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Best caterpillar cakes: Colin vs supermarket rivals
M&S has been selling its popular Colin Caterpillar for more than 30 years, but these days the iconic British birthday cake faces increased competition.
From Slinky to Cecil, plenty of other supermarkets now get a slice of the action.
Colin is the priciest of the bunch at £9.50, while Aldi's Cuthbert is just £5.49, offering a decent saving if you're after a cheaper way to feed the party. So is it worth paying more?
To find out which caterpillar cake reigns supreme, we asked a panel of 75 consumers to rate eight caterpillar cakes in a blind taste test.
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Best caterpillar cakes
While the overall design varies, all the caterpillar cakes consist of a rolled chocolate sponge filled with chocolate-flavoured buttercream, all covered in a solid chocolate shell.
In our taste test, Colin held his ground as an established favourite and earned a Best Buy, but he was pipped to the post by Co-op's cheaper 'Charlie' caterpillar cake, which came top overall.
If you can't get to a Co-op, finding a crowd-pleasing caterpillar cake shouldn't be too much of a challenge as most supermarkets scored reasonably well.
However, our two Best Buys were rated a cut above the rest for texture, so if a dry sponge is a dealbreaker for you then it's worth seeking them out.
Best Buy: Co-op 'Charlie the Caterpillar' cake – 72%
£8 for 660g (£1.21 per 100g), serves 12
The Co-op might not have been your first port of call for a caterpillar cake, but it's our top-rated option.
Charlie just edged ahead of M&S's Colin Caterpillar to become our highest-scoring caterpillar cake overall.
Achieving the ultimate combination of rich chocolate flavour, moist sponge and soft buttercream is no easy feat, but Charlie outshone other supermarket rivals, earning top marks across the board.
There's no skimping on the buttercream either. Co-op's caterpillar is the only one that really nails the perfect balance of sponge and buttercream, and more than three quarters of the panel found the ratio spot on.
And if that's not enough to convince you, it's also cheaper (and bigger) than Colin, so you can save some cash – and make it go further – while savouring its superb flavour.
Available from Co-op (in-store only).
Best Buy: M&S 'Colin The Caterpillar' cake – 71%
£9.50 for 625g (£1.52 per 100g), serves 10
M&S proved that its Colin the Caterpillar cake is a classic for a reason. It won over our tasters with its super sponge and delicious chocolatey flavour.
While it just missed out on the top spot, it's still one of the best-tasting supermarket caterpillar cakes around, beating rivals from the likes of Sainsbury's, Waitrose and Aldi.
At £9.50, Colin is the most expensive caterpillar cake we tested per 100g. The version we tested serves 10, but if you're feeding a crowd of Colin fans, you may want to get your hands on M&S's Giant Colin the Caterpillar Cake, which serves 40 people and costs £50. You can also get it personalised with a message of your choice.
If you're considering branching out from Colin, M&S also sells Connie the Caterpillar, who is decorated with sugar hearts and pink chocolate feet. Mini Colins and Connies are also available (£3.50 for 5, from Ocado or M&S in-store).
Available from Ocado and M&S (in-store only).
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How the other caterpillar cakes scored
Our taste test suggests you can't go too far wrong with a caterpillar cake, though Asda's got the lowest score overall. A dry sponge was the main problem common to lower scorers.
Aldi's cake is the best value if price is key. Here's how the rest stack up:
Morrisons 'Morris the Caterpillar' cake – 70%
£7.50 for 624g (£1.20 per 100g), serves 12
Morris wasn't quite as impressive as our Best Buys, but it managed a respectable third place overall, tying with Sainsbury's.
Our tasters enjoyed its flavour and 71% found the sweetness just right.
Most tasters liked the texture of the buttercream but the sponge was a little disappointing, with just over half finding it too dry.
Available from Morrisons.
Sainsbury's 'Wiggles the Caterpillar' cake – 70%
£7.50 for 627g (£1.20 per 100g), serves 14
Wiggles is one of the most similar looking caterpillars to Colin, so if you're keen for a lookalike it's a good bet.
It was rated highly for its chocolatey flavour, but some found the sponge was lacking moistness and nearly a third thought the chocolate shell was too thin.
While Sainsburys says its Wiggles cake serves 14 people, the overall size is similar to other caterpillar cakes we tested, which typically feed 12 people. Following the recommended amount will give you smaller-than-average slices.
Available from Sainsbury's.
Waitrose Cecil the Caterpillar Cake – 69%
£8.50 for 720g (£1.18 per 100g), serves 12
Weighing in at 720g, Cecil is the biggest caterpillar cake we tested, so although it's more expensive than most overall, it's actually one of the cheaper cakes by weight.
It's a decent choice. Most tasters were satisfied with the strength of chocolate flavour, the sweetness and the thickness of the chocolate shell.
Some felt the amount of buttercream was stingy, with 45% finding the ratio of sponge to buttercream a bit off.
Cecil also contains the most sugar of all the caterpillar cakes we tested, packing in 47.2g of sugar per 100g.
Available from Waitrose.
Aldi 'Cuthbert the Caterpillar' cake – 68%
£5.49 for 625g (88p per 100g), serves 12
Colin and Cuthbert have faced their fair share of controversy in recent years, after M&S launched legal action against Aldi in 2021 for trademark infringement.
According to our consumer panel, Colin can rest easy: Cuthbert is no match for the original. While this cake scored well on flavour, nearly half of tasters found the texture of the sponge too dry.
It's the cheapest by far though – a significant saving compared to M&S. If you're after a budget birthday cake, it's not a bad choice.
Available from Aldi.
Tesco 'Slinky the Caterpillar' cake – 68%
£7.50 for 648g (£1.16 per 100g), serves 12
Tesco is one of a handful of supermarkets to ditch the classic white chocolate face in favour of a more colourful option. 'Slinky' has a cheery bright orange visage.
The overall flavour of this cake was well rated but the texture of the sponge let it down; nearly half of our tasters found it too dry. A third also felt it lacked enough buttercream.
It has the least sugar per 100g of the caterpillar cakes we tested, although it still falls in the 'red traffic light' zone as it contains more than 22.5g sugar per 100g.
Like M&S, Tesco also sells a pink caterpillar version, named Fuzzy the Caterpillar cake.
Available from Tesco.
Asda 'Letty the Caterpillar' cake – 67%
£7.50 for 615g (£1.22 per 100g), serves 12
Asda's Letty, with her lurid green face, came in last overall in our taste test.
While this cake didn't score too poorly overall, there are tastier and cheaper options elsewhere.
More than a third of tasters thought the chocolate flavour was too weak, while 63% found the sponge too dry.
Letty is also the smallest of the supermarket caterpillar cakes, so the serving size per person is less generous compared with most others we tested.
Available from Asda.
Looking for more party food favourites? Check out our pick of the best vanilla ice cream
Vegan and Free From caterpillar cakes
None of the caterpillar cakes we tested are suitable for vegans. If you're after a dairy-free or gluten-free version, several supermarkets offer 'free from' and vegan options. These include:
- Sainsbury's Free From 'Eric the Caterpillar' cake, £7 for 592g. Available from Sainsbury's
- Asda Free From 'Frieda the Caterpillar' cake, £7 for 488g. Available from Asda
- Morrisons Free From 'Freddie the Caterpillar' cake, £7 for 610g. Available from Morrisons
- Tesco Free From 'Stripey the Caterpillar' cake, £7.50 for 600g. Available from Tesco
- Lazyday 'Mini Vic the Vegan' caterpillar cakes, £3.50 for 200g. Available from Morrisons and Sainsbury's
Fancy baking your own cake instead? See our reviews of the best stand mixers, the best cake tins and the best kitchen scales.
Do caterpillar cakes contain palm oil?
All of the caterpillar cakes we tested contain palm oil. The supermarkets included in our taste test state that they only use responsibly sourced palm oil. Most use RSPO certified palm oil, which means the oil has been accredited as sustainably produced under the RSPO scheme.
How we tested caterpillar cakes
The caterpillar cakes were taste-tested in February 2024 by a large panel of consumers who like to eat this type of celebration cake. The panel broadly represents the demographic profile of adults in the UK.
Each caterpillar cake was assessed by 75 people. Tasters rated the taste, texture, aroma and appearance of each product, and told us what they liked and disliked about each one.
The taste test was blind, so people didn’t know which brand they were trying. The order in which they sampled the caterpillar cakes was rotated to avoid any bias and each person was in a private booth so they couldn’t discuss what they were tasting or be influenced by others.
The overall score is based on:
- 50% flavour
- 30% appearance
- 10% aroma
- 10% texture
Tasters rated the overall visual appeal of the cakes separately to tasting a slice.
How to recycle caterpillar cake packaging
The outer box and cake board can usually be put in regular household recycling, unless stated otherwise.
However, the clear plastic window is not recyclable and needs to be removed before you put it in your recycling bin.
Prices and availability information last checked 3 July 2024.