Temperature and its effect on packaged beer

People often ask how long a can or bottle of beer will last if they buy it now. It’s a bit of a loaded question because there are many variables to consider when trying to provide an accurate answer. But, it is asked frequently because there are a number of misconceptions and myths floating around. As an example, we will have people request room temperature cans of beer for sale because they think beer may degrade faster if it is cooled and warmed through a number of cycles. Starting out warm isn’t the key.



Let’s walk through how we package beer. All MadTree beers are packaged at about 35 degrees for a few reasons. First, after the fermentation and clarification process, beers are transferred to the brite tank to be quickly cooled in preparation for carbonation. The cooler temperature makes it easier for the still beer to absorb the CO2 for carbonation. Second, the colder temperature means less CO2 will come out of suspension during packaging. As beer warms, more CO2 is released from beer creating a foamy mess. Third, the colder temperature means the beer will stay brewery fresh for a longer period of time when it is held at a constant low temperature.

The 3-30-300 Rule

There is a great rule of thumb that has been devised from research from the macro breweries (you can’t argue with their science, even if you don’t like their beer): the 3-30-300 rule.

Quite simply, a beer will degrade in a similar manner after 3 days at 90 degrees – like in the trunk of your car in the spring/summer. 30 days at 72 degrees – room temperature on a retail shelf. Or, 300 days at 38 degrees – refrigerated.

Fluctuations in temperature may certainly accelerate the aging of a beer but when you are looking at short-term storage, it really isn’t much of an issue – as long as you keep it out of the trunk of your car!

Again, this is a rule of thumb as different beers with different ingredients may degrade faster or slower under these conditions. But, it is one reason why we package and store beer at cold temperatures.

While it is certainly reasonable to serve beer styles at a variety of temperatures, for packaging and storage purposes it is appropriate to keep it cold for the greatest stability.

The Frozen Glass Incident

And while we are on the topic of temperature let’s talk about frozen beer glasses. Yeah, you’ve probably heard this one before but it’s worth repeating in hopes that more folks will get the message. In short, a great idea to keep a beer cold is actually a great way to ruin a beer. The ice crystals on the glass will cause you to pour a glass full of foam. This means you won’t get that nice beer with an appropriate sized head that unlocks all the great aromas– thus, impacting the overall sensory experience. The aromas (scent is half of what you taste) will be suppressed so you don’t get the full experience.

Next, the water used to coat the glass to create the frost may be contaminated with chlorine (think tap water) or worse it will pick up dirt, bacteria, food oils and aromas, and other gross particles that may be floating around the freezer where it is stored. As that ice melts, all those nasties are released into your beer.

Lastly, dropping the beer temperature to near freezing temperatures will numb your tongue/taste buds and render you unable to taste the more nuanced and delicate flavors of a well-crafted beer. That hop bomb goes from mind-blowing to meh, simply due to the serving temperature.