Chocolate products, including chocolates with no added sugars, typically go through a melting process before they get to the end customers.
This process is very delicate because chocolates contain both proteins and carbohydrates that can overhead and lose their flavour qualities easily. When chocolate overheats, it becomes dull in flavour and looks lumpy.
If you are melting chocolate and you do overheat it, you can’t save it. Unfortunately, if this happens, you have to throw it out and start again. Overheating milk chocolate is especially easy because it contains dairy that burns very easily. You can melt the chocolate either in a microwave or in a boiler. In any case, you want to be present during the entire process and stir the substance often so that it doesn’t develop hot spots that can lead to overheating.
When melted chocolate interacts with water, it seizes up and thickens, which is why you need to make sure that there is no water or steam around when you are melting the chocolate. If you are planning to dip strawberries or baked goods in chocolate, make sure that their surfaces are dry and contain no water on them. When melted chocolate cools off without tempering, parts of it turn into crystals. These crystals make the chocolate become soft and taste dull.
Tempering means gentle heating of the chocolate substance resulting in the dissolution of undesirable crystals. Since desirable crystals, also known as beta crystals, take time to form, chocolate needs time to cool down. The range of temperatures for tempering is between 115F and 120F. Milk chocolate needs tempering at lower temperatures that bittersweet dark chocolate because of the difference in the behaviour of cocoa butter in it.
There are several procedures you can use to temper chocolate at home. No matter the procedure, the goal is to have the chocolate form a large number of small desirable crystals that are appealing both in texture and taste.