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" Why does my melted chocolate 'seize up' ? "

Dear Anne and Sue,

"I love making my own chocolate candies and use the water bath method to melt chocolate. From time to time the steam from the pot under the bowl gets in the chocolate and then it seizes up and ruins. What causes this and how can I repair the damage?"

— Anita Venkland


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Dear Anita,

Chocolate was once considered to be the food of the ancient gods, so perhaps one can expect it might have some idiosyncrasies. As you've found out, melting is one of them. Sometimes chocolate melts to a satiny pool of liquid chocolate, and sometimes it becomes a grainy mess.

Chocolate being melted, simply can't tolerate small drops of water. In this case, the steam escaping from the bottom of the double boiler is sufficient to make chocolate seize. The same thing will happen if you cover the pan in which chocolate is melting. Then moisture condenses on the inside of the lid and drips down on the melting chocolate... with the same result.
Once chocolate has seized it's not easy to coax it back to liquid form. Sometimes whisking a tablespoon of warm water into the chocolate works, then add more water a teaspoon at a time until the chocolate is smooth. Or try adding a few drops of vegetable oil or clarified butter (as it's water content has been removed). This will sometimes soften the seized chocolate enough that it will mix with other ingredients. Resurrecting it is always worth a try!

When melting chocolate make sure the water in the bottom of a double boiler is hot, but not boiling. Or consider melting chocolate in a very heavy saucepan with a metal ring placed on the element to insulate it from direct heat. The temperature of the chocolate should not rise about 115° F (46C), which is only as warm as tepid water. A microwave set at only 50% power, and checking it every 90 seconds, also works well. When it's "almost melted" the carry-over heat held in the chocolate usually finishes the job.

As strange as it seems, when larger amounts of water are used, the dynamics of melting change so that chocolate liquefies smoothly. When a recipe calls for melting bittersweet, semisweet, or white chocolate WITH liquid, use a minimum of 1 Tablespoon (15 ml) of water per ounce of chocolate. For unsweetened chocolate some sources recommend using at least 1 1/2 Tablespoons (20 ml) water per ounce.

Hope this helps!
Anne and Sue


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