Protein lecture 4 Flashcards
Salt and it’s effect on protein structure
Different salts interact with proteins in different ways. Some salts increase protein solubility in water while others decrease it. In general a low concentration of salt is known to increase protein solubility while a high concentration of salt is known to decrease protein solubility.
Effect of protein on viscosity
The addition of proteins to a fluid increase it’s viscosity. The extent to which these proteins increases it’s viscosity depends on the concentration of proteins added to a solution and the extent to which proteins bond with another in the solution.
Effect of volume when it is dissolved in sol.
Proteins constantly change their volume when added to a solution (due to their movement?) and increases in volume increase in viscosity
Protein gels
Proteins are added to a solution, denatured and cooled to connect to one another to form a 3D protein matrix which traps water through osmotic pressure.
Thermally induced gels
Proteins are added to a solution are heated, change pH, and salts are added to denature and then cooled to form a gel which can be reversible or irreversible.
Intrinstic factors
- pH
- Protein concentration
- Temp.
Gelatin gelation process
Gelatin initially takes the form of triple helices connected together in powder. The powder is poured into hot boiling water and then the triple helices are unwound and denatured. When cooled down to below 30 degrees celsius the gelatin strands begin to connect with one another in a random manner due steric hindrance and lack of information as to where nitrogen and carbon bonds are located. As a result various crosslinks are made to connect all triple helices together to form a gel.
milk as a fat globule
Milk is a fat globule which consists of three layers one is filled with phospholipids the middle layer is filled with proteins and the layer on top of that is composed of proteins, enzymes and lipids.
