Cosa è la pectina

What is pectin?

A natural ingredient for every application needs

Chemically, pectin consists of the partial methyl esters of polygalacturonic acid and their salts (sodium, potassium, calcium and ammonia), with a molecular weight of up to 150,000 Daltons.

Pectin is obtained by aqueous extraction of the appropriate edible plant materials, mainly from citrus peel and apple pomace, followed by a selective precipitation using alcohol or salts. The raw materials used contain a large amount of pectin with superior quality and are available in sufficient quantities to make the manufacturing process more cost effective.

Pectin is usually classified according to the degree of methoxylation (DM). The degree of methoxylation is expressed as a percentage of esterified galacturonic acid units to total galacturonic acid units in the molecule of pectin.

Pectin produced by the normal extraction process contains more than 50% of methoxyl groups and is classified as high methoxyl (HM) pectin.

HM pectinHM pectin

Modification of the extraction process, or continued acid treatment, will yield conventional low methoxyl (LMC) pectin with less than 50% methoxyl groups.

LMC pectinLMC pectin

Some pectin can be treated during manufacture with ammonia to produce amidated low methoxyl (LMA) pectin with less than 50% methoxyl groups and from 5 to 25% of amidated groups.

LMA pectinLMA pectin

Commercial classification

Pectin is classified according to the degree of methoxylation (DM) as high methoxyl pectin (DM >50) and low methoxyl pectin (DM <50).
The degree of methoxylation influences the properties of pectin, especially the solubility and the gel forming characteristics.

HM pectins are capable of forming gels in aqueous systems with high contents of soluble solids and low pH values.

LM pectins are characterised by their ability to form gels in the presence of bivalent salts, normally Ca++ ions, in systems with low solids content and a wide pH range.

Pectin is classified by International Numbering System as E440(i) for high methoxyl pectin and conventional low methoxyl pectins and E440(ii) for amidated low methoxyl pectin.
 

Pectin classificationPectin classification