Kategorien: Alle - polysaccharides - viscosity - fermentation - stability

von Farah Hanim Vor 8 Jahren

259

GUMS AND STABILIZERS

Several natural gums and polysaccharides serve different roles in food and industrial applications due to their unique properties. Guar gum, soluble in cold water, provides high viscosity without forming gels.

GUMS AND STABILIZERS

Alginates

Derived brown seaweed
(Laminaria hyperborea)

Product of esterification name Propylene glycol alginate

In beverages, alginate act as a thickener & stabilizer

Provide excellent stabilizing effect in frozen products

the gel is thermo-irreversible.

can form gel in cold water in the presence of Ca ion

Made up of blocks of Dmannuronic acid (M-blocks) & Lguluronic acid (G-block)

Carrageenan

extract from seaweed

Ca and K ios are need to form bridges between adjacent double helix

lambda carrageenan does not have double helix form

Kappa and iota have structures that can form double helix

Kappa and iota carrageenan have the ability to form thermoreversible gels

3 types

 Iota (-carrageenan)
 Lambda (-carrageenan)
 Kappa (-carrageenan)

composed of linear galactan polysaccharides

Pectin

made up from citrus fruit

have a firm & short structure, clear & transparent, excellent flavour release

non heat reversible

ability to form gel increase as DE increase

Degree of Esterification >50%

High Methoxyl Pectin (HMP)

ued in jams

heat reaversible

form gel with Ca but lose gelling ability as DE increase

Degree of Esterification <50%

Low Methoxyl Pectin (LMP)

Xantham Gum

important for good flavor release and mouthfel

pseudoplastic

excellent stability to heat & pH

high viscosity in low concentration

completely soluble in cold water

product of fermentation of microorganisms

Xanthomonas campestris


Guar Gum

non gelling agent

high viscosity

soluble and hydrates fully in cold water

linear chain of mannose+galactose as side chain

Locust Bean Gum (LBG)

canned products, ice cream, beverages

do not form gel by itself

have to combine with xantham gum

do not dissolve in cold water (must be heated)

made up from galactose and mannose

why it is also called galactomannan gums

comes from seeds

Gum Arabic

used in confectionery products

least viscous and more soluble

dissolve in hot/cold water

structure contain galactose, rhamnose, arabinopyranose, arabinofuranose, glucuronic acid.

from Acacia trees

GUMS AND STABILIZERS

also known as food hydrocolloids which primarily function as thickening agent and gelling agent.