WATER AND EMULSIONS:

Structure of ice

lattice = held together with hydrogen bonds

Formation of ice crystals

Must have a nucleus —> center of crystals (influenced by time and temperature)

Rapid freezing

larger number of small crystals —> better cellular preservation and quality

Slow freezing

larger cyrstals + cellular damage

Density

Ice is less dense than liquid because the lattice expands when it freezes

Water activity

Free water + bound water (measures accessibility of water for chemical reaction, ezymes, microbes)

Moisture content

Measures total water precense in a material

Boiling point

where vapor pressure of liquid equal pressure of surrounding = turns into vapor

Freezing point depression

freezing point pure water: 0 degrees celsius (32)

Melting point

the temperature at which it changes from a solid to a liquid

Boiling point elevation

water will boil faster at altitude —> boil al lower temperature (food will cook slower)

Emulsion

homogeneous dispersion of two component that repel each other (butter, mayonnaise, dressing, milk, ice cream, etc.)

Stabilizers

carbohydrate chain (hydrophilic) that thicken water phase to prevent lipid droplets from reuniting + separating out (xanthan gum, carrageenan)