Specialist Crafts · Article 10

Chocolate & Confectionery

A reference article · 3,300 words · 15 cited sources · last reviewed August 2026

Chocolate work is really two chemistry problems: getting one fat to crystallize into the right form, and getting sugar to either crystallize finely or not at all. Master those two and tempering, ganache, caramel, and showpiece sugar stop being separate crafts.

Almost everything a chocolatier does comes back to two ingredients behaving predictably: cocoa butter, the fat that has to crystallize into exactly the right form, and sugar, which you either coax into fine crystals or stop from crystallizing at all. Tempering, molded bonbons, ganache, caramel, and pulled-sugar showpieces look like five separate skills, but they run on those two ideas plus one more, water activity, which decides how long a filling keeps. Learn the three and the whole craft connects.

Where chocolate flavor comes from

Fresh cacao tastes nothing like chocolate. The flavor is built in three steps before a chocolate maker ever touches it. Fermentation, two to seven days, lets yeasts and bacteria work the bean’s pulp, killing the germ and generating the pool of free amino acids and reducing sugars that flavor will later come from. Drying brings the beans down to six to eight percent moisture and off-gasses harsh acidity. Then roasting at roughly 248 to 302°F (120 to 150°C) runs the Maillard reaction, the same browning chemistry behind toast and seared meat, between those fermentation precursors, and that’s where “chocolate” aroma actually gets created.

Turning roasted beans into chocolate is mostly a grinding problem. The nib is ground to a liquor, refined with sugar (and milk powder for milk chocolate) down to a particle size around 20 microns, because anything coarser than about 30 microns reads as gritty on the tongue, then conched for hours to days to coat every particle in cocoa butter and drive off the last of the acidity. Couverture is the professional coating chocolate, and it carries a high cocoa-butter content: generally at least 31 to 32% total fat and often 34 to 40%, which is what lets it flow into thin, even shells and temper to a proper snap. Compound coating swaps the cocoa butter for other vegetable fats so it needs no tempering, but it sets softer, has less snap, and in many places can’t legally be called chocolate.

Tempering: growing one crystal, on purpose

Tempering is the single most important skill in chocolate work, and it exists because cocoa butter is polymorphic: its fat can solidify into six different crystal structures, called Forms I through VI, each with its own melt point and stability. Only Form V gives finished chocolate everything you want at once: high gloss, a hard clean snap, the contraction that pops it out of a mold, resistance to bloom, and a melt just below body temperature.

The trick is that unstable forms crystallize more easily than Form V, so you can’t just cool melted chocolate and expect the good crystal. The classic curve is melt, cool, then rewarm. Melt fully to erase every existing crystal, cool while stirring to nucleate a mix of crystals, then rewarm to a precise working temperature that melts out the unstable Forms I through IV and leaves only Form V seeds behind to template the rest of the mass as it sets.

Milk and white chocolate sit lower because their milk fat and milk solids soften the cocoa butter. The working temperature is a ceiling, not a target to drift past: take dark chocolate above about 93°F (34°C) and you melt the Form V seeds and fall out of temper. On the bench, the most reliable method is seeding: stir finely chopped tempered chocolate into the warm melt in stages, so the added Form V crystals do the templating for you. The silk or Mycryo approach, adding about one percent of powdered Form V cocoa butter at working temperature, is even more repeatable. Good temper shows as gloss, a hard snap, and clean contraction; a knife tip dipped and held at 68°F (20°C) should set glossy and streak-free within three to five minutes.

When it goes wrong, the surface tells you which way. Chocolate that was worked too warm has too few good seeds, so it sets dull, soft, and streaky and later develops fat bloom, a grey film where cocoa butter migrates and recrystallizes into the slow-forming Form VI. Chocolate worked too cool has too many crystals, turns thick and matte, and casts heavy shells. Store finished chocolate at a stable 61 to 64°F (16 to 18°C) and below about 55% humidity to keep both fat bloom and sugar bloom (a gritty crust from condensed moisture dissolving surface sugar) away.

Molded and dipped work

A molded bonbon is built in a spotless, dry polycarbonate mold at around 68°F (20°C). You fill the cavities with tempered couverture, vibrate to knock out the air that would otherwise leave pinholes, then invert and pour out the excess so the clinging layer forms a shell about 2 to 3 millimeters thick. Once that sets, you fill with ganache or caramel to just below the rim, keeping the filling cool enough, around 79 to 82°F (26 to 28°C), that it doesn’t melt the shell, let it set, and cap it with a final flush layer of tempered chocolate. The whole system depends on contraction: a properly tempered shell shrinks as it sets and lifts cleanly off the mold wall, which is also what gives it that mirror shine. Cool it at 59 to 63°F (15 to 17°C), cool but not cold, because a refrigerator sets it too fast and leaves it dull and cracked.

Fillings that keep: ganache and water activity

A fresh pastry cream lasts days in the refrigerator; a sellable bonbon has to last weeks at room temperature. The lever that makes that possible is water activity, written a_w, the fraction of the water in a filling that is actually free for microbes and reactions to use, on a scale from zero to one. It’s not the same as how wet something is: sugars, glucose syrup, and polyols bind water, lowering water activity without drying the filling out. Most bacteria need a_w above about 0.90 and most molds are stopped below about 0.80, so the target for a room-temperature ganache is roughly 0.80 to 0.85, and lower for a long-keeping one.

You hit that target with humectants, ingredients that hold onto water. Swapping a portion of the sugar and cream for invert sugar (which also keeps the ganache soft and resists graining), glucose syrup, or sorbitol pulls the water activity down while keeping the texture supple. Stack a few more hurdles on top, a slightly lower pH, sometimes a little alcohol, and above all a fully sealed tempered shell acting as its own moisture barrier, and a dark ganache bonbon holds for three to four weeks or more. The ganache itself is a fat-continuous emulsion, so build it the way you would any emulsion: blend from the center outward or with an immersion blender kept below the surface, and add butter last and below 95°F (35°C) so the butterfat stays partly crystalline. Let it set slowly at 61 to 64°F (16 to 18°C) for a fine, snappy interior. Praliné, gianduja, and caramel fillings keep even longer because their water activity is naturally low.

Sugar confectionery: crystalline or glassy

Every sugar confection sits on one side of a single divide. Crystalline sweets like fondant and fudge are built on controlled, very fine sugar crystallization; glassy or amorphous sweets like hard candy, toffee, and caramel are supersaturated syrups cooled so fast that crystals never form. Which one you get is something you control, mainly with doctoring agents: glucose or corn syrup, invert sugar, and a little acid all interfere with sucrose crystals, so more of them pushes a batch toward glass while less of them, plus deliberate agitation, gives you fine crystals. The other variable is temperature, because in a boiling syrup temperature is a direct readout of sugar concentration.

Caramel is where this gets tasty. Cook it dry, melting the sugar alone, for a fast and intense but scorch-prone result, or wet, dissolved in water first, for a slower and more forgiving one. Soft caramels, made with sugar, glucose, and cream or butter, are cooked to roughly 244 to 257°F (118 to 125°C), and every degree or two noticeably firms the set. Their flavor is mostly Maillard browning from the dairy rather than pure caramelization (the thermal breakdown of sugar alone, which needs about 320°F, or 160°C). Fondant is the clearest illustration of crystalline technique: cook a syrup to soft ball, cool it undisturbed to about 104°F (40°C), then agitate the supersaturated syrup hard so it throws millions of microscopic crystals into a smooth paste. Fudge is the same move cooked a touch higher and beaten. Push past soft crack and you are making toffee and brittle, glassy and hard, where a single stray crystal can ruin the batch. Aerated confections branch off from here too: nougat whips hot syrup and honey into egg whites, and marshmallow does the same but sets the foam with gelatin.

Showpiece sugar

Cast and pulled sugar showpieces are their own discipline, and the modern medium is usually isomalt, a sugar alcohol cooked to about 338 to 356°F (170 to 180°C). It has largely replaced cooked sucrose for competition work for one reason: it’s far less hygroscopic, meaning it doesn’t pull moisture from the air and go sticky and cloudy the way sugar does within hours. Pulling sugar under a warm lamp folds fine layers of air into it for an opaque satin sheen, blowing inflates a warm ball like glass, and casting pours it clear into molds. Humidity is the enemy throughout, so showpiece work happens in a dry room and finished pieces get stored airtight with silica-gel desiccant.

Troubleshooting

The idea in one paragraph

Chocolate and confectionery are two crystallization problems wearing a dozen costumes. Cocoa butter has to be tempered so it sets as Form V, the one crystal that is glossy, snaps, contracts out of a mold, and melts just below body temperature, which you get by melting fully, cooling to nucleate, and rewarming to a precise ceiling. A bonbon then keeps for weeks because its filling’s water activity is pulled down with humectants and sealed inside a tempered shell, not because it is dry. And every sugar confection is a decision between fine crystals and none: doctoring agents and agitation give you crystalline fondant and fudge, while glucose and a fast cool give you glassy caramel, toffee, and pulled sugar, with the candy stages simply marking how much water you have boiled away.