Extraction, Characterisation, and Application of Pectin from Tropical and Sub-Tropical Fruits: A Review

Pectin, a polysaccharide, is ubiquitously found in cell wall of higher plants. It is traditionally used in the preparation of jam, jellies, and marmalades as a gelling agent. New applications of pectin continue to emerge, making pectin extraction and commercialisation an attractive investment. Commercially available pectin is extracted from citrus peels and apple pomace worldwide. However, a number of tropical and sub-tropical fruits by-products represent potential sources of pectin which can also be capitalised. It is to be noted that conventional extraction of pectin requires a lot of energy and involves the use of mineral acids. In line with sustainable development goals, studies have been undertaken to assess the efficiency of non-conventional green extraction methods, such as microwave-assisted extraction, ultrasound-assisted extraction, and enzyme-assisted extraction, on the yield and characteristics of pectin extracted from tropical and sub-tropical fruits. The present review article compares and discusses the effects of conventional and non-conventional pectin extraction techniques on the extraction of pectin from tropical and sub-tropical fruits by-products, as well as the potential applications of pectin extracted from these materials.