1. Functions of Proteins

2. B-3.02 -- Functions of Proteins in Food
Forms gels
Texturizes
Emulsifiers
Produce foams
Develops gluten
B Functions of Proteins in Food

3. B-3.02 -- Functions of Proteins in Food
Forms Gels
Protein gels
Mostly fluids locked in a three-dimensional mesh
Narrow melting and solidification range
Gels form between 50-61oC
Gels strengthened by:
Concentration of gelatin
Mineral salts
Gels weakened by:
Acid
Sugar
Fruit or vegetable pieces
B Functions of Proteins in Food

4. B-3.02 -- Functions of Proteins in Food
Texturizes
Protein texture/feel can be changed by denaturation
Texturized soy proteins (meat substitute)
Processed cheeses
B Functions of Proteins in Food

5. B-3.02 -- Functions of Proteins in Food
Emulsifies
Stable mixture of a fat and a water-based liquid
Proteins stabilize emulsions by acting as an emulsifier
Emulsifiers are molecules with polar and nonpolar end
Allows water and oil-based liquids to mix
Examples: milk, cream, butter, cheese
B Functions of Proteins in Food

6. B-3.02 -- Functions of Proteins in Food
Produce Foams
A foam is a gas suspended in a liquid or semi-solid.
Foams made by:
Bubbling gas through a mixture
Foaming milk for a cappuccino
Whipping or beating
Beating egg whites with a mixer
Depressurization
Whipped cream in a can
Soft drinks
B Functions of Proteins in Food

7. B-3.02 -- Functions of Proteins in Food
Develops Gluten
Gluten is a strong cohesive and elastic protein.
Developed in baked products, such as bread
Less developed in pie crusts, quick bread, muffins, biscuits, cakes, cookies
To prevent gluten development:
Add other grains such as rye and corn
Add more sugar
Add more liquid
B Functions of Proteins in Food