Sour Candy, Explained

Sour is one of the basic tastes, and in candy it nearly always comes from one thing: acid. Not the scary kind. The same food acids you'd find in a lemon, a green apple or a bunch of grapes.

Which acid a candy maker picks, how much they use and where they put it decides whether a candy is gently tangy or properly eye-watering.

• Citric acid is the sour in lemons and limes, and the one you'll see most often on a sour candy label. Most of it today is made by fermentation rather than squeezed from fruit.
• Malic acid is the tartness in green apples. Its name comes from malum, Latin for apple. It tastes sharper than citric acid, so extra-sour candy often uses it alongside citric or in its place.
• Tartaric acid is found in grapes and brings a drier, sharper edge.

Plenty of candies use a blend, so the sour hits fast and then hangs around a little.

That sparkly coat on a sour gummy is sugar mixed with powdered acid, tumbled over the candy after it's made. Because it sits on the surface, the sour lands first and the sweet centre follows.

Some candies put acid in the middle too, which is why a few bags stay sour all the way through.

Two bags can both say "sour" and taste nothing alike. It usually comes down to:

• How much acid is in the coat, and whether the centre is sour too.
• Which acids are in the blend.
• How much sugar sits next to the acid. More sweet softens the bite.
• Shape. Thin strips and small pieces carry more coated surface for their size than a chunky gummy does.

The ingredient list names the acids in order, from the most to the least, so it tells you a fair bit before you open the bag.

Sour candy isn't one style. Some lean fruity, with just enough acid to wake the flavour up. Some are built for maximum pucker. And candy from Mexico often pairs sour with lime, tamarind or chili, a mix you can try in the spicy Jarritos gummies that sit right next to the sour ones.

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