Boiling involves the continued heating of foods in liquid at a temperature of 100°C

When you're heating liquid for boiling foods, you'll know it has reached the boiling point, or 100°C, when it bubbles rapidly. Liquids suitable for boiling foods include water, stock, milk and court bouillon.

A wide range of foods can be boiled, including vegetables, eggs, pasta, rice, joints of meat (particularly those of a tougher nature, such as silverside, brisket, legs of pork and mutton), fish, poultry, sauces and soups.

Some foods are best boiled by placing them in cold water and gradually bringing the water to the boil. Other foods are best placed directly into boiling water.

Foods best boiled from a cold water start include:

• stocks so that the maximum flavour is extracted

• root vegetables such as parsnips, carrots and turnips that require a longer cooking time

Foods best placed directly into boiling water include:

• green vegetables so that they cook quickly with a maximum retention of flavour and nutrients

• large cuts of meat, such as leg of mutton, to seal in the flavour.

While food is boiling, scum may rise to the top. This scum should be removed, especially while cooking soups and sauces, as the scum could taint the flavour and affect the colour of the food.

During cooking, the boiling liquid will reduce through evaporation. It is important to make sure that the food is completely covered with liquid at all times while cooking, so take care to top up the liquid if necessary. You may like to use a lid to reduce evaporation - this will also speed up the boiling process. Don't use a lid with green vegetables.

Selecting the correct saucepan or pot will also make a difference to the boiling process. For example, you should choose a large pot to boil pasta, as it needs a lot of water. Also use a wooden spoon as it won't get hot or scratch the saucepan.

When using a saucepan for boiling, simmering or poaching, always make sure you place the pan with the handle pointing inwards or to the side and never over the edge of the stove. This way it cannot be knocked by passers by.

Simmering

Simmering is a slightly more gentle method of cooking than boiling. Liquids are heated to the boiling point and then maintained at a temperature of 95-98°C. While simmering, the movement of the liquid is not as rapid as boiling liquid and tiny bubbles will rise to the surface.

Meats, poultry, stocks, soups and sauces are all foods that can be simmered. Some preparations require a combination of boiling and simmering.

Blanching

Blanching is a cooking method where food is scalded briefly in water. The food is then rinsed in cold water to refresh it.

Starting the blanching process from cold water causes the cells of the food to open and release impurities. The following are good applications for cold water blanching.

• Whitening meats such as bacon.

• Removing excess salt from meat that has been kept in a brine solution.

• Reducing the strong tastes of vegetables such as turnips or Swedes.

• Removing blood and impurities from bones.

Starting to blanch with hot water causes the cells to close and seal in the flavour and natural juices of food. The following are good applications for hot water blanching.

• To remove the skin from fruits or vegetables, such as tomatoes

• To par cook green vegetables