Chocolate Truffles: The Ganache Ratio That Rolls

Published 14 Oct 20267 min read

A chocolate truffle is the simplest confection in the chocolate shop and the one most often gotten wrong at home. It is ganache, chocolate melted into hot cream, made firm enough to hold a shape, rolled into a rough ball and dusted with cocoa so it resembles the knobbly underground fungus that shares its name. Two ingredients, no candy thermometer. Everything depends on one number: how much cream goes in for how much chocolate.

What ganache is

Ganache is an emulsion, two things that do not normally mix held together in one smooth mass. Cream brings water, with milk fat dispersed through it. Chocolate brings cocoa butter, cocoa solids and sugar. Stirred together warm, they form the glossy, spoonable cream that sets as it cools.

A study in the Journal of Food Science, summarized by the Institute of Food Technologists, looked at ganache as a system and found what every chocolatier learns by hand. Sugar and milk powder dissolve in the watery cream and make a softer ganache; more defatted cocoa solids make it harder, less spreadable and more resistant to deformation. The study also found that the milk fat globules from the cream rupture during mixing and blend with the cocoa butter. In plain terms: the more cocoa solids in the chocolate, the firmer the ganache, and the more cream it can take.

The ratio, by chocolate

That explains why dark, milk and white chocolate need different amounts of cream. U.S. standards of identity set the minimums. Semisweet and bittersweet chocolate must contain at least 35 percent chocolate liquor, the ground cacao that carries the cocoa solids. Milk chocolate needs at least 10 percent chocolate liquor and 12 percent milk solids. White chocolate contains no chocolate liquor at all; the rule is at least 20 percent cacao fat and 14 percent milk solids, with up to 55 percent sweetener.

Chocolate	Chocolate to cream, by weight	For 250 g chocolate	Why
Dark, 64 to 72 percent	2 to 1	125 g cream	Plenty of cocoa solids to firm the set
Dark milk, 50 to 55 percent	2.5 to 1	100 g cream	Fewer cocoa solids, more milk and sugar
Milk, 30 to 40 percent	3 to 1	85 g cream	Mostly sugar and milk solids; sets soft
White	3 to 1, plus a firm chill	85 g cream	No cocoa solids at all; firms on cocoa butter alone

These are rolling ratios, firmer than a ganache for glazing a cake, which takes about equal weights of dark chocolate and cream. The percentage on the wrapper is the guide: the higher it is, the more cream the chocolate can carry. The guide to what the percentage on a chocolate bar means explains the number.

The chocolate to use

Use chocolate you would eat on its own, since the truffle tastes of little else. Valrhona's Guanaja 70 percent feves, small discs made for melting, need no chopping and melt evenly; Valrhona describes Guanaja as intensely bitter with warm and floral notes (shop Valrhona Guanaja 70% feves). One 250 g bag is exactly one batch of this recipe. For milk chocolate truffles at the 2.5 to 1 ratio, four or five bars of Dick Taylor's 55 percent vanilla milk, made with Ugandan cacao, whole milk and Madagascan vanilla, give a caramel-toned truffle (shop Dick Taylor vanilla milk 55%). The chocolate bars collection has more by percentage.

Ingredients

Makes about 24 truffles.

250 g dark chocolate, 64 to 72 percent, in feves or finely chopped
125 g (125 ml) heavy cream
15 g soft unsalted butter, optional, for a silkier center
Pinch of fine salt
About 30 g cocoa powder for coating, or finely chopped nuts (shop Valrhona cocoa powder)

Method

Prepare the chocolate. Put the chocolate in a heatproof bowl. If using a bar, chop it finely; small, even pieces melt before the cream cools.
Heat the cream. Heat the cream with the salt in a small pan until it just reaches a simmer, with small bubbles around the edge. It does not need to boil hard.
Make the emulsion. Pour the hot cream over the chocolate and leave it alone for 1 minute so the heat moves into the chocolate. Then stir from the center outward in small circles with a spatula. At first it looks thin and streaky; keep stirring and a glossy, thick center forms and spreads outward until the whole bowl is smooth. Stir in the butter once the ganache is warm rather than hot.
Let it set. Cover and leave at room temperature for 1 hour, then refrigerate for about 2 hours, until firm enough to scoop and hold its shape, like cold peanut butter.
Scoop and roll. Scoop 15 g portions, a heaped teaspoon each, onto a tray lined with parchment. Rinse your hands under cold water and dry them, then roll each portion quickly between your palms into a rough ball. Warm hands melt the outside; work fast, and rinse again halfway through. Chill the balls for 15 minutes.
Coat. Roll the balls in cocoa powder or chopped nuts, shaking off the excess. Irregular is correct; a truffle is meant to look like one.
Store and serve. Keep them in a closed container in the refrigerator, and take them out about 30 minutes before serving so the centers soften and the flavor opens.

When the ganache splits

A split ganache looks greasy or grainy, with a slick of fat on the surface. Usually it got too hot, or the balance tipped toward fat with too little liquid to hold it. It can almost always be saved. Warm a tablespoon of cream or milk, add it to the ganache, and stir hard from the center, or use an immersion blender held below the surface so it does not whip in air. The extra liquid gives the fat something to emulsify into again, and the gloss comes back.

A ganache that will not set has too much cream for its chocolate. Melt in more chocolate, 25 g at a time, and chill again. One that is too hard to scoop can sit at room temperature for half an hour.

Altitude

Denver cooks can follow this recipe as written. Colorado State University Extension gives the boiling point of water as 203 F at 5,000 feet, and the cream needs to reach no more than a simmer, so the lower boiling point makes no practical difference. Nothing here depends on a candy temperature.

Coatings and finishes

Cocoa powder. The classic, bitter against the sweet center.
Chopped nuts. Toasted hazelnuts, pistachios or almonds, chopped fine.
Flaky salt. A few flakes pressed on top of a cocoa-dusted truffle.
A chocolate shell. Dipping in tempered chocolate gives a snap and a longer life outside the fridge, but tempering is its own technique; the guide to why chocolate turns white explains what happens when the cocoa butter is not set properly.

Infusions change the character without changing the ratio: steep orange zest, a split vanilla bean or a spoonful of loose tea in the cream for 10 minutes, strain, and bring it back to a simmer before pouring.

Truffles as a gift

Truffles made with fresh cream are a refrigerator confection, so give them close to the day they are made and tell the person to keep them cold. Pack them in small paper cups inside a firm box so they do not knock together; the gift boxes collection has small boxes that suit a dozen. For chocolates that keep longer at room temperature, the truffles and bonbons collection has the professional versions, and the cocoa brownies use the rest of the cocoa.

Truffles reward getting one thing right. Weigh the chocolate and the cream, match the ratio to the percentage on the wrapper, and the rest is patience in the fridge and cold hands at the end.