Ptasie mleczko: a foam built on hot syrup, not raw whites
Homemade ptasie mleczko is usually built on raw egg whites, and that is its great weakness: the foam can be unstable, and raw egg always carries some risk. The version using hot sugar syrup solves both at once — syrup poured into whipping whites at 120 °C cooks them as it goes, giving a foam that is dense, stable and far safer than one whipped from raw whites. It is the Italian meringue technique.
Your own work in that: 2 h.
- The foam 35 min
- Setting 180 min
- Chocolate top 85 min
Step by step
0 / 6 doneSoak the gelatine
Cover the gelatine with cold water and leave 15 minutes to swell. Then dissolve it in a water bath until clear and keep it warm — gelatine that has set again will leave hard lumps in the foam.
Ingredients: 4 pcs egg whites · 250 g sugar · 80 ml water · 25 g gelatine · 120 ml cold water · 1 tbsp lemon juice · 2 tbsp vanilla sugar · 100 g butter · 1 pinch salt
Boil the syrup to 120 degrees
Cover the sugar with water and boil without stirring until a thermometer reads 120 °C (about 8 minutes). Without a thermometer: a drop of syrup in cold water should form a firm but pliable ball you can shape between your fingers.
TipDon't stir the syrup with a spoon. Movement crystallises sugar on the sides and the syrup turns grainy. If crystals appear, wash them down with a wet pastry brush.
One hundred and twenty degrees, a firm, pliable ballPour the syrup into whipping whites
When the syrup reaches 110 °C, start whipping the whites with the salt to stiff peaks. At 120 °C pour the syrup in a thin stream down the side of the bowl, not onto the whisk, and keep whipping 8–10 minutes, until the bowl cools to lukewarm. The foam turns dense, white and glossy.
Ingredients: 4 pcs egg whites · 250 g sugar · 80 ml water · 25 g gelatine · 120 ml cold water · 1 tbsp lemon juice · 2 tbsp vanilla sugar · 100 g butter · 1 pinch salt
TipSyrup poured onto a moving whisk splatters up the sides and sets into hard threads that end up in the foam. So pour it down the side of the bowl.
A thin stream down the side, not onto the whiskBeat in gelatine and butter
Pour the warm gelatine into the lukewarm foam in a thin stream, whipping at medium speed. Then add the soft butter a spoon at a time, beating after each. Finish with the lemon juice and vanilla sugar. The mixture should be thick and glossy, like a buttercream.
TipThe butter must be at room temperature. Cold, it sets into small lumps in the foam that stay noticeable in the finished dessert.
Gelatine first, then butter spoon by spoonSpread in the tin and chill
Line a 22 × 30 cm tin with paper, spread the foam in it and level it quickly — the mixture begins to set within minutes. Refrigerate at least 3 hours, until completely firm and springy to the touch.
Level it fast; it sets within minutesCoat with chocolate and cut
Melt the chocolate with the cream and butter, cool to lukewarm and pour it over the foam, spreading it in a thin layer. Chill 60 minutes. Cut with a knife dipped in hot water, in one decisive stroke — sawing shatters the chocolate.
Ingredients: 200 g dark chocolate, 60 % · 80 ml cream, 30 % · 20 g butter
A thin layer, a knife dipped in hot water
Before you start
Without a thermometer
The cold water test is accurate enough: a drop of syrup in a glass of cold water should form a soft ball. A hard, brittle ball means the syrup went past about 130 °C — it will leave hard sugar threads in the foam, so it is better to start the syrup again.
With a sponge base
A popular homemade version of the ptasie mleczko cake has a thin sponge layer underneath. In the same tin, bake a sponge of 2 eggs, 60 g sugar and 60 g flour (about 12 minutes at 180°C), cool it and pour the foam on top — the dessert is then far easier to cut and move.
Flavours
Instead of vanilla: 2 tablespoons of lemon juice and zest for a lemon version, or 3 tablespoons of raspberry purée. Don't add more liquid than that or the foam will not set.
How long it keeps
Up to a week in a sealed container in the fridge — a foam cooked by hot syrup keeps better than one built on raw whites. Don't freeze it: after thawing the foam weeps and the chocolate turns dull.
