Citrus Pectin is a high-molecular-weight heteropolysaccharide consisting primarily of alpha-1,4-linked D-galacturonic acid units with varying degrees of methyl esterification. It is extracted from dried citrus peel (lemon, lime, or orange) using hot dilute mineral acid, then purified and precipitated with isopropanol or as an aluminum salt.
Commercial grades include high-methoxyl (HM, DE >50%) for sugar-acid gels and low-methoxyl (LM, DE <50%) and amidated low-methoxyl for calcium-reactive gels in low-sugar products. Citrus pectin holds E440 designation in the EU and GRAS status with the FDA, with no ADI limitation established by JECFA. It is the workhorse gelling agent in the global food industry with annual production exceeding 60,000 tonnes.