Skunked Beer: Is It Safe To Drink?

Skunked beer is a well-known issue for beer drinkers and brewers alike. It occurs when bottled beer is exposed to direct sunlight or artificial light, resulting in an unpleasant taste and smell reminiscent of a skunk's spray. While it may be unappetizing, is it safe to drink skunked beer? The answer is yes, it's technically safe to consume. Skunked beer is the result of a chemical reaction between the hops in beer and light, specifically ultraviolet light, which affects the flavour but not the safety of the beverage. However, drinking a skunked beer is not a pleasant experience, and there are ways to avoid it, such as choosing canned or kegged beer over bottled beer or storing beer in dark and cool places.

What does skunked beer taste like?

Skunked beer is caused by exposure to UV rays or blue light, which can only reach the beer through glass bottles. The light causes a chemical reaction in the hops, resulting in a compound called 3-MBT, which gives off a skunk-like flavour and aroma. The longer the beer has been exposed to light, the stronger this flavour will be.

So, what does skunked beer taste like? Randy Mosher, in his guide *Tasting Beer*, describes the perception of methyl or isopentyl mercaptan (skunking) as "skunky or rubbery". The Cicerone program describes it as "musty, [and] can be similar to burned rubber or cat musk". One source says it tastes like "an offensive, sulphuric, all-pervasive taste", with a "manky, wet-dog aspect". Another says it's like "burnt rubber, body odour combined with burnt popcorn, sour coffee, or certain strains of aromatic marijuana".

If you want to know what skunked beer tastes like, you can create it at home. Pour a hoppy beer from a can (so it's not already skunked) into a clear glass and leave it in direct sunlight for 15 to 30 minutes. Then, taste it and compare it to the rest of the beer that you kept in a dark place.

How to tell if your beer is skunked

Skunked beer is bottled beer that has undergone a chemical reaction due to exposure to ultraviolet or artificial light. The resulting compound, 3-methyl-2-butene-1-thiol (MBT), smells like a skunk's secretion.

Skunked beer is not unsafe to drink, but the chemical reaction affects its taste and smell. It may smell like burnt rubber, a musty basement, or wet cardboard.

• Check the packaging: Skunking mainly occurs in bottled beer, especially those in clear, green, or blue glass bottles. Brown bottles offer more protection against UV rays, and cans are the most effective at blocking light.
• Observe the storage conditions: If the beer has been stored in direct sunlight or under harsh lighting, it is more likely to be skunked.
• Smell the beer: The most distinctive sign of skunked beer is its strong skunk-like odour. If it smells like burnt rubber, a musty basement, or wet cardboard, it is likely skunked.
• Taste the beer: Skunked beer may have an unpleasant taste, but it is not harmful to consume. If you detect a slight difference in taste, it could be due to other factors affecting the beer's quality.
• Compare with a fresh sample: If you have access to a fresh bottle of the same beer, compare the smell and taste to the one in question.
• Try a different beer: If you ordered a beer at a bar and suspect it might be skunked, try ordering a different beer to see if there is a noticeable difference.

To avoid skunked beer, it is recommended to choose canned beers or beers bottled in brown glass. Store your beer in a dark, cold place, and if drinking outdoors, use a cooler with a lid to minimise light exposure.

Is it safe to drink skunked beer?

Skunked beer is a result of a chemical reaction between the hop flavour compounds in beer and ultraviolet light. Beer that has been exposed to direct sunlight or artificial light will have a sulphuric taste and smell similar to a skunk's spray.

Skunked beer is safe to drink and will not make you sick, unless you drink many over a short period of time, but this is due to inebriation and intoxication rather than the skunking. The alcohol content of a beer remains completely unchanged by the light-strike reaction. The chemical reaction only affects the profile of the beer.

However, it is unpleasant to drink due to its skunky taste and smell. Skunked beer may smell like burnt rubber, a musty basement, or wet cardboard. It has also been described as having a slightly manky, wet-dog aspect to it.

To avoid skunked beer, you can opt for canned beer or beer in brown bottles, as these are better at blocking out UV light. If you are storing or displaying beer, keep it away from direct sunlight and in a dark, cool place.

How to prevent skunking

Beer is susceptible to skunking, a chemical reaction that gives it a bitter, putrid taste and smell akin to a skunk. Skunking is caused by exposure to UV rays, which is why it only happens in bottles. The complex chemical reaction involves blue spectrum and ultraviolet light messing with compounds produced by hops, called isohumulones or iso-alpha acids. The result of this sunlight-induced reaction is the creation of a compound called 3-MBT, which gives off the skunk flavour.

• Keep bottled beer out of direct sunlight, especially if it is in a green or clear glass bottle. Brown bottles offer better protection against UV rays, but even they can let in enough light over time to skunk the beer.
• Store beer in the shade, and keep the cooler lid shut.
• Choose beers packaged in aluminium cans or brown bottles, as these containers are most effective at keeping light out.
• Avoid storing beer in hot environments, as heat increases the rate of oxidation, which can make the beer taste stale or like cardboard.

What to do with skunked beer

Skunked beer is a common problem, especially in the summer months when enjoying a cold beer in the sun is a popular pastime. But what do you do if your beer has been skunked?

Firstly, it's important to know what skunked beer is and how to identify it. Skunked beer occurs when a beer is exposed to direct sunlight or ultraviolet light, causing a chemical reaction in the hops that results in an unpleasant sulphuric taste and smell, similar to that of a skunk's spray. This process is called light-strike, and it can happen within seconds of the beer being exposed to light. The longer the exposure, the more likely the beer is to become skunked.

If you're drinking bottled beer, clear, green, or blue glass bottles are more likely to result in skunked beer as they don't block out the light. Brown bottles offer better protection, blocking out light under 500nm in wavelength, while green glass only blocks out light under 400nm. The best option for avoiding skunked beer is to choose cans, which block out all light.

Now that we know what skunked beer is and how it happens, let's get to the main question: what do you do with skunked beer? Here are some options:

• If you're in a pub or bar and you're served a skunked beer, you can ask for another one. However, if the beer is skunked, it's likely due to incorrect storage, so ordering the same beer again may not be the best idea. Instead, opt for something on tap or served in a brown bottle.
• If you're drinking at home and you realise your beer is skunked, you have a few options. You can choose to drink it anyway, especially if you're able to desensitise your olfactory system to the skunked smell by sniffing it a few times. Or, you can pour it out and try to avoid making the same mistake again by storing your beer in a dark, cool place like a basement or fridge.
• Another option is to chug the beer to avoid the bad taste. This may not be the most enjoyable option, but it will get the job done!
• Finally, remember that skunked beer is still alcoholic and will not make you sick (unless you drink too much, of course). So, if you're desperate, you can always try to power through and ignore the unpleasant taste and smell.

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