The Sourest Sweets in the UK: Ranking the Best Sour Sweets by Intensity
Some sweets are built to make you wince. Sour sweets coat themselves in food acids that hit the tongue with a sharp, eye-watering pucker before mellowing into something sweeter, which is exactly what their fans love about them. There is no official scale for sourness the way there is for chilli heat, so any ranking comes down to the acids used, the makers' claims and the verdict of those who have tried them. With that in mind, here are the sourest sweets you can get hold of in the UK, from the gentle end of our sour sweets range up to the genuinely fierce.
Five Key Facts About the Sourest Sweets
- There is no scale for sourness, so rankings rely on the acids used and on taste rather than a single measured number.
- The sour kick comes from food acids, mainly citric and malic acid, with malic giving the sharpest, longest-lasting hit.
- Barnett's Mega Sours and Mr Simms Black Death are the British heavyweights, both often called the most sour of all.
- Toxic Waste and Warheads are the famous challenge brands, built around an intense coating that fades to a sweet centre.
- Sour Patch Kids and sour gummies have a less intense sour taste and mark a great place to start on the sourness scale.
How Sourness Actually Works
The pucker in a sour sweet comes from food acids in the coating, and it is the same kind found in fruit. Citric acid, the sourness in lemons, gives a distinct and immediate tang. Malic acid, on the other hand, is sharper and lasts longer, making it a more common ingredient in sweets designed to have more of a sour punch. It is not uncommon for a little tartaric acid to be added as well, and the more acid that is packed into the coating, the more intense a sour taste you will get.
When it comes to the hardest sweets, the coating can take around thirty seconds to dissolve fully, and that is the part that makes your eyes water before you start to taste any of the sweetness. Even though there is no set scale for sourness, the acids used and the verdict of those who have tried them form a very loose ranking rather than a precise figure.
Ranking the UK's Sourest Sweets
Starting at the top for the most intense sour flavour, these are the sweets that have built their reputation on sheer sour intensity.
| Sweet | Sourness | The lowdown |
|---|---|---|
| Barnett's Mega Sours | Extreme | British boiled sweets, often claimed to be around three times sourer than the challenge brands |
| Mr Simms Black Death | Extreme | A British coal-black lemon sweet with a cult following |
| Toxic Waste | Very high | The hazardous-waste drum, a long, slow-building sour burn |
| Warheads | Very high | The original challenge sweet, a sharp hit that fades to sweet |
| Sour Patch Kids | Medium | A lighter sour dusting before a soft, sweet gummy |
| Sour Haribo and Chewits Xtreme | Mild to medium | A gentler tang, a good starting point |
As some of the most potent and memorable of all, two British sweets sit at the very top of the list. The first, Barnett's Mega Sours, traditional boiled sweets made in copper pans, are frequently called the world's most sour sweet, with some claims putting them around three times sharper than the big challenge brands. The second, Mr Simms Black Death, a coal-black lemon sweet, has a similar cult reputation. Just behind them sit the famous challenge brands: Toxic Waste, with its hazardous-waste drum, and Warheads, the original face-twisting hard candy. They all follow the same arc, a brutal opening that softens into sweetness as it goes.
Stepping Down to Medium and Mild Sours
Because some of the sourest sweets are so intense, they are not always as enjoyable for those less used to the taste, but there are plenty of milder options that let you enjoy a sour kick without being overwhelmed. Sour Patch Kids are one of the most accessible, with a light sour dusting that quickly turns into a soft, sweet gummy, and the extreme box turns that up a notch while staying manageable.
British favourites like Chewits Xtreme bring a manageable apple sourness, while sour Haribo and Mike and Ike are more tangy than full-on sour. If you prefer your sour in gummy form, sour worms and bears are about as easy-going as the category gets. It makes a good ladder to climb: start mild, work up, and you will find your level before you reach the drum-packaged end. The milder Sour Patch shelf is a comfortable place to begin.
Be Careful Not to Consume Too Many at Once
Sour sweets are intense by design, and while that is the fun of them, the strongest are best enjoyed a few at a time rather than by the handful. The sharp acid coating is what makes the extreme sweets like Toxic Waste so fierce in those first few seconds, so it pays to go gently with a new one and let the sweetness come through. The hardest of them are very acidic and several carry age warnings, so they are really aimed at older children and adults rather than little ones. Treated with a bit of respect, the sour side of the sweet aisle stays one of the most entertaining around.
Frequently Asked Questions About UK Sour Sweets
What is the sourest sweet in the UK?
There is no official measure, but Barnett's Mega Sours and Mr Simms Black Death are the two most often named, both British and both claiming the title of most sour sweet. Among the widely sold challenge brands, Toxic Waste and Warheads are the fiercest.
What makes sour sweets sour?
The sourness comes from food acids in the coating, mainly citric acid (the sourness in lemons) and malic acid, which is sharper and lasts longer. The more acid in the coating, the more intense the hit before it fades to a sweeter centre.
Are Toxic Waste and Warheads the sourest sweets?
They are among the most famous and certainly very sour, but some British boiled sweets like Barnett's Mega Sours are often claimed to be sharper still. Sourness is hard to measure, so it comes down to the acids used and personal tolerance.
Is there a scale for sourness like Scoville for spice?
There is no commercial scale. Scientists use a sourness index, but sweet makers do not, so there is no agreed number the way there is for chilli heat. Rankings rely on the acids used and on taste rather than a measured figure.
Do sour sweets get sweet after a while?
Most of them do. The intense sour coating dissolves after the first thirty seconds or so, and underneath is usually a sweeter sweet or gummy, which is why the strongest ones start fierce and finish sweet.
What is a good sour sweet for beginners?
Sour Patch Kids are the classic starting point, with a light tang before a soft, sweet centre. Sour gummy worms and milder sour chews are also easy to enjoy before working up towards the extreme end.
More Sour Sweets
- Browse the full sour sweets range.
- Take on the famous Toxic Waste drum.