Categories: All - function - interaction - stability - food

by Ang Chia Kee 8 years ago

302

Emulsfier

Emulsifiers play a crucial role in stabilizing emulsions, which are mixtures of two immiscible liquids. Various types of emulsifiers, including cationic, anionic, non-ionic, and amphoteric, are used depending on their electrical charges and chemical properties.

Emulsfier

Emulsfier

Function of emulsifier in foods

Peanut butter
•Inhibit oil separation
Potatoes
•Improve texture and whip •Reduce stickiness
Pasta products and snacks
•Improve texture •Reduce stickiness •Aid extrusion •Impart crispness
Cake and sponge improver
•Ensure good fat distribution in batter •Aid moisture retention in finished cakes •Facilitate mechanical handling •Improve aeration and volume •Better texture and shelf life
Bakery and other starch products
•Crumb softener •Volume enhancer •Dough conditioner

Hydrophilic-lipophilic balance (HLB)

-High lipophilic-low HLB (1-10) -High hydrophilic-high HLB (>10)

Emulsion destabilization

•Creaming •Flocculation •Coalescence •Ostwald ripening

Stabilization of emulsion through… (actions)

By macromolecules (physical barrier to coalescence)
-Protein -Gum
By fine particle
-Powdered silica -Basic salt -Plant fragment
Ionic interaction (DLVO theory)
Increase interfacial tension (with surface active properties)

Type of emulsifier

Amphoteric (both positive and negative charges)
•Various lecithins
Cationic (positive electrical charges) *toxic
•Amine compounds
Anionic (negative electrical charges)
•Stearoyl lactylates •Diacetyl tartaric esters of monoglycerides (DATEM) •Succinylated monoglycerides
Non-ionic (uncharged)
•Mono- and diglycerides •Sorbitan esters •Sucrose esters •Polysorbates •Polyoxyethylene glycol oleates (all contain an – oh functional group)

Function of emulsifier

•As surfactant •Starch complex forming ability •Modifying ability for oils and fats •Protein modifying ability •Antibacterial and antifungal •Plasticizing

Factors affect stability of an emulsion

•Degree of division of the inner phase •Quality/stability of the interfacial film •Viscosity of the outer phase •Ratio & the specific weight of the volumes of the two phases

Type of emulsion

w/o eg. Margarine
o/w eg. Milk