Families that switched to refined sunflower oil in the 1990s and 2000s are switching back to cold pressed gingelly oil, groundnut oil and coconut oil. Not out of nostalgia, but out of a better understanding of what happened to their oil during refining — and what is preserved when you don't refine.
This article explains what cold pressing is, what it retains, and why the South Indian oils in particular are worth the switch.
1. What Happens During Cold Pressing
Cold pressing is mechanical extraction — seeds or nuts are crushed under high pressure using a rotating screw (expeller press) and the oil is squeezed out. No heat is added externally. The friction of the press does generate some heat, but temperatures are kept well below 60°C — the threshold at which most heat-sensitive nutrients start to degrade significantly.
What you get is oil that is as close as possible to what is naturally inside the seed: fat-soluble vitamins, antioxidants (tocopherols, polyphenols), phytosterols, and the full flavour and aroma profile of the original ingredient. The colour is deeper, the taste is distinct, and the shelf life (without additives) is typically 6–12 months if stored away from direct light.
2. What Happens During Refining — The Full Picture
Most mass-market cooking oils — sunflower, palm, canola, "vegetable oil" — go through a 6-to-8 step industrial process before they reach a bottle:
- Solvent extraction: Hexane (a petroleum-derived solvent) is used to extract maximum oil from the seed cake. Traces remain in the crude oil.
- Degumming: Phospholipids are removed with hot water or acid.
- Neutralisation / de-acidifying: Caustic soda removes free fatty acids.
- Bleaching: Activated clay removes colour pigments and oxidised compounds.
- Deodorising: Steam is passed through the oil at 200–270°C for 30–120 minutes to remove odour. This is the most damaging step — it destroys tocopherols (vitamin E), polyphenols and can generate trans fats.
- Winterisation / fractionation: For some oils, unwanted fats are removed by chilling and filtering.
Cold Pressed Oil
- Retains tocopherols (Vitamin E)
- Retains polyphenols & antioxidants
- No chemical solvents used
- Distinct natural flavour
- Phytosterols intact
- No deodorisation at high heat
Refined Oil
- Tocopherols largely destroyed
- Polyphenols removed in bleaching
- Hexane solvent residues possible
- Neutral / "light" odour, less flavour
- Phytosterols largely removed
- Possible trans fat formation
On trans fats: India's FSSAI has set a 2% limit on trans fats in refined oils (from 2022). The risk is not zero — high-temperature deodorisation can create small amounts, and repeated heating during cooking creates more. Cold pressed oils, not being deodorised, do not have this starting risk.
3. The South Indian Oils — Why These Specifically Matter
Gingelly Oil (Nallennai / Sesame Oil)
The most nutritionally dense of the traditional South Indian cooking oils. Cold pressed sesame oil contains sesamol and sesaminol — two powerful antioxidants that are virtually absent in refined sesame oil (they are removed or destroyed during deodorisation). Sesamol has been studied for anti-inflammatory properties. Gingelly also has a naturally balanced ratio of omega-6 to omega-9 fatty acids and a moderately high smoke point (around 175–180°C) for light sautéing. The deep amber colour and rich nuttiness of cold pressed gingelly is completely absent in its refined counterpart.
Groundnut Oil (Peanut Oil)
Cold pressed groundnut oil is dominated by oleic acid (a monounsaturated fat), making it one of the more stable plant oils for cooking. It retains resveratrol — the same antioxidant found in red wine — which is virtually eliminated in refined groundnut oil. The smell of freshly pressed groundnut oil is unmistakable: rich, roasted-nut aroma that adds flavour to tadka, curries and rice dishes. Cold pressed groundnut has a smoke point around 160–165°C, good for most Indian cooking except deep frying.
Coconut Oil
Cold pressed virgin coconut oil retains medium-chain triglycerides (MCTs) in their natural form alongside a significant polyphenol content. The key differentiator from refined coconut oil ("RBD" — refined, bleached, deodorised) is aroma and antioxidant content. Cold pressed coconut oil has the full coconut fragrance; RBD is odourless. In Kerala particularly, switching back to cold pressed coconut oil in traditional cooking has been part of a broader cultural and health reclamation. The medium-chain fatty acids are rapidly absorbed and metabolised differently from long-chain fats found in most vegetable oils.
4. The Smoke Point Question — Addressed Directly
The most common argument against cold pressed oils is smoke point. Refined oils are deodorised at 200–270°C and tend to have artificially elevated smoke points (refined sunflower oil: ~230°C). Cold pressed oils smoke earlier because they retain antioxidants, free fatty acids and moisture — these burn first.
But the question worth asking is: how much of Indian cooking actually requires temperatures above 180°C? Tadka (tempering) done in a small quantity of oil for 30–45 seconds, curry bases cooked on medium flame, stir-frying — all of these are well within the 160–175°C range where cold pressed groundnut and gingelly perform perfectly. Deep frying is the one exception; for deep frying, refined oil is practically convenient. Everything else is within range.
5. Why Ayurveda Was Right (and What That Actually Means)
Traditional Ayurvedic texts prescribed sesame oil (tila taila) as the most beneficial oil for cooking and body application — the reasoning being its stability, warmth-generating properties, and compatibility with Vata constitution. Coconut oil was prescribed for pitta (cooling properties). While we should not conflate traditional medicine with modern nutrition science, it is notable that the oils Ayurveda recommended are precisely the oils that retain the most nutrition under cold pressing — and are the ones that South Indian cuisine was built around before industrial refining arrived in the 20th century.
The returning interest in these oils is not nostalgia. It is pattern recognition: the traditional food system worked, and the generation that moved away from it is experiencing the downstream health effects of that transition.
6. Practical Switching Guide
- For tadka and tempering: Cold pressed gingelly oil or groundnut oil — both perform well at tadka temperatures.
- For curries and sabzis: Cold pressed groundnut oil is the most versatile. Gingelly adds more distinctive flavour — use it where that flavour is welcome (South Indian-style curries, rice dishes).
- For Kerala-style cooking: Cold pressed coconut oil is irreplaceable. The flavour contribution to fish curry, avial and thoran is significant.
- For deep frying: If you are committed to cold pressed only, coconut oil has the highest stability among them. Otherwise, keep a small amount of refined oil specifically for deep frying occasions.
- Storage: Store cold pressed oils in a dark glass bottle away from direct sunlight. Gingelly and groundnut keep well at room temperature for 6 months; coconut may solidify below 24°C — this is normal and does not affect quality.
7. Press Your Own at Home
The freshest cold pressed oil you can use is oil you press yourself, the same day. A Hakura Comfort or Classic oil press machine lets you press 8–15 kg of seeds per day at home, giving you oil with maximum nutrient retention — nothing has been stored, heated in transit, or exposed to light for weeks. Many health-conscious households in Tamil Nadu and Kerala now buy seeds in 5–10 kg lots and press fresh oil every 2–3 weeks.
See the Hakura home oil press machines →
Press fresh oil at home
The Hakura Comfort and Classic machines press groundnut, sesame and coconut at home — fresh oil in under an hour.