Gums and Stabilizers
Types and its properties
Gelatin
-Only derived from animal sources
-Collagen hydrolyses into gelatin
-Acid process give type A gelatin
-Alkali process give type B gelatin
-Type A gelatin negatively interact with anionic polymers
Xanthan gum
-Soluble in cold and hot medium
-Stable to heat, pH and high salt concentration
-Resist many enzymes
-
Locust bean gum
-Slightly soluble in cold water
-Require heat to achieve full hydration and maximum viscosity
Konjac
-In flour form, swells slowly at cool temperature
-As pseudoplastic
-Form elastic, thermally irreversible gel when set with alkali and heat
-Stable at pH 3-9
Gum Arabic
-Water soluble
-Low viscosity
Guar gum
-Soluble in cold water
-Hydrate quickly to produce viscous pseudoplastic solutions
-Stable over wide pH range
-Degrade at pH extreme at high temperature
Gellan gum
-With low acyl content, form hard,non-elastic, brittle gels
-With high acyl content, form soft, elastic, non-brittle gels
Agar
-Form gel at about 35C
Cellulose gums
Example: Carboxymethylcellulose (CMC)
-form firm gel above 50C
-form weak gel above 90C
Alginate
-Form gels with acid and divalent ions (Ca+)
-Water soluble
Pectin
Low methoxyl amidated (LMA) pectin
-25% degree of amidation (DA)
Low methoxyl (LM) pectin
-Less than 50% DE
-Form gels with Ca+ ions
High methoxyl (HM) pectin
-At least 50% DE
-Form gels at low pH, high soluble solids
Carrageenan
Kappa Carrageenan
-Fully soluble in cold water
-Strongest gel, but susceptible to syneresis
Lambda Carrageenan
-Require heat to dissolve
-Cold dispersion (calcium salt swells,
form thixotropic solution)
-Does NOT jellify
Iota Carrageenan
-With the exception of the sodium salt, normally swells
greatly but dissolves slightly in cold water
-No syneresis, gellify at higher temperature than Kappa carrageenan
Function
Secondary function
Stabilization of emulsions
Suspension of particulates
Control of crystallization
Encapsulation
Formation of film
Primary function
Thickening agent
Gelling or texturizing agent
Classification
Gelling agent
Thermally irreversible
Alginate
High methoxyl (HM) pectin
Konjac mannan
Locust bean gum
Thermoreversible
Gelatin
Agar
Kappa carrageenan
Iota carrageenan
Low methoxyl (LM) pectin
Gellan gum
Methyl cellulose and hydropropyl methyl cellulose
Xanthan gum
Thickener
Xanthan gum
Carboxymethylcellulose
Methyl cellulose and hydroxypropyl cellulose
Galactomannans (guar and locust bean gum)
Source of hydrocolloids
Modification of natural
hydrocolloid
Hydroxypropyl guar
Low methoxyl pectin
Proplyene glycol alginate
Starch derivatives
Hydroxypropyl starch
Cellulose derivatives
Carboxymethylcellulose, Methylcellulose,
Hydroxypropylcellulose
Animal
gelatin, caseinate, whey protein
Microbial
Xanthan gum, gellan gum
Algal
agar, carrageenan, alginate
Botanical
cellulose, gum Arabic, starch, guar gum,
locust bean gum, konjac glucomannan
