Cold Beer Warming Up? Here's What To Do

It's a common misconception that cold beer will go bad if it's allowed to warm up and then be cooled down again. This is a pervasive myth, and in reality, the flavour of the beer will remain unchanged. However, it's important to note that extreme temperature fluctuations, such as going from freezing to 100+ degrees Fahrenheit, should be avoided as this may cause the beer to explode. Additionally, exposure to very warm temperatures for extended periods can negatively impact the beer's flavour.

Beer warming up and cooling down again will not ruin it

It is a common misconception that warming up and cooling down beer will ruin it. This is a myth. Beer warming up and cooling down again will not ruin it.

The Truth About Skunking

Skunking is caused by light interacting with a chemical compound found in hops. It has nothing to do with temperature. Skunking is, therefore, a result of lightstrike, not temperature fluctuations.

Temperature Fluctuations

Temperature does affect beer. However, it is not temperature cycling that destroys beer, but exposure to extreme temperature fluctuations and warm temperatures over an extended period of time. For example, keeping beer at room temperature can reduce its shelf life from nearly six months to only a few weeks. Very warm temperatures can affect its flavour in a matter of days.

Beer Import

If temperature cycling "skunked" beer, then all beer imported from Europe would be destroyed before it was bought. On its long journey across the Atlantic, this beer has likely changed temperatures several times, yet it is easy to find non-skunked imported beer.

Extreme heat can ruin beer

It is a common misconception that beer will "skunk" if it warms up after being refrigerated. This is a myth. Beer can be warmed and then cooled again without any ill effects. In fact, beer likely goes through several cold-warm-cold cycles on its journey from the brewery to your glass.

However, extreme heat can indeed ruin beer. Heat speeds up the process of oxidation, which causes some beers to develop a stale, cardboard-like flavor, accompanied by a note of sherry. Malt-forward beers can develop a sweet, bready, toffee-like flavor. The "hoppiness" of a beer will also dissipate under extreme heat, with any piney, citrusy, or floral hop aromas disappearing.

The effects of oxidation increase exponentially as the temperature of the beer goes up. A beer sitting at 60 degrees Fahrenheit will retain its original flavor for much longer than a beer sitting at 90 degrees Fahrenheit. Therefore, it is best to avoid exposing beer to very warm temperatures, especially for extended periods.

In summary, while it is not true that beer will be ruined if it warms up after being refrigerated, extreme heat can indeed have a detrimental effect on the flavor of beer. To preserve the freshness and quality of your beer, it is best to avoid exposing it to high temperatures for prolonged periods.

Light is the main cause of skunky beer, not temperature

It is a common misconception that temperature changes will "skunk" beer. In reality, light, specifically UV light, is the main cause of skunky beer. This is because certain light wavelengths, between 350 and 550 nanometers, cause a chemical reaction in the hops that creates the "skunk" flavour.

The sun is the biggest culprit when it comes to skunking beer, as it emits the most light in the skunk-causing wavelength range. However, artificial lights can also cause beer to go skunky, especially fluorescent lights, which emit light at 434 nm, firmly in the danger zone. Incandescent and halogen bulbs are safer, as they emit negligible UV light, and LED lights emit almost purely visible light.

The colour of the beer and the glass bottle also play a role. Dark beers absorb a broader spectrum of light, so lighter beers are more prone to skunkiness. Similarly, brown glass absorbs the most skunk-causing wavelengths, whereas clear, green, and blue glass allow some or all of these wavelengths to pass through.

While temperature changes do not cause beer to become skunky, extreme temperature fluctuations and exposure to very warm temperatures can negatively affect a beer's flavour. Heat speeds up the oxidation process, causing some beers to develop a stale, cardboard-like flavour, and others to take on a sweet, bready, or toffee-like taste. Additionally, the "hoppiness" of a beer will dissipate in very hot temperatures.

Beer is best preserved when kept cold

That being said, higher-than-normal temperatures over an extended period can negatively impact a beer's flavour. Heat speeds up the process of oxidation, which can cause some beers to develop a stale, cardboard-like flavour, along with a note of sherry. Beers with a higher proportion of malt can develop a sweet, bready, toffee-like flavour. Additionally, the "hoppiness" of a beer will also be affected by extreme heat, with the bitterness of hops remaining but any piney, citrusy or floral aromas disappearing.

The effects of oxidation increase exponentially as the temperature of the beer rises. Therefore, a beer kept at 60 degrees Fahrenheit will retain its original flavour for much longer than a beer sitting at 90 degrees Fahrenheit.

It is worth noting that it is not temperature cycling that destroys beer, but rather exposure to warm temperatures over a prolonged period. Keeping beer at room temperature can reduce its shelf life from almost six months to just a few weeks, and exposing it to very warm temperatures can impact its flavour within a couple of days.

Beer at room temperature will have a shorter shelf life

Beer that is kept at room temperature will have a shelf life of only a few weeks, as opposed to nearly six months if it is kept cold. Exposing beer to very warm temperatures can affect its flavour in a matter of days. The ideal temperature for beer is around 60 degrees Fahrenheit; at this temperature, beer will retain its original flavour for longer than if it were kept at 90 degrees Fahrenheit.

Oxidation, caused by heat, will make some beers develop a stale, cardboard-like flavour, with notes of sherry. Malt-forward beers can develop a sweet, bready, toffee-like flavour. The "hoppiness" of the beer will also dissipate with extreme heat.

Therefore, while warming and then cooling beer will not make it go bad, beer kept at room temperature will have a shorter shelf life and its flavour will be affected.

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