Pearl sugar, and where to get it here

The white lumps on top of a Swedish bun are pärlsocker, pearl sugar, and they are the detail that most obviously separates a real kanelbulle from an imitation. A bun finished with icing is a different food. A bun finished with caster sugar has nothing on it at all by the time it comes out of the oven.

Pearl sugar goes in and comes out. That is its entire job.

Why it survives, and why the usual explanation is wrong

You will be told that pearl sugar has a high melting point. It does not. It is sucrose, exactly the same molecule as the caster sugar in the cupboard, and it melts at the same temperature.

What is different is size and density. Pearl sugar is made by compressing and agglomerating sugar into hard opaque nibs, either by crushing and sifting blocks of it or by humidifying, pressing, drying, grinding and grading. The result is a particle far larger and denser than a sugar crystal.

Caster sugar does not vanish from a bun because it melts. It vanishes because it dissolves into the moisture on the surface of the dough and becomes part of it. A pearl is too big and too tightly packed to dissolve in the time a bun spends in an oven, and its interior never gets close to melting temperature.

Dissolution, not melting. It sounds like pedantry and it is actually the difference between an explanation that predicts behaviour and one that does not — which is why brushing a bun with too much egg wash or baking it slower and wetter will start to soften the pearls, and why a hotter, shorter bake keeps them crisp.

Nordic and Belgian are not the same grade

Both get sold as pearl sugar and they are different sizes for different jobs.

The Nordic grade is smaller and is a topping. It is what a kanelbulle or a kardemummabulle wants.

The Belgian grade is larger and is made for Liège waffles, where it is mixed into the batter and forms pockets of caramel inside. On top of a bun it looks oversized and tends to fall off.

If a supplier lists "pearl sugar" and nothing else, ask which.

Where to buy it in Australia

This is where the story was supposed to be about difficulty, and it is not.

It is not in the supermarkets. Coles and Woolworths sell decorative sugar pearls for cake decorating, which are a confectionery product and not a substitute. IKEA Australia does not stock it either, which is the more surprising absence, given that the Swedish Food Market carries the biscuits and the cordial.

But it is available. Scandinavian specialists here sell it online in 500-gram bags, including the actual Dansukker Swedish brand. At least one Melbourne-area wholesaler lists it by the kilo, close enough to drive to. And it comes in ten-kilo bags for anyone baking at volume.

So it is not scarce. It is simply not a supermarket item, which means it is a decision rather than something that ends up in the trolley. That is a different kind of obstacle and a much smaller one.

Using it

Press it on. Scattered loose it bounces off in the oven and burns on the tray.

Egg wash first, lightly. Too much and it dissolves the underside of the pearls and they slump.

Put it on before the final prove, not after. A proved bun is fragile, and pressing sugar into it at that point deflates the shape you spent time on.

And use less than looks right. Pearl sugar is a punctuation mark. A bun with an even white coating of it is a sugar biscuit with a bun underneath.