Luokat: Kaikki - hydrocolloids - stabilization - solubility

jonka AMIRA IZZATI BT.BORHAN 8 vuotta sitten

190

food ingredients : gums and stabilizers

Hydrocolloids, such as gums and stabilizers, play critical roles in various food and industrial applications. These substances can function as gelling or texturizing agents, thickening agents, and stabilizers for emulsions and suspensions.

food ingredients : gums and stabilizers

Gum and stabilizers

main classes

chemically modified
cellulose

example

hydroxypropylmethylcellulose ( HPMC )

carboxymethylcellulose ( CMC )

used in fried food

improve adhesion of batter

retard loss of moisture

create barrier to oil absorption

modify flow charateristics

stabilizing

gelling when heated and return to origin viscosity when cold

akaline treatment

extract from plant parts
Pectin ( peel of citrus fruits )

low methoxy pectin ( LMP )

jelly

low-sugar jams

yoghurt fruit

gelling properties

wide pH range ( pH 1-7 )

low solids

presence of calcium ions

sub-groups

amidated

very reactive to calcium ions

conventional

less reactive to calcium ions

degree of esterificatio < 50%

high methoxy pectin ( HMP )

gelling

classified

slow set

ex : very acids fruit jam

avoid premature gelation

rapid set

ex : whole fruits jam

ensure uniform distribution

low pH

high solids ( sugar )

heat irreversible

excellent flavour release

clear and transparent

short structure

firm

degree of esterification > 50%

extract from tubers
Konjac glucomannan ( K. Konjac tuber)
microbial gum
Xantham gum (fermentation with Xanthomonas campestris)

suspending

pseudoplastic

resistance to heat and pH

produce high viscosity at low temperature

completely soluble in cold water

extract from seaweeds
Alginates ( derived from brown seaweeds )

heat stable gel

martini drinks

onion rings

emulsifier

low-fat mayonnaise

thickener

stabilizing effects

dry mix fruit drinks

thermo-irreversible

can form gel in cold water ( present calcium ions)

high guluronic acid

good heat stability

strong

brittle gel

consist

guluronic acid

mannuronic acid

Carrageenan

lamda

cannot form gel

iota

elastic gel

kappa

thickening

moisture retention

gelation

suspension

firm and brittle gel

required cation to gelation

calcium ions

potassium ions

can form thermoreversible gels at low concentration

ability to reacts with milk protein

extract from seed
Guar gum

water binders

stabilizers

viscosity builder

very stable at pH 4.00 - 10.00

non-gelling

more highly substituted than Locust bean gum

Locust bean gum ( Carob bean's seed )

used in :

processed meat

ice cream

beverages

desserts

sauces

canned food

inhibition syneresis

stabilizing agents

non ionic ( stable in pH 3.5-11.0 )

derivatives from exudation or sap of tree
Gum Arabic ( Acacia senegal L's sap )

function

promote stabilization and emulsifier

soft drinks

beer beverage

to retard crystallization

commonly used in confectionery products

properties

work well with Xanthan for thickening

most soluble

least viscous

can dissolve in hot and cold water

flavorless

colorless

odorless

contains

small amounts of :

potassium

magnesium

calcium

protein

glucuronic acids

arabinofuranose

arabinopyranose

rhamnose

galactose

Factor effect on gum

distribution of side chains
number of side chains
type of side chains
monosaccharides composition
molecular weight

Hydrocolloids

formation of film
encapsulation
control of crystallisation
suspension of particulates
stabilisation of emulsion
gelling or texturizing agent
thickening agent