Ganache
Ganache is a smooth mixture of chocolate and hot cream. It is an emulsion: tiny droplets of fat suspended in a water-based liquid. Changing the ratio of chocolate to cream turns it into anything from a pourable sauce to a firm truffle centre.
The science
Chocolate is mostly cocoa solids, sugar, and cocoa butter. Cream is mostly water with about 35% milk fat. When hot cream meets chopped chocolate, it melts the cocoa butter and dissolves the sugar. Stirring breaks the fats into small droplets dispersed through the cream's water, with cocoa particles and sugar thickening the water phase.
Lecithin in chocolate and proteins in cream act as emulsifiers, coating the fat droplets and stopping them from merging. As it cools, the cocoa butter partially solidifies, which is why ganache thickens and sets.
Ratios
All by weight, chocolate to cream (35% fat):
| Use | Dark (55–70%) | Milk | White |
|---|---|---|---|
| Sauce, whipped ganache | 1:2 | 1:1 | 1.5:1 |
| Glaze, drip, soft frosting | 1:1 | 2:1 | 2.5:1 |
| Firm frosting, tart filling | 1.5:1 | 2.5:1 | 3:1 |
| Truffles, rolled centres | 2:1 | 3:1 | 3.5:1 |
Milk and white chocolates have less cocoa solids and more milk fat and sugar, so they set softer and need more chocolate for the same structure.
How to make it
- Chop the chocolate finely and evenly so it melts at the same rate. Put it in a heatproof bowl.
- Heat the cream until it just steams and small bubbles form at the edge, about 80–90 °C / 175–195 °F. Do not let it boil hard.
- Pour the cream over the chocolate and leave it for 1–2 minutes.
- Stir from the centre in small circles, gradually widening. You will see it turn glossy as the emulsion forms.
- If bits remain, warm briefly over a pan of hot water or in 10-second microwave bursts.
For an ultra-smooth result, finish with an immersion blender held under the surface to avoid air bubbles.
Fixing broken ganache
A split ganache looks oily, grainy, or curdled. Causes:
- Too hot: cream boiling hard or chocolate overheated.
- Too little water: high-cocoa chocolates (over 70%) need more cream.
- Too cold: cream added cold, or set too fast.
Fix it by adding 1–2 tbsp warm milk or cream and stirring vigorously from the centre, or blending. The extra water gives the fat droplets room to disperse again.
Variations
- Flavoured: infuse the cream with tea, coffee, citrus zest, or spices, then strain and reheat.
- Whipped: chill a 1:2 ganache for several hours, then whip it like cream until fluffy.
- Glossy and soft: replace about 10% of the cream with glucose, corn syrup, or invert sugar for shine and a smoother set.
- Butter finish: stir in a little soft butter at about 35 °C / 95 °F for a silkier texture.
Questions
What is the ratio of chocolate to cream for ganache?
For dark chocolate (55–70%), use 1:1 by weight for glaze, drips, and frosting, 2:1 chocolate to cream for truffles, and 1:2 for a pourable sauce or whipped ganache. Milk and white chocolate need more chocolate for the same firmness.
Why did my ganache split or look greasy?
The emulsion broke, usually because the cream was too hot, the mixture was overheated, or there was too little liquid for the amount of cocoa butter. Whisk in 1–2 tbsp warm milk or cream, or blend briefly with an immersion blender, to bring it back together.
How long does ganache take to set?
A 1:1 dark ganache thickens to spreadable at room temperature in about 1–2 hours, or 20–30 minutes in the fridge with occasional stirring. A 2:1 truffle ganache needs 2–4 hours to firm enough to scoop.
Does ganache need to be refrigerated?
A firm ganache with plenty of chocolate keeps about 2 days at cool room temperature. For longer, refrigerate it for up to 2 weeks and bring it back to room temperature before using.