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Pectin
Pectin is a polymeric carbohydrate, which is a natural component of the cell wall and the middle lamella in all green land plants. Hence, it has an important influence on the structural properties of fruits and vegetables. Commercial pectins?are white, light yellow or yellow? powder without odour. Generally, pectin is a linear polysaccharide chain which consists mainly of galacturonic acid units. The galacturonic acid molecules can be esterified with methanol. According to the degree of esterification (DE), pectin is classified into high methoxyl pectin (HM) with a degree of esterification higher than 50% and low methoxyl pectin with a degree of esterification less than 50% (LM).
When ammonia is applied in the alkaline de-esterification process, some of ester groups have been replaced by amide group. Therefore, LM pectin is divided?into low methoxyl convertional (LMC) and low methoxyl amidated (LMA).
High Methoxyl (HM)
HM pectins are pectins with a degree of esterification above 50%.
High ester pectins
Apple High Methoxyl pectin (HM): The degree of esterification of HM pectin is above 50%, they can be applied into acidified milk drink、juice beverage、 high sugar jam(soluble solid >55%) and jellies、confectionery&pharmaceutical products according to their characteristics and different type.
Low Methoxyl Conventional (LMC)
?LMC are pectins with a degree of esterification below 50%.Commercial low methoxyl pectins are generally produced from plant material containing high methoxyl pectin. The transformation of high methoxyl pectin to low methoxyl pectin accordingly takes place under controlled conditions during the de-esterification process by treatment at either mild acidic or alkaline conditions.
Low ester pectins
Apple Low Methoxyl Amidated pectin (LMA): The degree of esterification of LMA pectin is less than 50%, the degree of Amidation is less than 25%，they can be applied into low sugar jam、 Yoghurt products、fruit preparations、bakery jam and fruit filling products.
Low Methoxyl Amidated (LMA)
If ammonia is used in an alkaline de-esterification process, a so-called amidated low methoxyl pectin will be produced. Besides galacturonic acids and galacturonic acid methoxyls, LMA pectin contains galacturonamide units in the molecular chain.
Amidated pectins
Apple Low Methoxyl Conventional(LMC):: The degree of esterification of LMC pectin is less than 50%, they can be applied into low sugar jam、 Yoghurt products、fruit preparations and bakery jam.
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