It really helps to have a suitable thermometer. In the Womanís Weekly test kitchen we use an infrared thermometer, so it doesnít come into contact with the chocolate so it stays clean. These can be bought from specialist chocolate equipment shops and also from electronic stores such as Maplin.
Why do you need to temper chocolate?
Chocolate contains cocoa butter and it's this cocoa butter that requires tempering. When cocoa butter is warmed it melts, then as it cools it re-crystallises and becomes solid again.
Without getting too technical, there are various patterns that the crystals can take; if it crystallises correctly then the chocolate will have a shiny even-coloured surface and it will have a snap to it when it's broken.
However, if it's not tempered properly then it will take a very long time to set and the surface will look cloudy, and may have a greyish mottled look to it and it will be soft.
Also when chocolate is tempered properly it will contract as it sets and it will then release from moulds easily; if it's not tempered properly then it tends to stick to moulds.
With tempering the chocolate is melted so that all the cocoa butter crystals dissolve, then the chocolate is cooled to the temperature where the right sort of crystals start to form, then the chocolate is warmed again to a working temperature.
If you're buying couverture from a specialist supplier, then it's usually possible to buy it as "coins" which are like chocolate buttons and they are quick to use. If you use a block of chocolate then it will need to be chopped before melting, so that it melts evenly.
One method of tempering is "tableing" where a worksurface is used to cool the chocolate. It's easiest to work on a marble or granite worksurface spread out the melted chocolate it will cool quickly, but any non-porous surface can be used, but it will just take a bit longer.
Dark, milk and white chocolate all require different temperatures, and even different brands of chocolate may vary slightly, but as a guideline follow these temperatures:
Initial warming, cooling, re-warming
Dark Chocolate 50°C 27°C 31-32°C
Milk Chocolate 45°C 25°C 29-30°C
White Chocolate 40°C 24°C 27-28°C
You will need:
Chocolate, dark, milk or white
Marble slab, optional
Table" method of Tempering
1. Melt the chocolate to the temperature given in the chart above, depending on what type of chocolate you're using.
2. Pour about 2/3rds chocolate out onto a worksurface to cool it down so the right sort of crystals start to form. The easiest way to spread it out is to use a palette knife and to use a paint scraper to scoop the chocolate back up to the centre of the board before spreading it out again. Repeat this spreading until the chocolate starts to thicken slightly. The chocolate on the table should then be at the 2nd temperature given in the chart above.
3. Scrape the chocolate on the table into the bowl with the reserved chocolate and mix. The chocolate should then be at the 3rd temperature in the chart. If it's too warm then "table" some of it again to cool it. If it's too cool, then warm it gently. It's a good idea to dip a knife into the tempered chocolate and lift it out to see how quickly the chocolate sets, this will give an indication to whether it's been tempered properly.