Beer Storage: Opened Beer, Refrigerated – Still Drinkable?

Beer is a beloved beverage for many, but what happens when you don't finish the whole bottle? Can you simply recap it and stick it in the fridge for later? The answer is: it's not that simple. Beer is fragile and can quickly lose its quality after being opened. While you can still drink it after a day or two, its flavour will be far from pleasant.

Several factors affect how long an open beer will last. These include temperature, sunlight exposure, and oxygen exposure. Storing beer at typical refrigerator temperatures of 35°F to 46°F can help prolong its freshness. Additionally, keeping beer away from direct sunlight and heat is crucial, as UV rays can cause flavour deterioration.

Oxidation is another concern, as it can alter the beer's flavour and cause it to go flat. To minimise oxidation, it's important to seal the bottle or can tightly after opening and consume it promptly.

While drinking stale beer may not make you physically ill, it can leave you with an unpleasant taste in your mouth and a stomachache. So, if you're planning to save that half-drunk beer for later, make sure to store it properly and consume it within a day or two for the best experience.

Beer's shelf life

Beer shelf life depends on several factors, including temperature, container, time, bottling, and the variant of the beer.

Temperature

Beer should be stored in a cool, dry place, with temperatures between 35 and 55 degrees Fahrenheit (2 to 13 degrees Celsius). Avoid areas prone to temperature fluctuations, such as near windows or heating vents. If you have a refrigerator, always store your beer in it. The cold temperature will slow down the beverage's flavour degradation, giving you more time to enjoy it.

Container

The container also matters. Beer stored in a bottle is at a higher risk of exposure to oxygen than canned beer. Beer in clear or green bottles is also more susceptible to light exposure, which can create a chemical reaction in the beer, breaking down its flavour components and causing it to smell and taste like skunk spray. Brown bottles and aluminium cans are effective at blocking out light.

Time

Beer has a shorter shelf life once it has been opened. A sealed beer can typically stay at optimal quality for about 4 to 6 months when stored at room temperature, but once opened, it is only fresh for 1 to 3 days. You can still drink it after this time, but its taste will be far from pleasant.

Bottling

Bottled beer should be stored upright to minimise contact with oxygen and avoid air leaks.

Variants

The type of beer also affects its shelf life. Lighter beers, such as pale ales, wheat beers, lagers, and IPAs, are best consumed within 3 months of packaging. Heavier beers like stouts and porters have a longer shelf life of about 6 months.

Oxidation and loss of carbonation

Oxidation

Oxygen exposure can have negative effects on beer quality due to its oxidative properties. When oxygen comes into contact with beer, it can cause oxidation, degrading the beverage's flavour and changing its colour. This can lead to off-flavours such as a cardboard-like taste, a stale or papery aroma, or a loss of hop aroma and flavour. Oxidation can also accelerate the breakdown of hop-derived compounds, resulting in a loss of the desired hop characteristics of the beer.

Oxygen exposure can also contribute to haze formation in beer. Haze refers to the cloudiness or turbidity that may appear in beer due to the presence of certain proteins and polyphenols. Oxidation reactions can lead to the polymerisation of these compounds, causing haze to develop and affecting the beer's appearance.

Furthermore, oxidation can cause colour changes in beer. Lightstruck flavours, commonly known as "skunked" flavours, can arise when beer is exposed to oxygen and ultraviolet light, leading to a chemical reaction that alters the beer's colour and produces off-flavours.

Loss of Carbonation

Loss of carbonation is another factor that affects the quality of an open beer. When a beer bottle is opened, carbon dioxide begins to escape, and the beer will start to go flat. The beer will lose its carbonation, flavour, and freshness within 24-48 hours of being opened. Refrigerating an open beer can slow oxidation and preserve its freshness for a little longer, but the overall quality and taste may still be impacted as oxygen exposure continues even in cold temperatures.

Proper storage

The best way to store beer is in a cool, dark place. Beer is best kept in a refrigerator, where it will remain at its optimal quality for up to eight months. If you don't have a refrigerator, store it in a cool, dry place with temperatures between 35 and 55 degrees Fahrenheit (2 to 13 degrees Celsius). Avoid areas with temperature fluctuations, such as near windows or heating vents. Keep the beer away from light and heat, and store it upright rather than on its side to minimise the surface area exposed to oxygen.

If you're storing beer in a bottle, screw the cap back on tightly as soon as you've finished pouring to prevent oxidation and loss of carbonation. If it's a screw-top glass bottle, you can store it upside down in the refrigerator to prevent pressure escape.

For beer in a keg, keep it in a cool, dry space away from other foods. Avoid freezing the keg, and don't move it around too much to prevent excess foam when you tap it.

Beer in a growler should be stored upright in a cool, dark space. Once opened, it will stay fresh for up to 36 hours.

Home-brewed beer should be stored in glass bottles or kegs. Bottles are affordable and easy to store, but they require thorough sanitisation between brews. Kegging takes longer but provides more control over carbonation.

If you want to age your beer, store it in a cool, dark place with minimal movement. The ideal temperature is around 10 degrees below the beer's fermentation temperature.

Beer has a shelf life of around two days before it loses flavour significantly. However, it can be salvaged and stored for up to a week if chilled from the start or kept in an airtight container. Beer kept at cool temperatures slows the oxidation process, extending its shelf life.

Once opened, beer should be resealed with an airtight cap or stopper to reduce oxidation and prevent carbonation loss. Beer stored in this way will usually last for three to four months.

Signs of Spoilage

Several signs indicate that your beer has gone bad:

• No "psst" noise when you open it, coupled with a lack of white foam climbing to the top
• A flat taste, even if there is foam and a noise when you open it
• A faded or discoloured label, or a dusty bottle
• Sediment at the bottom of the bottle
• Leakage around the bottle's opening, which may indicate that the beer was subjected to extreme heat
• An unpleasant flavour, a musty smell, or visible mould
• Cloudiness, which may indicate bacterial contamination
• An unusual taste, such as metallic, sour, or cardboard-like flavours
• An unpleasant odour, such as skunk or urine, which may indicate bacterial growth

Signs of spoilage

Beer spoilage is caused by unwanted microorganisms, including wild strains of yeast and bacteria, that alter the beer's flavour, aroma, or appearance. While most of these microorganisms are not harmful to health, they can make the beer unpleasant to drink. Here are some signs of spoilage to look out for:

Unpleasant Odours

An unpleasant smell, such as skunk, urine, rotten eggs, or vinegar, indicates the growth of bacteria or other microorganisms in the beer. Even if you can tolerate these odours, consuming the spoiled beverage is not advisable.

Strange Taste

Strange or unusual tastes, such as metallic, sour, bitter, or cardboard-like flavours, are clear signs of spoilage. These off-flavours usually result from bacterial contamination or extended exposure to oxygen. If you notice any strange tastes, it is best to discard the beer.

Cloudiness or Haze

Cloudiness or haze in the beer can be a sign of bacterial contamination. When bacteria are present, they can cause proteins and other compounds to clump together, leading to a cloudy appearance. However, note that not all cloudy beers are spoiled, as some craft beers have a hazy appearance for flavour and texture.

Mould Growth

While it is uncommon for unopened beer to develop mould due to its alcohol content and low pH level, issues during the bottling or canning process can result in mould growth. If you see any signs of mould, do not consume the beer.

Excessive Bitterness

Beer spoilage can also result in excessive bitterness. This is often caused by the growth of microorganisms such as Lactobacillus, Pediococcus, and Brettanomyces, which can produce off-flavours.

Flatness

Flat beer is characterised by a lack of carbonation, resulting in a lack of distinct bitterness and sharpness. This can occur when beer is left open for too long or exposed to sunlight, as it triggers a chemical reaction that breaks down its taste components.

Musty Smell

A musty or "horsey" smell can indicate the presence of wild yeast strains, such as Brettanomyces bruxellensis, which can create excess phenolic compounds and carboxylic acids.

Rope-like Consistency

Some bacteria, such as Pediococcus, can form beta-glucans, giving the beer a "rope consistency" and a buttery taste.

Rancid Taste

Rancid or "skunky" tastes can be caused by gram-negative bacteria, which produce butyric acid and mercaptans.

Vinegary Flavour

Vinegary off-flavours can be produced by gram-negative bacteria, which oxidise ethanol into acetic acid.

Other Off-Flavours

Other off-flavours to look out for include green apple, cooked vegetable, clove-like, medicinal, fruity, barnyard, and horse blanket tastes. These can be caused by various bacteria and wild yeast strains.

It is important to note that spoilage can occur even when the beer is refrigerated, and it is recommended to consume an opened beer within 1-2 days for optimal flavour. Additionally, proper storage, such as keeping the beer sealed, upright, and in a cool, dark place, can help extend its shelf life.

Beer's shelf life extension

Beer's shelf life depends on a variety of factors, including the type of beer, its alcohol content, and how it is stored. Here are some tips to help extend the shelf life of your beer:

Find the Perfect Storage Spot

It is recommended to store beer in a cool, dry place with temperatures between 35 and 55 degrees Fahrenheit (2 to 13 degrees Celsius). Keep the beer away from areas prone to temperature fluctuations, such as near windows or heating vents. Exposure to UV rays can also cause the beer to go bad, so it is best to store it in a dark place or in a refrigerator.

Keep the Beer Sealed and Upright

Properly sealing your beer bottles or cans after opening can help prevent oxygen exposure, which can cause the beer to go bad faster. Storing the beer upright also minimizes the surface area exposed to oxygen, preserving its freshness.

Avoid Temperature Fluctuations

Exposing beer to rapid temperature changes can negatively impact its quality and taste. It is best to avoid freezing and thawing beer, as this can affect its carbonation levels and facilitate spoilage.

Use Resealable Containers

If you plan on drinking a beer over multiple sittings, consider using resealable containers like growlers or kegs. This will help slow the oxidation process and maintain the beer's freshness.

Add Sterile Beer Salts

Adding a few drops of sterile beer salts to the beer can help create an environment where germs cannot thrive. This is especially beneficial for stronger alcoholic brews, which are more prone to oxidation.

By following these tips, you can help extend the shelf life of your beer and enjoy it for a longer period of time. However, it is important to regularly check for signs of spoilage, such as an unpleasant flavor, a musty smell, or visible mold.

Frequently asked questions