If you want to use quality chocolate like couverture for dipping, molding, or piping, you must temper it first.
To temper chocolate correctly, you need to melt it by slowly bringing it up to a temperature of 120 degrees F (50 degrees C), and then cooling and agitating it.
The two best ways to temper chocolate are in a double boiler or in the microwave. Small amounts of chocolate are harder to temper than big batches, so practice with at least 12 oz. of chocolate, or a full bag of chocolate chips.
If you’re using a double boiler, make sure the water is not touching the bottom of the upper pan. Bring the water up to a simmer, then turn off the heat before adding the chocolate, or keep it on low heat.
Always wipe the condensation off the bottom of the bowl when removing it from the heat; water can cause melted chocolate to “seize.”
To temper chocolate in the microwave, place the chocolate in a glass bowl and zap it on high power for 30 seconds at a time, stirring after each interval.
An accurate thermometer helps when tempering chocolate. But if you don’t have one, you can use your lips to gauge the temperature, since they are significantly more sensitive than your hands. Keep in mind that 120 degrees F is a bit warmer than your lips (not hot!), 80 degrees F will feel cool (although the chocolate will be mostly liquid), and that 90 degrees F is just slightly cooler than your lips. Do a “temper test” by dipping a knife point into the chocolate–it should harden within three to five minutes; or drizzle a little bit of the chocolate onto a piece of waxed paper. Let it set up for 5 minutes. If it’s glossy and hard, your chocolate is correctly tempered.
Cooling and Agitating
To cool your chocolate, you can either “table” or “seed” it.
To table chocolate, spread about ¾ of the melted chocolate on a marble slab with a putty knife, scrape it into a pile, and spread it thin again, until the chocolate cools to about 80 degrees F (27 degrees C).
Then return the chocolate to the bowl of remaining warm chocolate, stirring well; the chocolate should now be its ideal temperature of 88-90 degrees F (31-32 degrees C).
To seed chocolate, stir shaved or finely chopped chocolate into the warm melted chocolate; since the chopped chocolate is already “in temper,” you are encouraging the melted chocolate to form similar crystal structures.
Stir until the chocolate reaches body temperature when touched to your lip or the inside of your wrist.
Test for temper (as described above). If it does not harden, begin the process again.
White chocolate and milk chocolate have different tempering temperatures, so stick with dark (bittersweet or semisweet) chocolate until you feel comfortable with the process.
The two most common problems of working with chocolate are separating and seizing.
Separation happens when you get the chocolate too hot. The melting point of chocolate, especially that which contains a large amount of cocoa butter, is very distinct: one second, you have a bowl full of chocolate lumps, and a second later you have a silky-smooth bowl of melted chocolate. Because the change is so sudden, many people get impatient and make the mistake of turning up the temperature too high in order to speed up the process. When chocolate gets too hot, the cocoa butter separates from the solids, and there is no way to salvage it (although you can bake with it; it will taste fine in brownies). The best way to thwart separation is to use gentle heat and stir frequently.
Seizing occurs when moisture is introduced to melted chocolate. In the blink of an eye, you can go from a smooth bowl of liquid chocolate to a lumpy, grainy mess. Even the tiniest amount of liquid–a single drop of water, the moisture clinging to a strawberry, or the steam from a double boiler–will cause this kind of reaction. It is possible to rescue seized chocolate. The way to do this is, ironically enough, to add more liquid. Where a little bit of moisture causes seizing, lots of moisture will allow chocolate to relax again.