The preserving of fruits has long been an interest of the British cook. There is nothing quite so satisfying as seeing rows of brightly coloured jars in a store cupboard just waiting to bring a little delayed summer into the greyer months.
The term jam refers to a product made with whole fruit, cut into pieces or crushed. The fruit is heated with water and sugar to activate the pectin in the fruit. The mixture is then put into airtight vessels, principally glass but not exclusively. Jam can contain both fruit juice and fruit pieces, usually of just one fruit rather than a combination of several. Berries are the most frequently used, though larger fruits such as apricots, peaches, or plums can be cut into pieces and crushed for jam. A good jam should have a soft even consistency, a bright colour, a good fruit flavour and a partially jellied texture that is easy to spread.
The term curd refers to a product that is both a dessert topping and a spread. Most commonly it is made with lemon, though lime, orange or raspberry can be substituted. The basic ingredients are beaten egg yolks, sugar, fruit juice and zest which are gently cooked together until thick. The curd is then allowed to cool, forming a soft, smooth, intensely flavoured spread. Some recipes can include butter to improve the consistency.
Marmalade is a preserve with a bitter tang that is made from fruit, sugar, water and possibly a gelling agent. Marmalade most often refers to a preserve made from citrus fruits, most commonly oranges, though lime, lemon or grapefruit are also worthy of mention. An onion marmalade is sometimes produced as an accompaniment to savoury dishes. If the recipe includes sliced or chopped fruit peel, it should first be simmered in fruit juice and water until soft. The favoured citrus fruit for marmalade production in the UK is the Seville orange, so called because it was originally imported from Seville in Spain. Seville Oranges are higher in pectin than their sweeter counterparts which improves the set. American-style marmalades tend to be sweeter and not so bitter as the British preference.