Expired Beer: Safe To Drink Or A Sickness Risk?

Drinking expired beer will not make you sick, but it will not taste very nice. Beer is a perishable product that stales when exposed to light, oxygen, and heat, which degrade the organic compounds that make beer smell and taste great. However, the fermentation process used in brewing beer, as well as its low pH level and alcohol content, make it very resistant to spoiling. Even if a beer sits on the shelf for years, as long as it is sealed, it is unlikely to make you sick.

Pasteurisation and filtration make beer resistant to spoiling

Pasteurisation and filtration are two processes that make beer resistant to spoiling. Pasteurisation is the process of heating beer to a temperature that kills any living microbes. It was first used hundreds of years ago to prevent food spoilage and was perfected by Louis Pasteur in 1873. In the context of beer, pasteurisation involves holding the beverage at 55°C–60°C (131°F–140°F) for a short time. This process inhibits the growth of potential spoilage microorganisms and prolongs the shelf life of the beer.

Filtration is one of the oldest non-thermal methods used by breweries before filling bottles or cans. It involves passing the beer through a filter to remove unwanted particles and can be highly effective at removing microorganisms. However, some spoilage organisms may still remain in the beer after filtration, and it may also strip away flavour, aroma, body, and colour.

Both pasteurisation and filtration make beer more resistant to spoilage by reducing the presence of unwanted microorganisms. However, it is important to note that these processes may also impact the flavour of the beer.

Beer is perishable and stales when exposed to light, oxygen and heat

Beer is a perishable product, and its flavour will degrade over time. Exposure to light, oxygen, and heat will cause beer to go stale and lose its flavour. This is because light and heat can cause oxidation, which results in a papery or cardboard-like taste. UV light, in particular, can trigger a chemical reaction in certain hop compounds, creating a skunky smell and taste. This is why beer is typically packaged in brown glass bottles or aluminium cans, which block out UV rays.

Oxygen also interacts with the compounds from malt, yeast, and hops, causing oxidation and a disappointing taste. Even with advanced techniques and new technology, a tiny amount of oxygen will still make it into a can or bottle, so some change in flavour is inevitable. Once a bottle or can of beer is opened, oxidation accelerates, and the beverage will spoil if left out for too long.

Heat speeds up oxidation, so storing beer in a refrigerator is essential to maintaining its freshness. Major changes in temperature, such as transferring beer from an ice-cold cooler to a hot car, can also negatively impact its flavour.

Beer is unlikely to make you sick even if it's been years

However, it's important to note that the taste of beer will change over time. Beer is a perishable product that stales when exposed to light, oxygen, and heat, which degrade the organic compounds responsible for its flavour and aroma. The volatile aromas from hops, for instance, tend to dissipate, resulting in a loss of the characteristic hoppy aroma found in IPAs.

Additionally, the speed of these chemical reactions depends on the alcohol content of the beer and how it's stored. Refrigerating beer or storing it in a cool, dark place slows down the ageing process. Beers with higher alcohol content, such as barley wines and imperial stouts, tend to have a longer shelf life and are sometimes brewed with ageing in mind.

While drinking expired beer is generally safe, there are a few rare situations where it's best to discard it. If the beer has lost its fizz, it indicates that the seal was broken, and the flavour will be significantly altered. Moreover, if a non-tangy or non-acidic beer develops a vinegary taste, it's a sign that bacteria have contaminated it, and it should be thrown out.

In summary, while beer can be safely consumed past its expiration date, the taste will deteriorate over time. To maintain optimal flavour, it's best to follow the recommended storage conditions and consume beer within a few months of purchase or before its best-by date.

Beer that's lost its fizz or has a vinegary taste should be thrown out

Drinking beer that has lost its fizz or has a vinegary taste is unlikely to make you sick, but it's probably not going to taste great, either.

Flat beer is caused by a lack of carbonation, which can be due to several factors, including incorrect temperatures, an incorrect seal, or dead yeast. Beer that has gone flat will have a disappointing papery taste.

If your beer has lost its fizz, you can try to recarbonate it by increasing the temperature, adding sugar, or pressurising it. You could also try agitating it or forcing carbonation into the beer using a tool like a SodaStream machine. However, keep in mind that this may not always be successful, and it's often better to just avoid drinking flat beer.

Regarding vinegary-tasting beer, this is most likely caused by an acetobacter infection. If your beer has a vinegary taste, it's best to throw it out, as it's a sign that bacteria have gotten in.

In summary, while drinking expired beer is usually safe, it's not worth risking your taste buds on beer that's lost its fizz or has a vinegary taste.

Beer should be stored in a cool, dark place

Natural light, in particular, is beer's worst enemy. Beer contains hops, a species of plant that infuses the brew with delicious scents and hints of bitterness. When ultraviolet rays strike beer, they interact with acidic hop compounds called humulones, creating a nasty chemical reaction. This produces a noxious chemical similar to what a skunk sprays when it's frightened. That's why some people refer to bad beer as 'skunked'. The more prolonged the UV blast, the greater the skunking. Even just half an hour spent outside in direct sunlight will hurt your beer.

The temperature at which beer is stored is also important. The colder the beer, the longer it will stay fresh. However, beer can stand up to modest temperature swings. For example, if you buy cold beer and stick it in your basement, or if you chill a bunch for a party and then let it warm up again, that won't ruin it. The real threat is long-term exposure to high temperatures. Even a single day of exposure to high temperatures could make your beer go stale quickly.

So, to keep your beer tasting fresh, store it in a cool, dark place.

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