling as if it's in too long you will end up with a frozen can.

A wet paper kitchen towel was wrapped around a beverage can and then placed in a freezer. It took 30 mintute to reach 5c. This was 10 minutes faster than just placing just the can in the freezer.

A couple of other tests for 30 minutes in duration, had the can with wet paper towel reaching 6.4c vs no towel 10.3c and 3.8 vs 7.7c. About a 4c difference in both cases.

A 5 kg bag of crushed ice was poured over soda water cans and 2 litres of water poured in.

The can with the temperature probe in it got down to 5c in 24 minutes. This is considerably quicker than when just ice was used (42 minutes to get to 5c) in an hour it was down to 2.5c - about the same as with just ice. It remained below 5c for a total of 11 hours - 4 hours less than when ice alone had been used. It was 13c after 15.5 hours. This was about 4 and a half hours less than when ice alone had been used.

Six cans were placed in a cooler bag, 5 kg of crushed ice poured over top. Then two liters of water poured in along with 1kg of salt.

The can with the temperature probe in it cooled to 5c in less than 10 minutes. This was half the time of ice and water. After half an hour the can was less than 2c. The can remained below 5c for 14.5 hours - an hour less than with ice and water.

Using a 'beer can spinner' a can was spun on a block of ice for 5 minutes. It cooled to 2.6c.

Spinning on ice is now my 'go to' way of quickly cooling an aluminum beverage can. It's quick and convenient.

Heat up 2 liters of water on a stove and add salt until no more will dissolve. Let it cool and then fill a 2-liter plastic bottle and place into the freezer. You will find it doesn't freeze. When you want to cool a beer, pour the super cold salt water into a container and a place a beer can in it for 10 minutes. It will cool the beer down to below 5c. The salt water will then need to be 'recharged' by pouring it back into the bottle and cooling it again in the freezer. Personally, I prefer spinning a can on a block of ice to cool it.

To observe how a beverage loses its cool over time (warms up): 400mils of water was cooled to 5c. Then its temperature was graphed as it warmed.

Conclusion: when very cold a beverage loss its cool quickly (5c to 10c in less than 15 minutes) as it warms, it losses its cool at a slower rate (nonlinear graph).

Measuring the warming of another beverage can on a colder day had it increasing from 4c to 10c in 24 minutes, reaching 17c after 1-hour 15mins.

These tests demonstrate a couple of things:

• That cold beverage brought home after purchase probably aren't that cold anymore.
• The rate a beverage loses it cool, reduces the closer it gets to room temperature.
• The rate a beverage loses it cool is faster on a warm day than on a cold day.

Cooling a beverage is only part of the story - the other part is keeping it in the 'drinking zone' (2c -5c) while being consumed.

What's the point of cooling beer if while you are drinking it, it goes beyond the 'drinking zone'? Prevent this by placing the beer can in a stubby holder. By placing a beverage can cooled to 0.1c into a 6-millimeter-thick neoprene stubby holder, it remained below 5c for 36 minutes.

A second can was cooled and then tracked without using a stubby holder - it reached over 5c within 16 minutes. Stubby holders work! It's likely both will warm up quicker outside on a sunny day.

No real need to read about the tests which follow.

Even when a stubby holder is used, on a very hot day in direct sun and in the middle of the day a beverage will heat up quickly. In the middle of a 37c day (the hottest day in a couple of years) the temperature of a beverage can in a stubby holder was recorded. In less than 6 minutes it had increased to more than 5c and in 10 minutes it was about 8c. Without a stubby holder, a beverage can increased to more than 8c in 5 minutes and in 10 minutes it was over 13c. Drink in the shade on hot days.

Having accidentally made a tube of ice, I thought I would see if this would cool down a drink. I also remember ice being used to cool beer while visiting Loas. The ice was placed directly into a large glass, with 200 mills of tap water in it. After 4 minutes the water had cooled to 4c. (2 mins to 9c, 3 mins to 6c) but the volume of water had increased to 300mls. So placing the ice in the water had diluted it by 50% - not a desirable way to cool down beer!

What if a lemonade ice block was used to cool beer? A 10%, barrel age imperial ale was chosen for this test as I thought it might survive a dilution factor of 50% with lemonade and might even make for a good 'shandy'.

Result: the beer was cooled down to 7c in 4.5 minutes making for an enjoyable beverage.

Some beers were placed in an insulated box next to some dry ice (frozen CO2). They were removed 6 hours later and had cooled to -4.9c. This is too cold to enjoyably drink, especially on a 14c day. After about 15 minute the beers had warmed to 1.3c which is still on the cold side. Maybe, when the outside temperature is below15c and falling, beer doesn't need to be cooled further...

Having sourced some dry ice (frozen CO2) I tried cooling a beverage by placing a lump into a cup of soda. It boiled over at the start but cooled the drink quickly: from 14c to 1c in less than 2 minutes. I would not recommend this as a way to cool drinks because:

• You loss beverage from the beverage bubbling over.
• Dry ice needs to be carefully handled.
• You don't want to risk still having any solid dry ice remaining while drinking the beverage.

On the plus side, it doesn't dilute the beverage while it is being cooled.

A 5 litre water pack was frozen and placed in a 25 litre 'tote bag' which was meant to keep things cold for about 6 hours. The bag only got down to 10c for about 3 hours before going up to about 14c. After 8 hours most of the ice in the water bag had melted. The original idea was to freeze the 5-liter water bag so it would keep things cold and then the water could be drunk but the set up doesn't look like it will cool beer cold enough, maybe it would work better as a way to keep cold beer cold rather than as a means to cool it.

To see the impact of adding salt to ice and water and spinning a can in it, 20 grams of salt was added to 450ml of ice with a little water. The temperature of the ice/water mixture was measured to be 1c (photo 1a). A beverage was spun in it for 3 minutes and was cooled down to 7c. The ice/water temp had increased to 2c (photo 1b).

An additional 40 grams of salt was added, the ice/water went down to 0c. A second can was then spun for 3 minutes. The salt/water temperature increased to 3c, the beverage can was cooled down to 7c. (Photo 2).

A second 450ml tray of ice was added, along with 100gms of salt (making a total of 160gms). The ice/water was measured to be -3c. A beverage can was spun for 3 minutes. This cooled the can down to 5c.

Conclusion: adding salt will reduce the temperature of ice/water by about 4c if enough salt is added (about 16% in this test) - reducing the time the beverage can needs to be spun by a minute or so. It does however create a bit of a salty mess.

The 16% salt-water solution was poured into a couple of ice trays and frozen. The frozen cubes were put it a container and the temperature of the somewhat mushy ice measured to be -10c. When a beverage can was rotated in the mushy ice using a battery powered screwdriver the salty ice temperature rose to -7c.

Next, a 3-volt, 500 rpm mini spinner was tried but couldn't rotate the beverage can when placed next to the salt-water ice cubes. A 6-volt 300 rpm spinner was able to rotate the can. It was rotated for 3 minutes and cooled the beverage down -0.4c. This was a little below the ideal 'drinking zone' (being 2c to 5.5c) but would give the maximum time in the drinking zone as the beverage losses it cool.

Spinning a can in salty ice blocks is a superfast way to cool beer.

It was observed that water in an aluminum can expands when freezing causing the can to distort and split. A 'sugar drink' beverage can was placed in the freezer - it didn't split. The 15% sugar having an effect.

A frozen 250ml can was placed into 375mls of beverage (contained in a larger can). The surrounding beverage was cooled down to 5c in 10 minutes.

A test was done on cooling near boiling water. The boiling water was placed in a beverage can which had its lid removed. This was then placed in a larger can of tap water. A few things were observed:

* The water cooled down quickly in the first minute - from 94c to an estimated 60c.

* There were different temperature bands in the hot water can - after 2 minutes liquid near the top was 61c while at the bottom 31c (heat rises).

* The speed of cooling was proportional to the temperature differential. At the beginning the temperature decreased rapidly but once at about 40c the decline was a lot slower.

" The temperature of the water surrounding the can rose to about 32c.

* One way to cool hot coffee to ice coffee would be to firstly cool it to about 45c in a tap water bath and then continue cooling it in an ice water bath, thus conserving ice cubes.

The speed of cooling a beverage can is proportional to the temperature differential of its cooling medium.

Frozen Vermouth has an alcohol content of about 14% and freezes / melts at lower temperature than ice. As the vermouth melts (changes from a solid to a liquid) it supposedly keeps the ice at this lower temperature, preventing the ice from starting to melt until all of the vermouth has melted. Hence extending the duration of the ice.

A one litre milk carton of frozen water was placed in an Esky then a 750 mil container of frozen Vermouth placed on top. The change in temperature over time was recorded using a temperature probe placed between the two. The temperature after a couple of minutes was -8c (I.e. starting temperature). After 7 hours the temperature had risen to 6c.

The frozen vermouth, while not keeping the ice at a steady temperature appears to have kept it below 0 for 3 hours, as it gradually increased to 11c after (after a total of 12 hours), with the vermouth fully melted and the ice still having a frozen core. It stayed at 11c until the 24 hr. mark when it started to raise again, presumably because all the ice had melted.

Using 2, one litre blocks of ice, the probe place between the 2 blocks stayed below 0 for one hour, raising to 3c where it stayed for the next 20 hours. This indicates that to keep beer cans cold they need to be in direct contact with the ice.

Conclusions: The frozen vermouth kept the temperature below zero for longer - 3 hours vs 1 hour. The ice appeared to have a lower steady temperature - 3c vs 11c but maybe the prode was no longer in direct contact with the ice as I suspect 11c was the temperature of the air surrounding the ice.

• Have the beverage can in direct contact with the ice. Air is an insulator and doesn't conduct cold that well.

How cool the beer is from the fridge seems to vary from day to day and its location.

A couple of cans from far back, middle self were 2.3c and 2.9c. These contrast with another from the door shelf which was 7c. On another day the beers from the fridge were about 7c and raised to about 12c while being drank. Another factor is how long they have been in the fridge, as cooling a beer in a fridge takes longer than you probably think (refer step1)

• Beers from the fridge may be warmer than expected and could benefit from some 'ice spinning' before consumption!

Three soda beverages were cooled overnight in the fridge and then placed into a soft case Esky along with a couple of 1 litre blocks of frozen water (in milk cartons) either side of the cans. The temperature of the central soda can was graphed over time.

During the first four hours the temperature was 5c then it increased to 6.5c where it remained for the next 16 hours. The temperature then started to slowly raise, reaching 10c over the next 8 hours. This method kept the can near the 'drinking zone' for 20 hours. Wrapping a bungy around the cans of beer and cartons of ice may have kept the beers pressed to the ice and keep them cooler - as the ice melts the surrounding water is not as cold as the ice core.

Why do we cool beverages? Answer: To make them more enjoyable to drink.

At what temperature is a beverage most enjoyable? - while I normally consider 2.5c to 5c is the 'drinking zone' for beer and so most of these tests have been to get the beverage to 5c, it could be beverages are also enjoyable at other temperatures.

So, I drank some at other temperatures:

Test 1: Sparkling water at 13c - it was fine, cool and easy to drink. A good temperature to rehydrate with on a hot day.

Test 2: Sparkling water at 18c - Even when drank on a hot day, I thought it would be nicer a bit cooler.

Test 3: Sparkling water at 2c - A beverage to be sipped rather than gulped down. Enjoyable.

Test 4: Beer at 19c. Not good. This came about as I wanted to see at what temperature a beer may be after taking it from the fridge in a bottle shop and carrying it home. It was only a short trip but the beer had warmed up as it was in the outside pocket of my bag on a hot day. Don't drink an IPA beer at 19c - it's just not enjoyable.

Test 5: On another trip from the shops with a beer (double IPA 8.8%) it was found to be 13c, while it would have been nicer a bit cooler it was certainly drinkable. The higher alcohol content and overcast day probably had something to do with this.

Test 6: While on a camping trip I had a beer which was 7 c. It was fine and seemed cool enough.

Test 7: A beer at 10c after being in an Esky for 26hrs also seemed fine.

I have heard people say they 'enjoy a cold beer on a hot day'. Could it be that the temperature of the day effects people's enjoyment of the amber liquid? Recently, while on an autumn camping trip, the temperature was 14c during the afternoon and I found after drinking my first beer, cooled to 1.3c, I wasn't in a rush for another. Later in the evening, while around the campfire, the temperature had gone done to 5c and I was preferring drinking red wine to beer. So, it does seem that the environmental temperature effects your beer drinking enjoyment. My guess is any temperature above about 16c makes for good beer drinking.

On a winter camping trip, I took a beer along with no ice. Late afternoon, the air temperature had fallen to 12C while the beer temperature in the can was 15C. It was at the right drinking temperature. Looks like I enjoy beer at higher temperature in winter than I do in summer.

I wanted to take a can of beer with me on a stand-up paddle board trip. I took a cooled beer can from the fridge and gave it a cold boost by spinning it in some salt-water mushy ice cubes for 2 minutes. The can was rinsed and placed in a small frozen jell pack with a temperature probe next to it. This was wrapped in a towel and placed in a dry bag. The dry bag was attached to the deck of the SUPB. Three and three-quarter hours it was measured to be a refreshing 3c. This setup works well for keeping a single can cool for half the day.

On another Paddle Board trip, 4 pre-cooled cans were taken - a beer and 3 soda waters. The beer had been super cooled by spinning it in frozen saltwater ice. The cans were placed in a dry bag with 2 liters of frozen water in a drink carton. The dry bag was Insulated by wrapping it in a towel. After 5 hours the beverages were drank on a hot and sunny day. The results were disappointing. The super cooled beer can was 10c (not cold enough) and the soda water cans were 13c.

Freezing bottles of water to keep beer cans cold doesn't work as well as having the cans directly in ice.

Following on from the success while stand up paddle boarding, a beer was placed in a jell pack which was put in a small soft cooler, along with a frozen 2-liter carton of frozen water and taken on a camping trip. After 9 hours the beer was taken out and drank. It was 1.5 c cold.

While hiking, a cold beer placed just in a frozen gel pack, kept the beer very drinkable after 6 hours.

Wrapping a 'cold pack' around a cold beverage will keep it cold for far longer than using a stubby holder. This leads on to the 'Active Stubby holder'

While doing some catamaran sailing on a lake next to a camp-site, I set up an inflatable Esky in the shade and covered some beverages with a bag of ice purchased from the camp's store. This worked well - keeping the drinks nice and cool for the 6 hours we were there.

No water was added to the ice, after one and a quarter hours a (non cooled) can had cooled to a very drinkable 5c.

• Have cans sitting directly in the melting ice, water is a better conductor of heat/cold than air.

A 2-liter block of ice in a 2-liter carton was placed in a soft cooler and taken on a camping trip. After 9 hours the water from inside the carton was poured into a drink bottle for later use. A can of beer was spun on the ice for 5 minutes, resulting in the can cooling to 2.2 c. Three more cans were spun for 4 minutes each. I figure at least 4 more cans could have been cooled on the remaining ice but we hadn't brought that many cans... This is more cans than the small soft cooler could have held.

A friend on a camping trip had bought 4 pre-cooled cans in a soft cooler which had a couple of 600 mil frozen bottles of water in to keep the cans cool. After 9 hours one on the beers was measured to be 7 c. It was still very drinkable.

While frozen water bottles can be good at keeping beverages cold, they are not very good at cooling them down. As drinks placed directly in crushed ice will cool a lot faster due to the drinks being in direct contact.

I purchased a mini fridge for my desk. The reviews weren't promising on its cooling abilities. Turns out they were right as over 18hrs it only cooled a can of beer by 5 degrees C - from 20 C to 15 C. It may have better cooling power if a small metal cup is placed inside.

A block of ice was frozen and then groves made on the surface using the base of aluminum beverage cans which had warm water inside. This groves were linked up channels made by placing a cut off piece of a base and then heating it with a lighter. The ice with groves was supported so it would allow liquid to flow along the groves. This successfully cooled a small amount of liquid from 20 C to 5 C and could be used to cool whiskey prior to drinking.

I have read that there is a theory warm (or hot) water placed in the freezer will cool faster than cold water. I tried to test this and found hot water or water when placed in the freezer took longer than cold water to cool down to 5C. Tried 1/3 water warmed to 40c at the bottom with tap water poured above. The idea being that this temperature differential might cause some thermal circulation in the water which could result in it cooling faster than water at tap temperature. But this didn't happen.