Gums and stabilizers

CMC

Not all CMC is the same
30 producers make over 300 types of CMC
Anhydroglucose polymer with 100 to 3,500 units (Degree of polymerization = DP)
Degree of carboxymethyl substitution ranges from 0.4 to 1.2 unit (Type numbers are bout 10 times. DS = 4, 7, 9, 12 etc.)
Dilute solutions have pH about 7.0 with acid group ionized (free acid form at pH < 3.0)

CMC Uses

Binder and thickener
Retards ice crystal growth
Aids emulsion stability

Carboxymethyl cellulose

CMC - Na salt

Methocel

Syneresis inhibitor
Increases water absorption
Decreases fat absorption

Methyl cellulose

Methocel™

Functional properties of cellulose derivatives

Microcrystalline cellulose

Functional properties Water phase stabilizer - functions like oil phase in frozen desserts Forms colloidal dispersions - controls ice crystal formation Non-metabilizable fat substitute

Carrageenan

Galactose backbone Ester sulfate gives negative charge Gels with potassium (Kappa) Gels with calcium (Iota) Non-gelling (Lambda) Good stabilizer for milk proteins Suspender for chocolate in milk Milk gels with TSPP Part of ice cream stabilizer mix Water gels

Three main forms - often sold as mixtures. Kappa

Lambda

Iota

Typical Dairy Applications of Carrageenan

Comparisons of carrageenans

Reaction with proteins

Depends on number and position of sulfate groups Anion forms stable colloidal protein-carrageenan complex Protein - Carrageenan Interactions

Protein with a negative charge

Protein with a positive charge

Uses:

Stabilizer for chocolate milk, milk based puddings, emulsions Frozen desserts - inhibits ice crystal formation and retards melt down Bakery products - dough conditioner

Guar Gum

Galactomannan (Mannose (1-4) + Galactose (1-6) every other Mannose

MW 220,000 ± 20,000

Particle size affects viscosity and hydration

Cold water swelling - Turbid solutions

Pseudoplastic - shear thinning

Hydration increased by heating

High water binding

High viscosity form - up to 100,000 CP

Low viscosity from - up to 10,000 CP

Modifies properties when used with

Carrageenan

Xanthan

Food uses

Ice cram (prevents ice crystal formation, slow meltdown, heat shock resistance) Salad dressing (viscosity) Cheese (improves spreading)

Polymers of Mannuronic and Galacturonic acids varying widely in ratios of the two acids

Viscosity of 1% solution ranges from 10 to 2,000 CP as a function of molecular weight and calcium ion content

Precipitates below pH 3.0 Degrades above pH 6.5 Forms gels with calcium ions - 0.5 to 1.0% calcium Propylene glycol derivative improves stability to calcium and acid

Food functionality includes:

Water binding Gelling Emulsifying Stabilizing

Applications

Hot water desserts - gel without refrigeration (must account for calcium ions and water hardness) Dressings - thickening and emulsion stability Bakery products - fruit fillings, texture and gelatin frozen desserts - resist ice crystal formation

Alginate Gels

Extrude into calcium bath Use sodium alginate with a sparingly soluble calcium salt Regulate calcium availability by regulating pH Too much calcium gives grainy gels Too slow release gives weak gels

Propylene Glycol Alginate Ester Reduces

Precipitation at low pH Interaction with Ca ions Some interaction with fat "Slimy" mouth feel can substitute for fat Good foam stabilizer

Pectins 

Unbranched polymers of 200 - 1,000 Galactose units, linked beta1-4 Glucosidic bonds

Degree of esterification controls setting rate

>50% High Ester Pectins (HM) <50% Low Ester Pectins (LM) 70 - 85% = Rapid Set 44 - 65% = Slow Set

Calcium required to gel LM Pectins Amidatied LM Pectins used to gel natural fruit preserves High ester (HM) Pectins stabilize sour milk drinks - react with casein Low ester (LM) Pectins used for milk gels

Forms of Pectin

Locust Bean Gum

Galactomannan (D-Mannose (1-4) with Galactose (1-6) every 4th mannose

Molecular weight 330,000 ±30,000

Neutral - relatively unaffected by ions, pH.

Not soluble in cold water

Fully hydrated if heated 10 minutes at 80° C

Solutions are cloudy, off-white

Pseudoplastic - shear thinning, zero yield value

Modify properties of

Carrageenan

Xanthan Gum

Food uses similar to Guar Gum (See below) Locust Bean Gum

Guar Gum galacto-mannan ( 1-4) beta-D manno-pyranosyl, (1-6) alpha-D-galacto-pyranosyl polymer Guar Gum

Synergism in viscosity with wheat starch

High viscosity in cold water

High concentrations of sucrose reduce viscosity

Viscosity not affected by pH

Uses:

Elimination of syneresis

body and texture in frozen desserts

Dressings - viscosity and mouthful

Microbial polysaccharides

Xanthan - secreted by Xanthomonas camperstis

D-glucose 2.8 moles

D-mannose 3.0 moles

D-glucuronic 2.0 moles

All beta (1-4) linkages

Molecular weight - 2 - 50 x 106 Daltons

Xanthan

Backbone same as cellulose (1-4 Glucose)

Trisaccharide side chain at 3 position of alternated glucose monomer units.

Acid groups are beta-D-Glucuronic acid and pyruvic acid on 1/2 of terminal mannose units.

High degree of interaction between chains.

Molecular weight about 15 million.

Cold and hot water soluble

High viscosity at low concentration

Strongly pseudoplastic

Independent of concentration and shear rate

1% solutions gel-like at rest, but pour readily

Properties affected by ions

Freeze stable

Retort unstable - improved by 0.1% NaCl.

Uses of xanthan

Pastry fillings - 0.2% - low syneresis

Sauces and gravies - thermal stability, viscosity

Pourable salad dressings - pseudoplasticity

Dairy products - emulsion stability, viscosity control

Viscosity of Xanthan and Locust Bean Gums

Gum Arabic (Acacia)

Highly branched with beta-Galactose backbone

Molecular weight 250,000 - 750,000

Water soluble, fat insoluble

Low viscosity gum

Viscosity affected by pH and salts

Food uses:

Stabilizer for flavor emulsions

Encapsulated flavors

Water binding

Inhibit sugar crystallization

Gum Tragacanth

Polymer of Galacturonic Acid + Galactose + Galactose + Arabinose + xylose

Two components

70% Bassorine - swelling

30% Tragacanth - cold water soluble

Acid stable

High viscosity (varies with grade) 600 -4,000 CP at 1%

High cost

Food uses include:

Salad dressing (emulsifier)

Pickle relish (Increases drained weight)

Milkshake (reduce calories, thickener)

Pulpy beverages (stabilize solids - enhanced by Gum Arabic)

Ice Cream (surface tension related)

Karaya

Introduced as a Tragacanth substitute

Molecular weight about 950,000

Acetylated Galacturonic acid + Rhamnose + Galactose

Swells in aqueous environments

Used as adhesive

Food Uses include:

Powdered doughnuts

French dressing

Ice pops (prevents ice crystals, bleeding of free water)

Cheese spread (improves spreading)

Ground meats

Meringues

With Gum Arabic as protective colloid

Agar

From seaweed

Galactan

Insoluble in cold water

1.5% gel doesn't melt below 85° C

Temperature reversible gels

Used for gels in confectionery

High temperature tolerant gels

Gellan

Produced by Pseudomonas elodea

Composed of 2 beta-Glucose units + beta-Glucuronic Acid + Rhamnose

Molecular Weight 1,000,000

Insoluble in cold water

Gels with heat and Calcium

Typical use level 0.1 - 0.35%

Hard Gels

More tender gels with added Locust Bean or Xanthan