1. Egg yolk, vinegar and salt were added when mayonnaise is made. Egg yolk contains the
phospholipid lecithin which acts as an emulsifier to stop oil and water to get separated.
Vinegar plays the role of aqueous phase which allows the oil droplet to dissolve in it as
well as gives acidic flavour. Salt is added to give flavour and taste
2. During the experiment, it can be seen that the method of mixing the ingredient for
mayonnaise does affect the viscosity o the mayonnaise. When oil is slowly mixed into the
mixture, the oil is broken down into smaller droplet which dispersed into the continuous
phase as it is being mixed. This produced an oil-in-water emulsion. However, when oil is
added large amount into the mixture, the oil cannot be dispersed fully as before and the oil
will be mix as a larger droplets. This will give less viscous compare to the previous one
and it from water-in-oil emulsion instead. For the last experiment, if the mixture is added
to a large of oil, it will difficult to be broken down and instead of oil breaking down to
small droplet, vinegar will broke down into small droplets and dispersed in the oil where
the oil will be continuous phase forming water-in-oil emulsions well.
3. Other than mixing method, change in temperate or change in the ingredient used may