The Science Behind Cold Pressing: How Nutrients Are Preserved?

science behind cold pressing

For decades, refined oil was the default in every Indian kitchen. It was cheap, widely available, and backed by large brands with larger advertising budgets. Then came the red flags. 

Studies began pointing to stripped nutrients, chemical solvent residues, and processing temperatures that cross 200°C. Cold pressed oil stepped in as the alternative, and with it came a question most buyers are quietly asking: is this a genuine nutritional upgrade, or just a marketing gimmick?

The science is clear. Refining destroys up to 90% of Vitamin E. Cold pressing keeps oil below 50°C with no chemicals. That temperature gap is where nutrition either survives or disappears.

At Nayesha Oil Mills, every batch of cold pressed oil is pressed below 50°C in wooden Ghani machines and lab-tested before it leaves. This blog explains what the science behind cold pressed oils actually preserves, and why it matters.

What Nutrients Are Preserved in Cold Pressing?

Cold pressing preserves four things that refining removes: Vitamin E, healthy fats (MUFA), polyphenols, and natural flavour compounds. Each one does a different job in the body.

  1. Vitamin E is a fat-soluble antioxidant. That means it dissolves in fat and protects cells from damage. Nayesha's cold-pressed groundnut oil retains 15.7mg of Vitamin E per 100g. Refined groundnut oil retains 1.5 to 2mg. 

  2. MUFA stands for monounsaturated fatty acids. It is the healthy fats found at 46% concentration in groundnut oil. These fats help cells respond to insulin and support heart health. Cold pressed oil online keeps MUFA intact.

  3. Polyphenols are natural anti-inflammatory compounds found in the seed. It breaks down above 40°C. Cold pressing, at below 50°C, keeps them intact. 

  4. Natural Flavour Compounds, when cold pressed oil smells and tastes like the seed it came from, that's a sign the bioactive profile is intact. Refining strips these out in the deodorisation stage.

Milan and Vesna (2023), ScienceDirect, found that cold pressed oils retain significantly more bioactive compounds than refined oils.

How Are Nutrients Preserved in Cold-Pressed Oil? 5 Reasons the Process Works

The nutrients survive because of five specific things the cold pressing process does. The absence of heat, chemicals, and multiple processing stages is what makes the difference, not just the temperature setting.

1. Temperature Stays Below 50°C

Vitamin E begins degrading above 60°C. Polyphenols start breaking down above 40°C. The 50°C threshold sits inside the safe window for both.

The deodorisation stage in refined oil reaches 200°C+. At that temperature, most of the oil's natural compounds are already gone. 

2. No Chemical Solvents Used

Refined oil production uses hexane (a petroleum-derived chemical solvent) to extract oil from seeds. Hexane pulls more oil out per kilogram of seed. But it leaves residue that has to be removed in a separate stage later.

Cold pressing uses only mechanical pressure. No hexane. No solvent residue. The Journal of the American Oil Chemists' Society (2017) confirmed that chemical solvent refining destroys most natural vitamins, fatty acids, and phenols.

3. Mechanical Press Only

Cold pressing uses a physical press: a wooden churner in the Kacchi Ghani method. It squeezes oil from seeds using slow friction and gravity.

Slow pressing generates almost no heat. The slower the press, the lower the temperature, thus answering how nutrients are preserved.

The high-speed mechanical presses used in refining generate significant heat before the hexane stage even begins.

4. Single Press, Not Multiple

The best cold pressed oil is extracted in one press. What comes out is filtered and bottled.

Oil in the refining process goes through multiple extraction stages to squeeze out every last drop. Each stage adds pressure, heat, and processing time. Each stage strips more nutrients. A higher yield per seed means lower nutrients per litre.

5. No Bleaching or Deodorisation

Refining has six stages after the initial extraction:

  • Hexane extraction

  • Degumming (removes phospholipids)

  • Neutralisation (removes free fatty acids with sodium hydroxide)

  • Bleaching (removes colour and contaminants)

  • Deodorisation: removes smell at 200°C+ (the most destructive stage)

  • Additives (synthetic stabilisers added back)

Each stage removes something natural. Nayesha Oil Mills cold pressed oil skips all six. The oil from the seed is the oil in the bottle. To buy cold pressed oil, call Nayesha Oil Mills.

Order Best Cold Pressed Oil from Nayesha Mills Today! 

The science only works if the process actually follows it. The best cold pressed oil is the one where the producer can show you the extraction temperature, the batch number, and the FSSAI certification. 

At Nayesha Oil Mills, every bottle carries:

  • Extraction temperature (below 50°C)

  • FSSAI licence number

  • Batch code and pressing date

Our Kacchi Ghani wooden churner presses slowly, generates minimal heat, and produces less oil per kilogram of seed than a high-speed press. We press in small batches because larger batches generate more heat. Cold pressed oil price varies by pack size. The 5L cold pressed oil online gives the best per-litre value for daily family cooking.

To buy cold pressed oil, call Nayesha Oil Mills at +91 73004 83669 and order directly.

Frequently Asked Questions

What Nutrients Are Preserved in Cold Pressed Oil? 

Vitamin E, monounsaturated fatty acids (MUFA), polyphenols including resveratrol, and natural flavour compounds. These survive because cold pressing keeps the oil below 50°C with no chemical solvents or bleaching stages. Refining removes most of these through heat and chemical processing.

Why Does Cold Pressing Happen Below 50°C? 

Because Vitamin E starts degrading above 60°C and polyphenols break down above 40°C. The 50°C limit keeps it inside the safe preservation window. That's why it's the standard. Refining reaches 200°C+ in the deodorisation stage, which destroys both.

What Does Refining Do to Cooking Oil? 

Refining has six stages: hexane solvent extraction, degumming, neutralisation, bleaching, deodorisation at 200°C+, and adding synthetic stabilisers. Each stage removes something natural from the oil. By the end, the oil is stable and odourless but nutritionally depleted.

Is Cold Pressed Oil Better for Everyday Indian Cooking? 

Yes, for medium-heat cooking: tadka, sautéing, light frying. Cold pressed oil's smoke point handles everyday Indian cooking without breaking down. Deep frying daily at very high temperatures is better with refined oil for stability. For regular home cooking, cold pressed oil gives you both usability and nutrition.

How Do I Know if an Oil Was Genuinely Cold Pressed? 

When you want to buy cold pressed oil, check three things: an FSSAI licence number (not just the logo), the extraction temperature stated on the label (should say below 50°C), and a batch number. A cold pressed oil without these three hasn't proven its process. Nayesha carries all three on every bottle.

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