Processing Study on Amidated Pectin by De-esterification of High Ester Citrus Pectin

High ester (methyl) citrus pectin (HM-pectin) was used to produce an amidated pectin under low temperature. Parameters such as galacturonic acid contents, degree of esterification (DE), degree of amidation (DA) and specific viscosity of the amide pectin were assayed. The results indicated that higher concentration of ammonia (4N) at low temperature (5℃) gives lessβ-elimination reaction, with better specific viscosity retained and increases the conversion of methoxyl groups to acid amide groups. Meanwhile a low amidation pectin would be produced with low concentration of ammonia (1N). And within a relatively short time of esterification(40min) at low temperature, either higher concentration or lower concentration processing with ammonia, the parameters such as galacturonic acid contents, degree of esterification (DE), and degree of amidation (DA) in the final products would be in accordance with the regulations for amidated pectin requirements of European Union.