Fatty oil: the oil that does not mix up with air through vaporization is called fatty oil. This type of oil is usually stored in seed.
Fatty oil may be of four types:
- Drying oil
- Semi drying oil
- Non drying oil
- Plant fat
Dry in oil: Drying oil gradually dries up to a thin membrane if it is kept on open place. So, this type of oil is used in varnish work.
Semi drying oil: It dries up very slowly if it is kept in open place. Example: Soybean oil, Sunflower oil, Mustard oil etc.
Non drying oil: This oil never dries up though it is kept in open place. Example: Caster oil.
Plant fat: This oil in summer remains as solid form but in winter it remains as liquid form. Example: Coconut and palm oil.