Tempering in kitchen terms means bringing an item to a usable temperature. In pastry tempering can have a couple of more specific definitions. One referring to the method of heating and cooling chocolate to specific temperatures to select certain characteristics, and the other to a method of adding a hot liquid to some form of egg without cooking the egg.
Tempering Custards:
The method of tempering using a hot liquid and eggs is a lot simpler, requires no special equipment and for most people is a lot more useful, so that’s where I’ll start.
Tempering is used when making a creme brulee, or other custard such as creme anglaise, or creme caramel, but also for certain recipes of butter tarts and pecan pies. The technique of tempering is basically slowly adding the hot liquid, whether it be cream, or caramel, or whatever, while constantly whisking to distribute the heat, thus raising the temperature of the eggs above that which they could go normally without cooking. This is easy to do with a helper, but slightly more troublesome alone. With one hand to pour, and one hand to whisk that doesn’t leave a hand to hold the bowl while you whisk. One trick to to take a wet towel, twirl it around by one corner (as if you were going to flick it at someone) and place that in a ring around the base of the bowl. This will leave you with one hand to pour and one hand to whisk. A good rule of thumb is to add 10% on the first pour, make sure that that is well mixed, add another 20%, again whisking, then you can add the remaining in 1-2 additions. The whole mix should now be warmer than the eggs should be able to get without cooking, but should be smooth.
An alternative method if you’re not comfortable with the all-in-one method above is to take a few spoonfuls of the hot liquid to your eggs while mixing, then slowly add the now warmed eggs into the hot liquid as above.
Now on to the chocolate technique.
Tempering Chocolate:
The basic principles are that inside the cocoa butter in chocolate six types of crystals can be formed. Of the six, only two provide desirable characteristics. Have you ever melted chocolate for coating or dipping and had streaks form on the surface shortly after, or the chocolate doesn’t set up at all? To prevent this, pretty much the only thing you can do is to temper the chocolate before you use it.
Each individual chocolate formula differs from company to company and from product to product and thus requires slightly different tempering temperatures. The basic technique remains the same for all varieties, however.
First you raise the temperature, melting the chocolate, then the chocolate is cooled, possibly with the addition of finely chopped or chipped pre-tempered chocolate, and the whole mix is then re-warmed. There is extensive information online about the types of crystals and their characteristics, but it’s all a bit technical to go into here.
For the 3 main types of chocolate there are some rough temperatures (in C) to use as a guideline:
Dark: 45-50, 27-28, 31-32
Milk: 45-50, 26-27, 30-31
White: 45-50, 26-27, 30
All chocolate is pre-tempered when you buy it, and you can use this to your advantage if you chose to temper it.
