How and why we temper chocolate?
The short answer is that chemically, chocolate is composed of lots of different little crystals (six to be exact) but the desirable ones are called beta crystals. The development and formation of these beta crystals are what makes well-tempered chocolate.
If the cocoa butter rises to the surface, some people commonly think their chocolate's gotten moldy and toss it out. If you've tossed out your chocolate, you've tossed out perfectly good, but unattractive, chocolate.
If you made chicken stock and refrigerated it, would you toss it out when the fat collected on the surface? If you made vinaigrette and the olive oil rose to the surface, would you throw it away?
So why do we temper chocolate?
To avoid the dull white sheen on the surface of the chocolate.
That's what happens to chocolate that's not properly tempered: the cocoa fat rises to the surface and "blooms", making it unappealing and unattractive. When you buy chocolate, like a candy bar, the chocolate's been tempered and it should be nice and shiny and snap when you break it. If you leave your candy bar in a warm car and later open it up, often it'll become white and grey. The heat caused your chocolate to lose its temper. When you buy chocolate for baking, it should arrive well-tempered. But once you chop it up and melt it, the beta crystals change, the chocolate loses its temper, and you'll need to re-temper it again if you plan to use it as a coating. If you're going to cook with it, just use it in your recipe, as indicated.
Pages and volumes of technical research have been written about tempering chocolate, but here are the main reasons for all you home cooks out there:
- To avoid fat (and sugar) bloom, characterized by unappealing white streaks or blotches on the surface.
- To raise the melting temperature of finished chocolate so it doesn't melt on contact with your fingers.
- To preserve the keeping quality of chocolate by stratifying the fat.
- To cool chocolate quickly. Tempered chocolate cools fast, within 5 minutes.
- To give chocolate a glossy, shiny appearance, and a crisp, clean snap when you break it.
You don't need to temper chocolate if you're going to bake a chocolate cake or make chocolate ice cream. The only time you need to temper chocolate is when you need an attractive, shiny coating for candies that will sit at room temperature. You can get around tempering by dipping chocolates in melted, untempered chocolate and storing them in the refrigerator. Just remove them from the refrigerator a few minutes prior to serving them. The coolness of the refrigerator will stratify the cocoa fat.
There are many different methods for tempering chocolate. Some are really complicated, and some are really messy, especially for home cooks.
Many professional pastry chefs and chocolatiers can instinctively tell when chocolate is perfectly tempered by looking at it or touching a smidge of it to their lip. A thermometer is foolproof.
There is a simple 3-step method that's a snap for home cooks. All you need is an accurate chocolate thermometer (although a good digital thermometer will work).
How to Temper Chocolate
- Melt the chocolate in a clean, dry bowl set over simmering water, to about 115° F.
- Let it cool to the low 80°s F. Drop a good-sized chunk of solid (and tempered) chocolate in, which provides insurance by 'seeding' the melted chocolate with good beta crystals. While cooling, stir frequently. Motion equals good crystallization, aka, tempering.
- The last step is the most important. The chocolate must be brought to the perfect temperature, where it's chock-full of those great beta crystals. This occurs in most dark chocolates between 88° and 91° F. Remove what's left of the chunk of 'seed' chocolate, and your chocolate is dip-worthy: you can dip all the chocolates you want and all will be perfectly tempered. Don't let it get above 91° F of you'll have to begin the process all over again.
A tempering machine can do all of this for you, but it's not as much fun ;)