Working with Royal Icing
When it comes to royal icing many people seem to shy away from it and are worried that it is too difficult to get right. However, with a little practice you will discover that royal icing is incredibly versatile and can be used in many ways to decorate your cakes. It can be used to cover marzipanned fruit cakes, decorate cookies or piped to make a whole host of cake decorations.
Royal icing is made from egg whites (or dried egg albumen), water and icing sugar. If you are using fresh egg whites then you will need to add a few drops of lemon juice or vinegar. You can also buy packets from the supermarket or cake decorating supplier now that you just add water to. Whilst you can make it by hand, royal icing needs a lot of mixing so it is best to use a food mixer or electric hand whisk if you have one. If you are beating the icing with a machine, take care not to overbeat it as this can add too much air, making the icing difficult to work with. If you are using the icing to cover a cake you can add 1-2 teaspoons of glycerine to make the icing softer and easier to cut. Royal icing should be coloured with glucose and glyceride free liquid food colours.
The consistency of the royal icing will need to be altered depending on what you are planning on using it for.
Off peak stage
To test if your icing has reached the off peak stage, Beat the royal icing with your mixer then stir it with a palette knife or spoon and pull it out of the icing. The tips of the peaks that this leaves should just bend over. Icing at this consistency is used for pressure piping, drop line work, piping scrolls and writing.
To make a firmer royal icing stir in one tablespoon of icing sugar per 175g of royal icing (make sure you just stir it in and not beat it). If it becomes too thick you can thin it slightly by add 1 drop of water at a time. This is used when you need the icing to hold its shape firmly, such as when you are piping flowers or adding details like hair or fur.
Rubbing royal icing on a board or clean work surface with a palette knife will help to get rid of air bubbles and make the icing appear smooth. This is an important step when you are covering cakes with royal icing to make sure you get a good, smooth finish.
This icing is used for making run-outs, when you flood a piped outline with thinner royal icing. It is good for making letters or numbers and flat panels of decoration. To produce the correct consistency you need to rub down the icing on the work surface to expel the air bubbles then add enough cold water until it takes about 10 seconds to flow back together when cut through with a palette knife.