Temperatures for sugar, chocolate and deep-frying
In baking and desserts, it is often just a few degrees that separate success from failure. A thermometer with a long probe, preferably digital, saves both ingredients and patience.
Sugar syrup · Chocolate · Deep-frying · Custard and ice cream bases · Yeast and gelatine
Sugar syrup
When sugar is boiled with water, the water evaporates and the temperature rises. The hotter the syrup gets, the harder the sugar sets when it cools. The stages have old names after how a drop behaves in cold water.
| Stage | Temperature | Used for |
|---|---|---|
| Thread | 106–112 °C225–235 °F | Icing and syrups |
| Soft ball | 112–116 °C235–245 °F | Fudge and soft caramels |
| Firm ball | 118–120 °C245–250 °F | Italian meringue and caramels |
| Hard ball | 121–130 °C250–270 °F | Nougat and marshmallows |
| Hard crack | 149–154 °C305–310 °F | Toffee and lollipops |
| Caramel | 160–175 °C320–350 °F | Caramel and nougatine |
For Italian meringue, a sugar syrup at 118 °C245 °F is whisked into the egg whites. It makes the meringue so stable that it doesn’t need baking.
Don’t stir the syrup once the sugar has dissolved, or it may crystallise and turn grainy. Brush sugar crystals down from the sides of the pan with a wet pastry brush.
Chocolate
Melted chocolate needs to be tempered if it is to set glossy and snap when you break it, for example for chocolate shells or dipped berries. That means melting it completely, cooling it down and warming it again to an exact working temperature.
| Chocolate | Melt to | Cool to | Work at |
|---|---|---|---|
| Dark | 45–50 °C113–122 °F | 27–28 °C81–82 °F | 31–32 °C88–90 °F |
| Milk | 40–45 °C104–113 °F | 26–27 °C79–81 °F | 29–30 °C84–86 °F |
| White | 40–45 °C104–113 °F | 25–26 °C77–79 °F | 28–29 °C82–84 °F |
The easiest way to cool it down is to stir in finely chopped chocolate, about a third of the total, until it has melted. If the chocolate is only going into a mousse or a cake, it doesn’t need tempering. Just melt it gently, ideally over a bain-marie, and never let white chocolate get hotter than 45 °C113 °F.
Deep-frying
The oil should stay at 170–180 °C340–360 °F for most things: fish, vegetables and anything breaded.
Chips (fries) are fried twice. First at 140–150 °C285–305 °F until soft but without colour, then at 180 °C360 °F until golden and crisp.
Fry in small batches so that the oil doesn’t cool down, and wait until it is back at the right temperature before the next batch.
Custard and ice cream bases
Crème anglaise, the base for custard and most ice creams, thickens when the egg yolks start to set at around 80 °C176 °F. Take it off the heat by 85 °C185 °F at the latest, or it turns grainy with tiny lumps of set yolk. It is ready when it coats the back of a spoon and a line drawn with your finger stays put.
Yeast and gelatine
Fresh yeast likes a dough liquid at 37 °C99 °F, lukewarm to the touch. Dried yeast can be mixed into the flour and takes liquid at 40–45 °C104–113 °F. Above 55 °C131 °F, the yeast dies.
Gelatine dissolves in warm liquid at around 50–60 °C122–140 °F, but should not boil, or it loses some of its setting power.