It’s probably not something you think about every day, but there’s a chance you’ve opened a bottle of beer before and wondered why it smells like weed.
It turns out you’re not the only one who’s thought it.
Whether you choose to believe it or not, according to LADbible, there’s an actual scientific reason behind the phenomenon and it’s all because of a little-known chemical reaction that takes place in the bottle when the alcohol reacts with the light of the UV rays.
Back in 2001, a group of scientists led by University of North Carolina professor of chemistry Malcolm Forbes PhD found that a reaction takes place when beer that specifically contains hops is left in the sun.
Professor Forbes even suggested that this is one of the main reasons why Corona – the beer that is the most common culprit for smelling ‘skunky’ – is usually served with a lime wedge.
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“Corona is marketed extremely cleverly,” he admitted.
So, what actually is the science behind it then? And to what extent should we believe it?
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Well, after research into the phenomenon, Professor Forbes and his team published their findings in Chemistry: A European Journal and explained that they found that flavour compounds known as iso-alpha acids are brought forth when the beer is brewed, and that’s actually what gives the beer its distinctive taste – but when those compounds are over-exposed to sunlight, they are turned into free radicals and that makes them highly reactive.
A reaction takes place when beer that specifically contains hops is left in the sun / Credit: Pixabay
When those free radicals – which are atoms or molecules that have unpaired electrons – mix with protein, they form another molecule called 3-methyl-2-butene-1-thiol, and it’s this that produces an extremely potent cannabis scent.
It’s so strong that even one part per billion can be picked up by the human nose.
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“Hops help flavour beer, inhibit bacterial growth, and are largely responsible for the stability of the foam in the head,” Professor Forbes explains.
“[But] hops, however, are light-sensitive, and the three main compounds in them identified as being light-sensitive are called isohumulones [so] when attacked by either visible or ultraviolet light, these break down to make reactive intermediates known as free radicals that lead to the offensive taste and skunky odour.”
As well as serving with lime, most beer bottles are also made brown or green to combat this process.
But that doesn’t mean they won’t turn if left in the sun for too long, so it’s still best to keep the beer inside and store it in the dark.
Featured Image – Shot Stash
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Two North West cities named among the ‘noisiest’ in the UK – including Manchester
Emily Sergeant
A new analysis has revealed a list of the noisiest cities in the UK, and two Greater Manchester locations are in the top five.
From blaring sirens and car horns, to house parties, barking dogs, and loud neighbours, escaping the noise of a city can feel almost impossible – even in your own home.
No matter whether you live in the hustle and bustle, or you’re out in the sleepier suburbs, noise can keep you up at night, disturb your peace, and lead to frustration. But just how loud are Greater Manchester’s cities compared to the rest of the UK? In a bid to get to the bottom of it, Alpine Hearing Protection has done some research to compile a top 10 list.
And both Salford and Manchester have found themselves not just within the top 10, but within the top five… and to make matters worse, Salford has actually claimed the number one spot.
The reason Salford has found itself at the top of the list, according to the research, is because it sits at the intersection of several major transport and urban hubs, with major motorways running through or around the city including the M60, M61, and M62.
Major rail routes also run through the city – including via Salford Crescent – which sees 16 million passengers every year, and also leads to Manchester Airport.
Top 10 noisiest cities in the UK
Salford
Portsmouth
Manchester
Southampton
London
Leeds
Stoke-on-Trent
Wakefield
Newcastle upon Tyne
Bradford
Parts of Salford are also very built-up, making pockets of the city noisy – especially in the concentrated centre where traffic, construction, nightlife and commercial activity get loud.
And of course, like any growing city, construction noises have been noted as ‘particularly bothersome’ for residents where major developments are springing up.
Manchester is third on the list of noisiest cities, due to many of the same reasons as Salford.
But the difference being that Mancunians are noted as one of the many reasons why the city is so loud – with residents making 5,301 noise complaints across Manchester between January 2024 and January 2025, and Hulme identified the loudest area with 304 complaints.
As well all know, Manchester is also home to many universities, which brings an active nightlife scene to the region, especially in the city centre, and in recent FOI data, it was revealed that the University of Manchester saw 2,049 noise complaints in the last five years.
Motorists warned of common winter driving habit that could land them with annoying fines
Emily Sergeant
With the temperatures drastically dropping now as we head into winter, motorists are being warned against a common driving habit.
On a wintry morning when the windscreens are frozen and your hands are equally as frozen too, it’s pretty common for drivers to start the engine, turn the heater right up, and remain stationary for several minutes to warm the car up before setting off on their journey… but did you know that doing this could see you, inadvertently, fall foul of the law?
That’s right – as ridiculous as it sounds, leaving your car engine running ‘unnecessarily’ while parked on a public road is illegal.
And to make matters worse, the rules on ‘engine idling’, as it’s known, apply regardless of whether the driver is using the heating, waiting for someone, or simply sitting in the vehicle.
Known as a stationary idling offence, Rule 123 of the Highway Code states that drivers must not leave a vehicle’s engine running unnecessarily while it is stationary on a public road, and according to the rule, a fixed penalty of up to £80 can be issued, right there and then.
Motorists are being warned of a common winter driving habit that could land them with annoying fines / Credit: PickPik | Wikimedia Commons
Fines will only be handed out if a motorist is stopped by a police officer who asks them to switch the engine off, and they fail to comply.
“However tempting it might be to sit in a vehicle with the engine running and the heater on to warm up, we strongly advice against it,” commented RAC senior policy officer Rod Dennis.
“As well as polluting the air and wasting fuel, drivers who leave their engines idling unnecessarily on a public road also risk an on-the-spot fine of £80. On cold mornings, the best approach is to clear any ice or snow properly and ensure windows are fully de-misted before setting off, then get on your way and let the car warm you up.”
There are some exceptions to the rule, however, as keeping the engine running is permitted in certain circumstances.
This includes when a vehicle is stationary because of traffic conditions, when the engine needs to run so a mechanical fault can be investigated, or if certain work is being carried out on the side of the road.
Emily Sergeant -
23rd August 2021 
