We use groundnut oil every day in our kitchen, but very few people actually know how it is made. Is it directly squeezed from peanuts? Are chemicals used? What happens inside an oil mill? In this article, we will walk through the complete journey of groundnut oil – from raw groundnuts to a pure, natural bottle of oil on your table.

1. Selecting High-Quality Groundnuts

Everything starts with the quality of the groundnut (peanut) itself. A good oil mill will:

• Use clean, matured, well-dried groundnuts
• Avoid spoiled, mouldy or insect-damaged seeds
• Prefer peanuts with higher natural oil content

High-quality seeds not only give better oil yield but also improve taste, aroma and shelf life of the final oil.

2. Cleaning and De-Shelling

Before extracting the oil, the groundnuts are cleaned to remove:

• Dust and sand
• Small stones or foreign particles
• Broken shells and stems

The nuts are then de-shelled (if not already) so that only the kernels are used for oil extraction. Clean kernels mean cleaner oil with fewer impurities.

3. Light Roasting (Optional but Common)

In many traditional mills, groundnuts are lightly roasted before pressing. This:

• Enhances the natural nutty aroma of the oil
• Helps improve oil extraction efficiency
• Reduces moisture content in the seeds

Roasting is carefully controlled. Over-roasting can spoil taste and colour, while very low roasting may not release enough flavour.

4. Oil Extraction – Wooden Ghani or Expeller

This is the heart of the process – where oil is actually pressed out of the peanuts. Two common methods are used:

a) Cold-Pressed / Wooden Ghani

In a wooden ghani or low-speed expeller:

• Groundnuts are crushed slowly at low RPM
• No external heat or chemicals are added
• Natural temperature is maintained within safe limits

This method preserves natural nutrients, Vitamin E and antioxidants, and is ideal for health-focused families.

b) Traditional Mechanical Expeller

In a mechanical expeller:

• Groundnuts are pressed using a rotating screw mechanism
• Some frictional heat is generated, but no chemicals are added
• Oil and solid cake are separated

When managed properly, this process still produces natural, unrefined groundnut oil suitable for daily cooking.

5. First Filtration – Removing Solid Particles

The fresh oil coming out of the machine contains fine particles of groundnut, known as foots. The oil is passed through:

• Cloth filters
• Mesh screens
• Primary filter units

This stage removes larger particles and gives a cleaner, smoother oil, but it may still look slightly cloudy – which is normal for natural oils.

6. Double Filtration – For Extra Clarity

To achieve double-filtered groundnut oil, the oil is passed through another round of fine filtration. This helps:

• Remove very fine suspended particles
• Improve clarity and appearance
• Increase shelf life

Importantly, this is a physical process only – no refining chemicals are used. Nutrients remain intact while the oil looks clean and bright.

7. Settling and Quality Checks

After filtration, the oil is stored in tanks for a short time to allow any remaining sediments to settle naturally. During this stage, responsible manufacturers:

• Check moisture levels
• Verify colour and clarity
• Test for any off-odour or rancidity

Only oil that passes all quality checks is moved forward for packing.

8. Filling and Packaging

The final step is packing the oil in consumer-friendly containers, such as:

• 1L, 5L or 15kg tins
• Food-grade plastic cans and bottles
• Glass bottles for premium small packs

Every pack is marked with:

• Batch number
• Packing date
• Net quantity
• FSSAI and brand details

Is the Process Chemical-Free?

In genuine natural oil mills, yes – the entire process is mechanical and physical. There is:

• No solvent extraction
• No chemical refining, bleaching or de-odorising
• No artificial colours or flavours

That is why choosing oil from a transparent, trusted brand or mill is so important.

Now that you know how groundnut oil is made, you can better appreciate the effort behind every drop of pure, natural oil that reaches your kitchen. When you choose properly made groundnut oil, you are choosing a traditional, time-tested process that respects both your health and the ingredient.