Pectin is a gum that is the methylated ester of polygacturonic acid. it is obtained from citrus peels and apple pomace. the degree of meth- ylation (dm) or esterification (de) refers to the percentage of acid groups which are present as the methyl ester. pectin is divided into two main groups: high methoxy (hm) pectin, having 50% or greater esterification, and low methoxy (lm) pectin, having less than 50% esterification. these pectins gel under different conditions. the lm pectins are subdivided into low methoxy amidated pectin and low methoxy conventional pectin. see pectin, high methoxy; pectin, low methoxy; amidated pectin.
