In the days before refrigeration, reducing sweetened fruit pulp and canning it was a means of preserving the taste of summer year-round in Eastern Europe. The flavor was so exceptional, what was once a necessity became an important part of the culinary tradition.
The difference between fruit spreads is one of consistency. Here's how to tell them apart.
Fruit butters are made by cooking whole or halved unpeeled and, sometimes, unpitted fruit until tender and then forcing it through a sieve or food mill. Sugar, and sometimes spices and lemon juice, are added and the pulp is reduced by cooking until thick. No gelling agent, such as pectin, is used. The term fruit "butter" derives from its spreadability.
Conserves are jam-like mixtures of fruit, often with raisins or other dried fruit and sometimes whole or chopped nuts, liquor, and spices. They are cooked until they become very thick and chunky but are generally thinner than jam. They're typically spread on toasts, biscuits, crumpets and other breakfast breads or rolls. They also will work as a side with game meat or pork, or to fill a pastry like kołaczki.
Fruit curd is a creamy spread made with sugar, eggs and butter and, usually, citrus juice and zest. Lemon curd is the classic variety, but lime, blood orange, strawberry and cranberry curds can be found. A citrus curd is refreshingly tart, as opposed to more sugary jams and preserves. Fruit curds also can be used to fill tart shells and as a garnish.
Jams are made by cooking fruit purees with sugar and pectin until thickened. They are unstrained. Berries and other small fruits are most frequently used, but larger fruits work also. Good jam is characterized by an even consistency without chunks of fruit, bright color and a semi-jelled texture that has no free liquid. Jam also can be used to fill pastries like Polish Royal Mazurek.
Uncooked fruit purees mixed with sugar and pectin are called freezer jam because they are stored frozen. They are valued for their fresh taste.
In the United States and Canada, jelly is sweetened and jelled fruit juice. It is made by cooking down sweetened fruit (or vegetable) juices with pectin and an acid like lemon juice. Good jelly is clear and sparkling with no traces of pulp and it can be cut with a knife. In Britain, jelly refers to a fruit spread or preserve.
Marmalades are sweet and tangy fruit preserves that include the flesh and zest from citrus fruits, usually oranges.
Preserves are different from jams in that large or whole pieces of sweetened fruits (or vegetables) are cooked and jelled. It is not smooth like jam or jelly. Serbian slatko is a type of preserve in which the fruit is kept whole in a thick, sweet sugar syrup.
Fruit spread is a jam or preserves made with no added sugar.