According to the Penguin Companion to Food (2002), we Scots have a sweet tooth. Ever since the 15th century, when sugar started to be imported in significant volume, Scottish people have developed not just a love of confectionery but ‘an international reputation for the quality of their products’. In particular, toffee has a strong heritage in Scottish towns and cities: think tangy Moffat Toffee, creamy Helensburgh Toffee and golden syrup enriched Glasgow Toffee, not forgetting the iconic soft toffee bars by McCowan’s Highland Toffee, established in the 1920s.

What’s not fully appreciated by non-cooks is that sweet treats such as chewy toffee, unctuous caramel, yieldingly soft fudge and delectably toothsome tablet are all simply different versions of boiled sugar.

What gives each confection its own distinct characteristics are the temperature and stage it is boiled to as well as slight variations in recipe. Fudge and tablet, for instance, is the fondant result of sugar, butter and condensed or evaporated milk boiled to between 112º and 116ºC, or the ‘soft ball’ stage. Soft caramel, meanwhile, is the molten consequence of sugar enriched with butter, milk or cream and boiled to between 118º and 121ºC, or the ‘firm ball’ stage. And last but not least, toffee is the glossy product of sugar and butter boiled to between 121º and 130ºC, or the ‘hard ball’ stage.

The different stages are tested by dropping a little syrup into ice-cold water where it will form either a soft, firm or hard ball under the surface, which on contact with the air immediately disintegrates (soft ball), quickly loses its shape (firm ball), or maintains its shape and is quite malleable (hard ball).

That’s the science part!

The truth is that the secret to good caramel, toffee, tablet and fudge is experience. Sugar thermometers have been around since the late-19th century and are certainly an essential tool for the novice confectioner, but Carole Inglis of the Isle of Skye Fudge Company says there’s a skill in knowing when it’s ready.

‘I did use thermometers to begin with,’ Inglis explains, ‘but now I do it by timing and by eye.’

A classic cottage industry, the Isle of Skye Fudge Company started in Inglis’ kitchen in 2002. Using the same recipe handed down to her by her great grandmother who, at one time, owned a confectioner’s in Glasgow, now Inglis sells her traditional Scottish tablet in local shops and at tourist attractions as well as through her website. She also produces the hand-made confection for the Baxter’s Specially Selected Foods label.

So what exactly is the difference between fudge and tablet? ‘It’s to do with the texture,’ Inglis explains. ‘Tablet is smooth but slightly grainy and has a bite to it; with fudge you leave teeth marks when you bite into it – I’d say it has a more cloying texture than tablet.’

So why does Inglis call her company Skye Fudge rather than Skye Tablet? ‘People south of the border don’t know what tablet is!’

● You can find more about Scottish producers of tablet, fudge and other sweets at food.list.co.uk, including Isle of Skye Fudge Company, The Loch Leven Tablet Company, The Galloway Fudge Company, and Hebridean Toffee .