Jam

Jam from berries

Jam is a type of sweet spread or condiment made with certain fruits or vegetables, sugar, and pectin. Most jams are cooked. Uncooked or minimally cooked (less than 5 minutes) jams, called "freezer jam" (because they are stored frozen) are popular in parts of North America for their very fresh taste.

In the United States and Canada, jams are invariably made from mashed or ground fresh fruits (or in the case of vegetable jams, from cooked vegetables), and are never filtered. In United Kingdom and most Commonwealth countries, there are filtered and unfiltered jams, with the former resembling what Americans and Canadians call jelly. In this case the word "jelly" is usually reserved for a sweetened gelatine dessert. (An exception is bramble jelly, a seedless blackberry jam).

True North American jelly, however, is not filtered jam but is made by cooking transparent to translucent fruit or vegetable juice with sugar until it reaches the jelly stage (about 240° Fahrenheit), after which pectin is added to help the jelly achieve a firm set.

North American cuisine also distinguishes preserves, butters, and conserves from jams. Preserves use whole fruits, or large pieces of fruit or vegetable. Butters are made from certain orchard fruits, such as apples, pears, or apricots, lightly flavoured with such spices as cinnamon and/or cloves. A conserve is a preserve made with two or three contrasting fruits, or with two fruits and a fruit or nut butter, or a mix of fruits and nut. A jam made with citrus fruit and peel is called a marmalade.

Jam (and its variations) is often spread on bread and also as a culinary sweetener, for example in yogurt.

The use of cane sugar to make jam and jelly can be traced back to the 16th century when the Spanish came to the West Indies, where they preserved fruit, but the Greek technique of preserving quinces by boiling them in honey was included in the Roman cookery book associated with the name Apicius.

The proportion of sugar and fruit varies according to the type of fruit and its ripeness, but a rough starting point is equal weights of each. When the mixture reaches a temperature of 104 °C (219 °F), the acid and the pectin in the fruit react with the sugar, and the jam will set on cooling. However, most cooks work by trial and error, bringing the mixture to a "fast rolling boil", watching to see if the seething mass changes texture, and dropping tiny samples on a plate to see if they run.

An open jar of raspberry jam

How easily a jam sets depends on the pectin content of the fruit. Some fruits, such as gooseberries, redcurrants, blackcurrants, citrus fruits, apples and raspberries, set very well; others, such as strawberries and ripe blackberries, need to have pectin added. There are proprietary pectin products on the market, and most industrially-produced jams use them. Home jam-makers sometimes rely on adding a pectin-rich fruit to a poor setter; hence the popular old favourite blackberry and apple. Other tricks include extracting juice from redcurrants or gooseberries. Making jam at home used to be common, but the practice is declining, and the accessories, particularly the cellophane covers for jam jars, are becoming more difficult to find in some locations.

In the European Union, the jam directive (Council Directive 79/693/EEC, 24 July 1979) set minimum standards for the amount of "fruit" in jam, but the definition of fruit was expanded to take account of several unusual kinds of jam made in the EU. For this purpose, "fruit" is considered to include fruits that are not usually treated as fruits, such as tomatoes; fruits that are not normally made into jams, such as melons and water-melons; and vegetables that are sometimes made into jams, such as: rhubarb (the edible part of the stalks), carrots, sweet potatoes, cucumbers, and pumpkins. This definition continues to apply in the new directive, Council Directive 2001/113/EC (20 December 2001).

Joan Miró used blackberry jam as an art medium.

See also

* Lekvar
* Peanut butter and jelly sandwich (PB&J)

External links

* National Center for Home Food Preservation - How do I...Jam & Jelly
* Council Directive 2001/113/EC (20 December 2001)