Protein Flashcards
Primary Structure
Amino acids are joined together by peptide links
Secondary Structure
Involves the folding of the primary structure
The chain coils and forms a spiral shape
Cross-links give the protein definite shape and structure
Tertiary Structure
The pattern of folding polypeptide chains into 3D organisation
Can be fibrous: coiled, zig zag, straight
or globular
Lipoproteins
Casein
Lecithin
Nucleoproteins
Chromosomes
Chromoproteins
Haemoglobin
Myoglobin
Phosphoproteins
Casein
Lecithin
Supplementary Role
When foods that lack certain amino acids are eaten together they provide a full conplement of amino acids
Properties
Solubility Elasticity Denaturation Maillard Reaction Moist heat Gel formation Foam formation
Solubility
Most are insoluble in water
Except albumin in cold
and collagen in hot
Denaturation
Change in nature of protein chain
Heat
Agitation
Chemicals
Maillard reaction
Amino acid reacts with sugar in dry heat conditions to brown food
Gel formation
Gelatine can absorb large amounts of water to form a gel
If this is heated it liquifies and forms a sol
The sol cools, sets and becomes a solid
Foam formation
Whisking unfolds the protein structure and air bubbles form around it, forming foam
Functions of Structural Protein
Growth
Repair
Production of cells, muscle, skin
