pectin

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pectin Plant tissues contain hemicelluloses (chemically polymers of galacturonic acid) known as protopectins which cement the cell walls together. As fruit ripens, there is maximum protopectin present; thereafter it breaks down to pectin, pectinic acid, and, finally, pectic acid, and the fruit softens as the adhesive between the cells breaks down.

Pectin is the setting agent in jam; it forms a gel with sugar under acid conditions. Soft fruits, such as strawberry, raspberry, and cherry, are low in pectin; plums, apples, and oranges are rich. Apple pulp and orange pith are the commercial sources of pectin. Added to jams, confectionery, chocolate, and ice cream as an emulsifier and stabilizer instead of agar; used in making jellies, and as an anti‐staling agent in cakes. Included in non‐starch polysaccharides.

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