Sponge cake,a modern classic

The basic techniques in the kitchen are often centuries-old tried-and-tested methods. But sometimes, a new technique arrives on the scene. It took sous

vide more than 25 years to become a commonly used technique, for example, while the technique for using a siphon and microwave to make sponge cake

was developed less than ten years ago in the kitchen of ElBulli. Yet, this newly developed method has already become a classic preparation technique. This

comes as no surprise, as you can use this technique to create an extremely airy cake that can be used in both sweet and savoury dishes in no time and without

needing too much experience. In this whitepaper we’ll tell you everything you need to know about sponge cake.

Whitepaper contents Effortlessly airy

No sponge cake without a siphonVary with three tried-and-tested recipes yourself

Original sponge cake recipeSponge cake with a sweet or savoury liquidSponge cake with a vegetable or fruit puréeQuestions and answers about sponge cake

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Effortlessly airyTo create an airy cake in the classic patisserie-sense, air needs to be incorporated into the batter somewhere in the preparation method. This can be done in various ways:• By beating the fat with the sweetener until light and airy.• By beating the eggs with the sweetener until light and airy.• By beating all the ingredients together until light and airy (ready-made cake mixes).

The beating together of ingredients until light and airy, even with a planet mixer, takes time and the margin for error is small. With this modern preparation technique for sponge cake, the air is incorporated in no time by aerating the batter in the siphon with a charger. This is one of the reasons that this technique has become so incredibly popular, and this is helped by the fact that so many special flavours can be added. This is even the most-viewed component on Gastronomixs!

No sponge cake without a siphonThe siphon finds it origins in the technique that turns still water into a sparkling product. A few years later, this technique to create sparkling water was applied to whipped cream. In the early 1990s, Ferran Adrià gave a new dimension to the siphon by using it to develop the first espuma. This magical canister is now used in nearly every kitchen to quickly aerate liquids. Without siphons, we wouldn’t have the extremely airy sponge cakes we have come to know and love.

What happens inside the siphon?Instead of using air, the siphon is charged with a cartridge containing a neutral gas which pressurises the liquid in the siphon. This pressure combined with the shaking motion creates a foam that is stabilised by the proteins or fat in the liquid. The liquid is then squeezed from the siphon through a tiny opening. Once it has left the siphon, the pressure drops so rapidly that the gas expands, creating bubbles in the liquid. Shake the siphon well to evenly spread the gas throughout the liquid. This will ensure the best result. If you are using a thicker liquid, you might need to shake for a few minutes, but it’s still a breeze compared to beating by hand.

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Vary with three tried-and-tested recipes yourselfOnce you have a good basic recipe, you can freely vary on it. This is also the case for the popular sponge cake recipe on Gastronomixs. That’s why we took a closer look and developed three basic recipes during testing that you can use to push the boundaries even further. These basic recipes are not suitable for certain ingredients such as nuts, butter, and cheese.

Original Sweet or savoury liquid

Vegetable or fruitpurée

Lemon zest. Dried sea weed. Tea. Coffee. Cocoa. Freeze-

dried fruits or dairy. Ground spices such as vanilla of

cinnamon.

Syrups infused with herbs and spices. Bouillons such

as dashi, lobster bouillon or tomato bouillon. Liqueurs

such as limoncello.

Coulis or purée of red fruits, pear, exotic fruit, carrot, beetroot, spinach, potato, sweet potato or

mushrooms.

+ + +

Sponge cake

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Original sponge cake recipe

*Options for basic additions - Lemon zest - Cocoa - Tea - Coffee - Dried seaweed - Freeze-dried fruits such as pineapple, passion fruit, or raspberries - Freeze-dried dairy such as yoghurt - Ground spices such as vanilla, cardamom, sumac, tonka beans, star anise, liquorice, or cinnamon.

This is the original ElBulli recipe and consists of five ingredients, namely: egg white, ground almonds, sugar, flour, and egg yolk. Minor additions and variations can already create a completely different character. Always add the flavour enhancers in small amounts (max. 2%), so that they don’t become too predominant. In the table below we show how you can vary on this basic recipe.

Preparation method• Mix all the ingredients in a blender until smooth.• Sieve and then pour into a half-litre siphon.• Aerate with 2 whipping cream chargers (N2O)• Spray the mixture into a paper coffee cup in which a hole has been made in the bottom. Fill the cups no more than half-full.• Place in the microwave at full power for 40 seconds.• Allow to cool upside down.

Coffee sponge cake

Ingredients150 g egg white, pasteurised80 g ground almonds80 g sugar30 g flour60 g egg yolk2% basic addition*

Ferran en Albert Adrià are the founders of molecular gastronomy. These Catalan chefs were the driving force behind El Bulli*** restaurant, which was named the best restaurant in the world in 2006. They developed the sponge cake by endlessly experimenting with the ways in which they could apply science in the kitchen.

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Yuzu meringue

Chocolate mousse

Yuzu panna cottaCrispy chocolate

cookie

Salted hazelnut

Chocolate beignetYuzu gel

Chocolate sponge cake

On Gastronomixs.com you can find even more

compositions with sponge cake!

*Possible liquid variations:- Syrups infused with herbs or spices - Bouillons such as

dashi, lobster bouillon, or tomato bouillon - Liqueurs such as limoncello, Fraise des Bois, or mint - Tea - Vegetable juice.

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Sponge cake with a sweet or savoury liquidBy combining egg white powder with a liquid, you replace a part of the fresh egg whites. Add 10 grams of egg white powder to 100 ml of liquid and mix it well. This opens up a world of flavours and will also allow you to use sponge cake in hearty dishes.

Ingredients10 g egg white powder100 ml. liquid*150 g egg white, pasteurised80 g ground almonds80 g sugar30 g flour60 g egg yolk

Sponge cake is baked in the microwave. The advantage of this method is that heat is also applied to the centre of the product immediately. This rapid heating forces the gas in the batter to expand, giving it no chance to deflate. The large bubbles in the sponge cake are an indication of how quickly it has been baked.

Limoncello sponge cake

Preparation method• Mix all the ingredients in a blender until smooth.• Sieve and then pour into a half-litre siphon.• Aerate with 2 whipping cream chargers (N2O)• Spray the mixture into a paper coffee cup in which a hole has been made in the bottom. Fill the cups no more than half-full.• Place in the microwave at full power for 40 seconds.• Allow to cool upside down.

*Possible fruit coulis or vegetable purée variations- Coulis or purée of red fruits, pear, exotic fruit, carrot, spinach, beetroot, potato, sweet potato, or mushrooms.

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Sponge cake with a vegetable or fruit puréeIn this recipe, a vegetable or fruit purée serves as the flavour enhancer. Add spices and herbs to the purée for extra flavour. The purée or coulis makes the batter a little heavier creating a firmer end product.

Preparation method• Mix all the ingredients in a blender until smooth.• Sieve and then pour into a half-litre siphon. • Aerate with 2 whipping cream chargers (N2O)

Ingredients150 g fruit coulis or vegetable purée*160 g egg white, pasteurised40 g ground almonds30 g flour60 g egg yolk salt

A modern chef dares to experiment with flavours and searches to create the perfect balance in a dish. Starters might need a sweet element to accentuate the savoury characteristics of the dish. You can now easily add savoury flavours to your sponge cake, opening up a world of flavours. Did you know... that a sponge cake can also be dried in a food dehydrator? This results in a lightly crispy end product!

• Spray the mixture into a paper coffee cup in which a hole has been made in the bottom. Fill the cups no more than half-full.• Place in the microwave at full power for 50-60 seconds.• Allow to cool upside down.

Carrot sponge cake

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Can you freeze sponge cake?Yes, you can. Seal the sponge cake in a vacuum bag without pulling vacuum. But, in all honesty, this involves more work and is more expensive than baking a fresh sponge cake every day.

Why does sponge cake remain airy?Because the egg whites in the batter set in the microwave and solidify around the gas bubbles, thus trapping them in the process, the sponge cake remains airy. The setting of the egg whites is also called denaturation and this is what creates the solid structure.

What happens when the batter goes into the microwave?The radiation rapidly heats the batter, causing the gas in the batter to expand and create air bubbles. At 62°C the egg whites set and the batter becomes firm and the air is trapped inside the cake. If you leave the batter in the microwave for too long it will, of course, burn. For how long can you keep sponge cake?You can keep sponge cake in an air-tight container or sealed vacuum bag for about four days. But for the best result, we recommend that you bake it fresh daily.

What is the most commonly made mistake when making sponge cake?Not passing the batter through a sieve before

pouring it into the siphon. Bits and pieces left in the batter will block the nozzle of the siphon.

Can sponge cakes be used in main courses?Sponge cakes can be used in every course. For savoury sponge cakes you could use mushrooms, bouillons, or a vegetable purée as a basis.

Can I make a sponge cake without a siphon?Yes, but... this will always result in a less airy sponge cake. Use a planet mixer with wire whisk or a hand-held whisk to beat the batter until airy.

Why would I use sponge cake in a dish?It is a simple side dish that is bursting with flavour and that can elevate any dish to a higher level.

Can I make a sponge cake without flour? If you add enough egg whites to replace the gluten proteins, this should, in theory, be possible.

Can I add food colouring to a sponge cake?You can add powdered or liquid food colouring. Just remember that the colour that you pour into the siphon is not the colour that will emerge from the microwave.

Questions and answers about sponge cake

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