Certo is a name brand commercial pectin produced by Kraft Foods. It comes in a range of varieties, depending on your needs, but in general, it’s used to thicken jams and jellies. Certo, like other pectins, reduces the cooking time needed for fruit- and vegetable-based condiments that need thickening -- such as jams, jellies, salsas and relishes -- and helps them achieve their ideal degree of gelling and thickness.

Pectin is a naturally occurring soluble fiber that’s found in many fruits and vegetables. It is found in high quantities in some fruits, such as apples and citrus fruits, whose peels are naturally high in pectin.

When pectin is added to foods during cooking, it is reduced slightly -- as a result of cooking, as liquid from foods evaporates -- and it thickens when in the presence of sugar and acid, such as lemon or lime juice. Too much sugar or acid can lead to a hard, non-spreadable food, such as a jam or jelly, while a runny jam or jelly is the result of not enough sugar, acid or pectin.

All Certo products are made with pectin extracted from lime peels. There are three varieties of Certo available: the original blend in crystal format, the original blend in liquid format, and Certo light, which is available as crystals only. Certo light helps jams and jellies gel with less added sugar.

Liquid Certo is used to make no-cook jams or jellies. The pectin can be added directly to mashed and cooked fruit, and when left to sit, it will automatically gel jams and jellies.

Certo original is the original pectin product from Kraft. It is used for cooked jams and jellies, as well as for salsas or relishes that require thickening. Unlike liquid Certo, Certo original comes in crystals, and will only help foods thicken if it is heated after adding.

Certo light, like Certo original, is a crystalized pectin product. However, the pectin is designed to work with less added sugar, which reduces the overall carbohydrate and calorie count of a finished jam or jelly.

In addition to helping jams and jellies thicken, pectin also improves the color and taste of foods thickened with it. It does so by reducing the cooking time for jams and jellies.

Fruit- or vegetable-based jams, jellies, salsas and relishes will all thicken naturally if cooked for long enough -- moisture will evaporate and the mix will condense. The long cooking times required for this to happen to affect the color, texture and taste of the foods.

Pectin reduces the cooking time needed for thickening, which means that the natural colors, tastes and textures of foods are better preserved.