Water and interactions in water solution
Many foods as well as body cells contain mainly water.
A knowledge of water and of the forces acting in water solution is the basis to understand in a phenomena occurring in foods and in the cells.
Water structure
Hydrogen bond between two water molecules
Hydrogen bond in water solutions between different organic compounds
Van der Waals interactions
Non covalent interactions between non charged molecules.
Ions solvations in water solutions
Molecules organize themselves around the solute
Behaviour of oil in water
Which is the driving force of this phenomenon?
Behaviour of oil in water
Behaviour of oil in water
Behaviour of oil in water
Behaviour of oil in water
Behaviour of oil in water
Behaviour of oil in water
Emulsifiers
These are substances that, due to their peculiar chemical structure, are able to combine two different phases in a stable manner.
They are fundamental to many food preparations.
Emulsifiers
Emulsifiers
Emulsifiers
Emulsifiers
Emulsifiers
Polar and apolar
- Polar-hydrophilic
- Apolar-hydrophobic
- Polar:
- Charged groups COO- NH3+
- OH groups (carbohydrates)
- Apolar:
- Alkyl chains (CH3-CH2-CH2….)
- Aromatic rings
HLB scale (Hydrophilic-Lipophilic balance)
- Scale spans between 1 a 20
- Hydrophilic emulsifiers have high HLB value
- Lipophilic emulsifiers have low HLB value
- Lecitin
- Mono and diglycerides
- Sorbitol derivatives
- Sucrose esters
