pectin(redirected from protopectin)
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pectin,any of a group of white, amorphous, complex carbohydratescarbohydrate,
any member of a large class of chemical compounds that includes sugars, starches, cellulose, and related compounds. These compounds are produced naturally by green plants from carbon dioxide and water (see photosynthesis).
..... Click the link for more information. that occur in ripe fruits and certain vegetables. Fruits rich in pectin are the peach, apple, currant, and plum. Protopectin, present in unripe fruits, is converted to pectin as the fruit ripens. Pectin forms a colloidal solution in water and gels on cooling. When fruits are cooked with the correct amount of sugar, and when the acidity is optimum and the amount of pectin present is sufficient, jams and jellies can be made. In overripe fruits, the pectin becomes pectic acid, which does not form jelly with sugar solutions. Commercial preparations of pectin are available for jelly making. An indigestible, soluble fiber, pectin is a general intestinal regulator that is used in many medicinal preparations, especially as an antidiarrhea agent.
A purified carbohydrate obtained from the inner portion of the rind of citrus fruits, or from apple pomace; consists chiefly of partially methoxylated polygalacturonic acids.
Biochem any of the acidic hemicelluloses that occur in ripe fruit and vegetables: used in the manufacture of jams because of their ability to solidify to a gel when heated in a sugar solution (may be referred to on food labels as E440(a))