These products differ in the degree of gel attained, manner of preparation of fruit, and ingredient composition. They are easily made at home. Jams are made from crushed or ground, whole fruit and usually have a thick consistency due to high pectin content. Marmalade is a jelly with pieces of fruit suspended in it. Citrus peel and juice are frequently the basis of marmalade.
Conserves are jams made from a mixture of fruits.
They usually contain citrus fruit, nuts, and raisins. Pectin is needed to provide thickening or gel formation. Pectin is formed from a parent compound, protopectin, during the ripening of fruit and during the cooking of underripe fruit. All fruits contain some pectin. Apples, crabapples, gooseberries, some plums, highbush cranberries, and citrus peel contain large amounts of pectin.