Water Ganache

A chocolatier’s worse nightmare.

Watering down my chocolate goes against everything I’ve been taught.  Should a few drops of water land in my chocolate, disaster! My chocolate is no longer fit for duty. As it turns out, mixing water into chocolate isn’t necessarily a bad thing.

During the 1990s, Herve This and Heston Blumenthal noted that dairy and eggs mute the flavor of chocolate and developed an eggless, dairy-free chocolate mousse. Chocolatiers elaborated on this technique to create ganache-centered bonbons that blend their chocolate fillings with water instead of cream. Although this technique was not developed for dietary reasons, water-based ganache is commonly referred to as vegan chocolate and has become the signature technique of renowned pastry chef Damian Allsop and chocolatier Aneesh Popat.

In the pastry kitchen, ganache is reputed as a finicky blend of chocolate and liquid (link). It is as simple as it is complex and every detail matters: the choice of chocolate, the proportion of liquid to chocolate, and how the liquid and chocolate are blended. One detail often overlooked but no less important is the type of liquid used.

Chocolatiers traditionally blend ganache using cream whose main components of butterfat and water are homogenized to create an emulsion, a suspension of two liquids that don’t want to be mixed. When these liquids are forced into an emulsion, one liquid forms a dispersed phase that is contained within the other liquid, the continuous phase. Oil-in-water emulsions, like mayonnaise, exist when fat is dispersed into water. They are more common in the kitchen than water-in-oil emulsions, such as butter, where water is dispersed into fat. Ganache itself is an emulsion, and in water-based ganache, enough water is mixed into chocolate to disperse the cocoa butter and create an oil-in-water emulsion, a form made possible by chocolate’s unique composition.

In its solid form, chocolate is a stable dispersion of cocoa solids, cocoa butter, and sugar. The sugar is hydrophilic and attracted to water while the cocoa butter is hydrophobic and repels water[1]. Lecithin, an emulsifier, is added to chocolate to surround the sugar with a protective layer that prevents it from separating from the cocoa butter. When chocolate is melted, its stability is easily disrupted by free water molecules, such as the water droplets on a damp spatula. When this miniscule amount of water bonds with the water-loving sugar, the sugar and cocoa solids clump and separate from the cocoa butter[2] causing the chocolate to become every chocolatier’s nightmare: clumps of grainy chocolate spotted with oily slicks of cocoa butter. Because most chocolates contain prodigious amounts of sugar, it doesn’t take much water to seize a bowl of chocolate and make it grainy.

Continuing to add water will disperse the fat and invert a W/O emulsion into an O/W emulsion (e.g. water-based ganache)

A schematic diagram of too little and too much water in chocolate

Stirring more water into seized chocolate smoothes its texture by inverting the water/oil emulsion into an oil/water emulsion. At 20% by weight (of the chocolate), the water becomes the continuous phase that disperses the fat (cocoa butter) and solids (sugar and cocoa). This dispels the popular notion that the cream provides the ‘creamy’ texture of ganache. It is the water. There is one caveat to this technique though. Water ganache magnifies the slightest imbalance of astringency or bitterness in a mediocre chocolate. In other words, crap chocolate will taste crappier when only water is added.

Beyond plain water, any flavored liquid can be used: fruit purees, tea, beer, coffee, nut/grain/cereal milks, wine or water steeped with fresh herbs or spices. Some flavors, like citrus zest and spices, are fat soluble and release their flavor more readily in cream. As a workaround, infuse these flavors into a neutral fat, like grapeseed oil or cocoa butter, and blend into the chocolate before it is emulsified with a liquid.

BASIC RECIPE

500 g chocolate, 70% melted to 90 degrees F

200-300 g mineral water, room temperature

Stir water into chocolate a little at a time. The ganache will initially thicken, separate and re-emulsify with the last addition of water. The lower amount of water will produce a ganache that is firm enough to pipe into truffle centers. The higher amount of water will produce a soft textured ganache for bonbon fillings.

Chocolate not only determines the flavor of the ganache but the rigidity of its final texture. Changing the ratio of water to chocolate or using couverture chocolates with low cocoa butter and high sugar contents yields ganache of varying textures. 500g of water and 750g of chocolate produces a ganache like softened butter while 500g of water and 1500g of chocolate produces a firm ganache that can be molded and cut into pieces.

VARIATIONS:

Dark Chocolate (non-vegan): 250g 72% dark chocolate, 210g water, 50g dry butter, 30g trimoline, 2g salt (by Cacao Barry)

Dark Chocolate-Coconut: 450g 64% dark chocolate, 525g coconut milk, 25g coconut oil (by Chef Ji Yoon)

Pear: 350g Opalys white chocolate, 200g pear puree (reduced by half), 55g invert sugar, 25g pear eau de vie

Berry-Wine: 800g 64% dark chocolate, 300 g berry puree, 50g port (or sweet red wine), 80g trimoline, 5 g salt

When the cream is omitted, the fat content of the ganache formula must be balanced with another fat to achieve the optimal 40% fat content. Three quarters of the fat in a water ganache recipe should come from cocoa butter as it has the most pleasant aroma, flavor, and melting point. The remaining quarter can come from a soft fat such as coconut. The butterfat in heavy cream can also be replaced with a 50-50 ratio of cocoa butter to oil, be it olive oil, infused oils or nut oils.

Putting these guidelines into practical terms, one can substitute 1000 grams of 37% heavy cream to create a soft, creamy vegan coconut chai truffle by adding 370g of fat (185g cocoa butter and 185g coconut oil) and 630g of liquid (chai tea and coconut milk). The finished truffle recipe therefore is:

1200g 64% dark chocolate

185g cocoa butter

185g coconut oil

420 g strong black chai tea

210 g coconut milk

80 g glucose

where 185g of cocoa butter + 185g coconut oil + 420g chai tea + 210g coconut milk would equal 1000 grams of 37% heavy cream in the traditional recipe.

As others have rightly observed, the shelf life of water ganache is woefully short as the increased water content increases the odds of spoilage. But when chocolate tastes this good, why wait to eat it?

Special gratitude to Erik Fooladi (schematic illustration of seized chocolate) and Jean-Pierre Wybauw .

[1] Scientists are unsure whether cocoa solids are hydrophilic or hydrophobic although evidence leans toward cocoa solids tending to repel water.

[2] Increasing the emulsifier in chocolate also increases the viscosity of the chocolate. Increased viscosity makes it difficult to mold chocolate into thin, delicate shapes so manufacturers use just enough emulsifier to keep the chocolate shelf stable. However such small amounts of emulsifier are not sufficient to prevent the chocolate from seizing when small amounts of water are mixed into the chocolate.