Preparation of vegetable ghee involves ?

The preparation of vegetable ghee is based on a chemical process called hydrogenation — the addition of hydrogen atoms to unsaturated compounds. In this process, vegetable oils, which contain unsaturated fatty acids (with double bonds), are converted into saturated fats (with single bonds), resulting in a semi-solid product known as vegetable ghee or vanaspati ghee.

Vegetable oils like soybean oil, sunflower oil, or cottonseed oil are liquid at room temperature because they contain multiple double bonds (C=C) in their hydrocarbon chains. During hydrogenation, hydrogen gas (H₂) is passed through the heated oil in the presence of a finely divided nickel (Ni) catalyst at a temperature of about 200–250°C.

The reaction can be represented as:
RCH=CH₂ + H₂ → RCH₂–CH₃

This reaction converts the double bond into a single bond by adding hydrogen atoms, turning the liquid oil into a semi-solid fat. The resulting ghee has improved texture, shelf life, and oxidation stability.

Key Steps in the Process:

1. 
   

   Heating the oil to 200–250°C.

   
   


2. 
   

   Passing hydrogen gas through the oil.

   
   


3. 
   

   Using nickel catalyst (Ni) to accelerate the reaction.

   
   


4. 
   

   Filtering the mixture to remove the catalyst after completion.

   
   

Applications and Importance:

• 
  

  Produces vegetable ghee, a substitute for butter and animal fat.

  
  


• 
  

  Used in food industries for cooking and baking.

  
  


• 
  

  Increases shelf stability and melting point of oils.

  
  

Key Facts:

• 
  

  Reaction Type: Hydrogenation

  
  


• 
  

  Catalyst: Nickel (Ni)

  
  


• 
  

  Temperature: 200–250°C

  
  


• 
  

  Reactants: Unsaturated vegetable oils + Hydrogen gas

  
  


• 
  

  Product: Saturated fat (vegetable ghee)

  
  

✅ Correct Answer: C) Hydrogenation