earliest sugar preserves were probably fruit pieces immersed in syrupy honey (the Greek term for quinces packed in honey, melimelon, gave us the word marmalade) or in the boileddown juice of wine grapes The first step toward jams and jellies was the discovery that when they were cooked together, sugar and fruit developed a texture that neither could achieve on its own In the 4th century CE, Palladius gave directions for cooking down shredded quince in honey until its volume was reduced by half, which would have made a stiff, opaque paste similar to today’s “fruit cheese” (spreadable “fruit butter” is less reduced) By the 7th century there were recipes for what were probably clear and delicate jellies made by boiling the juice of quince with honey A second important innovation was the introduction from Asia of cane sugar, which unlike honey is nearly pure sugar, with no moisture that needs boiling off, and no strong flavor that competes with the flavor of the fruit The Arab world was using cane sugar by the Middle Ages, and brought it to Europe in the 13th century, where it soon became the preferred sweetener for fruit preserves However, jams and jellies didn’t become common fare until the 19th century, when sugar had become cheap enough to use in large quantities Pectin Gels Fruit preserves are a kind of physical structure called a gel: a mixture of water and other molecules that is solid because the other molecules bond together into a continuous, sponge-like network that traps the water in many separate little pockets The key to creating a fruit gel is pectin, long chains of several hundred sugar-like subunits, which seems to have been designed to help form a highly concentrated, organized gel in plant cell walls (p 265) When fruit is cut up and heated near the boil, the pectin chains are shaken loose from the cell walls and dissolve ... mixture of water and other molecules that is solid because the other molecules bond together into a continuous, sponge-like network that traps the water in many separate little pockets The key to creating a fruit gel is pectin, long...flavor of the fruit The Arab world was using cane sugar by the Middle Ages, and brought it to Europe in the 13th century, where it soon became the preferred sweetener for... The key to creating a fruit gel is pectin, long chains of several hundred sugar-like subunits, which seems to have been designed to help form a highly concentrated, organized gel in plant cell walls (p 265) When fruit is cut up and heated near the boil, the pectin chains are