By the term Rancidity, We mean that Oxidation of fats..
It means that whenever there is Oxidation of Fatty acids or Oils Products the whole process is known as Rancity.
Rancidity provides unwanted Smell and Flavour ...

In some cases, however, the flavors can be desirable like in Cheese How older the Cheese it is said to be the good or best taste it has.
It has Disadvanteges lyk. It helps to degrade the nutritional facts ,Proteins or Carbohydrates present in it...

Corrosion ===============
By this term we mean  that it is the process of slow destruction of metals layer by layer ...
 Corrosion degrades the useful properties of materials and structures including strength, appearance and permeability to liquids and gases.
It can be reduced by the following methods like..
2.Chromate Conversion
These Helps to increase the resistance .....

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