Hard-crack stage
The hard-crack stage is sugar syrup cooked to 149 to 154°C (300 to 310°F). A drop in cold water forms brittle threads that snap. It makes brittle.
Also called Hard crack.
The hard-crack stage is the hottest of the standard sugar stages before caramel, reached at 149 to 154°C (300 to 310°F) at sea level. A drop of syrup in cold water turns into hard, brittle threads that break cleanly. The syrup now has almost no water left and sets like glass. Lollipops, hard candy, peanut brittle, butterscotch, toffee apples and spun sugar are made at this stage. It comes after the soft-crack stage.
How to do it
- Use a heavy, clean saucepan and a candy thermometer.
- Dissolve the sugar in water over medium heat, stirring, before it boils. Many recipes add corn syrup or glucose to help stop crystals forming.
- Stop stirring once it boils. Brush down the sides with a wet pastry brush.
- Boil until it reaches 149 to 154°C (300 to 310°F). It will be thick, with slow, large bubbles, and may start to turn pale gold.
- Take it off the heat at once. Add flavorings, nuts or color as the recipe says. Stand back: they may spit.
- Pour or shape straight away. It sets within minutes.
How to tell it is done
Drip a little syrup into very cold water. At hard crack, it hardens at once into threads or a lump that snap with a clean crack when you bend them and do not stick to your teeth. If they bend or feel chewy, it is still at soft crack.
Why it works
At this temperature the syrup is about 99 percent sugar. With so little water, the sugar molecules lock into a glassy solid as they cool instead of forming a soft paste. Just above this range, at about 160°C (320°F), the sugar starts to caramelize and turn brown.
Common mistakes
- Pulling it too early. The candy stays tacky and bends instead of snapping.
- Going too far. Past 160°C (320°F), the color and flavor change to caramel and then burn quickly.
- Touching the syrup. Sugar at this stage causes serious burns and sticks to skin. If you get some on your skin, cool it under cold running water. Keep children away.
- Storing in a humid place. Hard candy absorbs moisture and goes sticky. Keep it airtight.
In recipes
"Cook to the hard-crack stage" and "cook to 150°C (300°F)" both mean this. The caramel top of a brûlée sets to the same glassy texture.
Related terms
- Soft-crack stageThe soft-crack stage is sugar syrup cooked to 132 to 143°C (270 to 290°F). A drop in cold water forms threads that bend before they break. It makes taffy.
- CaramelizationCaramelization is the browning of sugar under heat, which turns it from plain sweet to rich, nutty and a little bitter. It is not the Maillard reaction.
- BrûléeBrûlée means burnt in French. To brûlée is to melt sugar on top of a dessert with a torch or broiler until it sets into a thin, glassy caramel shell.
- ThermometerA kitchen thermometer checks the heat of meat, oil, sugar and your oven, so food is safe and cooked how you want. Here is which type to use and how.
- Hard-ball stageThe hard-ball stage is sugar syrup cooked to 121 to 130°C (250 to 266°F). A drop in cold water forms a hard, sticky ball. It is used for nougat.