Pectin, a natural polysaccharide commonly used as a gelling agent, thickener, emulsifier, and stabilizer in food with the European food additive number E440. This ingredient is mainly made from citrus peel and apple pomace, and commonly used to gel jams and jellies.

Sources
Pectin occurs naturally in plants and can be found in the cell walls and in the middle layer of the cell of most vegetables and fruits. The sources for commercial production of pectin mainly come from apple pomace and citrus peel. Both derived pectin are high methoxyl pectin.

1. Apple pomace
Apple pomace is the main by-product of apple juice manufacturing. Apples are first processed into juice, and the remaining pomace is used to make pectin. Dry pomace contains around 10% to 20% pectin.

Apple pectin can be used as a thickener in dairy products, a gelling agent for jams and jellies, a blending agent in fruit drinks and a stabilizer in various food processing.

2. Citrus peel
Citrus peel is the most common raw material used to produce pectin than apple pomace as high in pectin. Citrus pectin refers to pectin extracted from the peels of citrus fruits such as lime, lemon, orange and grapefruit.

Citrus peel is the main by-product of citrus fruit processing. Its pectin content accounts for about 20-30% of the dry weight. Compared with other types of pectin, it has strong gelation, high esterification degree, and large molecular weight.

3. Other sources
Pectin content varies according to the types, origin, maturity, storage period and manufacturing processing of plants. The following fruits also contain pectin but with lower content compared with the above two main sources:

Apricot
Blackberry
Cherry
Peach
Pineapple