Refined oil is edible oil that has been extracted, often with a solvent such as hexane, and then degummed, neutralised, bleached and deodorised until it is pale, odourless and long-lasting. Those steps remove colour, smell and many natural plant compounds. Unrefined oil, such as wood-pressed kachi ghani oil, is simply pressed and filtered.
Last updated: 6 Oct 2026 | Shop cold pressed groundnut oil
Walk down any supermarket oil aisle in India and most of what you see is refined. The bottle may say sunflower oil, soybean oil, rice bran oil, palm oil or simply “vegetable oil”, and in most cases the oil inside has been through an industrial refining line. This guide explains what that means in plain terms: what refined oil is, how it is made, what the process changes, and when an unrefined oil is the better fit for your kitchen.
We press unrefined oil for a living, so we have a point of view. We have tried to stick to what is well established and to say clearly where refined oil is a reasonable choice.
What is refined oil, exactly?
Refined oil is the finished product of a multi-stage industrial process. Crude oil, whether pressed hot or dissolved out of the seed with a solvent, is cleaned up in a refinery until it meets a standard of appearance, taste and shelf life. The aim is consistency: a refined sunflower oil from one batch should look and taste like the next, which is exactly what large brands and restaurant kitchens need.
Soybean, sunflower, rice bran, palm, cottonseed and canola oils are almost always sold refined, and refined versions of groundnut, sesame and mustard oil exist too. On a label, look for words such as “refined”, “physically refined”, “double refined” or the generic “edible vegetable oil”. “Filtered” and “double filtered” do not mean the same thing: filtering only removes particles, while refining changes the oil itself.
How refined oil is made, step by step
Plants differ in the details, but the sequence is broadly the same:
- Extraction. Seeds are crushed, and in many large plants the remaining oil is dissolved out of the seed cake with hexane, a petroleum-derived solvent, to raise the yield. The solvent is then evaporated and recovered.
- Degumming. Water or acid is used to remove gums, mainly phospholipids, which would otherwise make the oil cloudy and shorten its life.
- Neutralising. An alkali such as caustic soda removes free fatty acids, which cause bitterness and rancidity. The resulting soapstock is separated out.
- Bleaching. The oil is passed through activated clay (bleaching earth) that adsorbs pigments such as carotenoids and chlorophyll, leaving it pale.
- Deodorising. Steam is passed through the oil at very high temperature, usually under vacuum, to strip away the volatile compounds that give smell and flavour.
- Optional steps. Some oils are also winterised so they stay clear in the cold, and some have antioxidants added to extend shelf life. Indian food regulations permit certain approved antioxidants within set limits; on labels they appear as INS numbers such as 319, 320 or 321.
Hexane is largely removed during processing, and food regulators set limits on what may remain. For a home cook the more useful point is not that refined oil is “toxic”. It is that the process is designed to remove almost everything that made the oil smell and taste like its seed.
What refining changes in the oil
Refining does several things well. It removes impurities that spoil oil, gives a neutral taste, and raises the temperature at which the oil begins to smoke, which is why refined oils dominate deep frying. It also comes with trade-offs:
- Natural compounds are reduced. Bleaching and deodorising lower the pigments and aroma compounds, and some of the vitamin E (tocopherols) and plant sterols the seed originally carried. How much is lost varies by oil and by plant.
- Flavour disappears. That is by design. A refined groundnut oil tastes of very little, while an unrefined one smells clearly of roasted nuts.
- Trace trans fats can form. Prolonged high-temperature deodorising can create small amounts of trans fatty acids. Partially hydrogenated fats such as vanaspati are a different and larger concern. FSSAI caps industrial trans fat in oils and fats at 2 per cent of total fat.
- The basic fat mix does not change. Refining does not turn a polyunsaturated oil into a monounsaturated one. A refined oil has the same broad fat profile as the pressed oil from that seed; the difference lies in the minor components and in the processing history.
Refined vs unrefined oil at a glance
| Feature | Refined oil | Unrefined oil (wood-pressed / kachi ghani) |
|---|---|---|
| Extraction | Often solvent (hexane) after pressing, at scale | Mechanical pressing only |
| After extraction | Degumming, neutralising, bleaching, deodorising | Filtering and resting |
| Colour and smell | Pale and near-odourless | Natural colour with a clear aroma of the seed |
| Taste in food | Neutral | Noticeable; adds character to the dish |
| Natural compounds | Reduced by the refining steps | Largely retained |
| Smoke point | Generally higher | Generally lower |
| Shelf life | Longest | Shorter; use within the labelled date |
| Batch consistency | Very uniform | Some natural variation between batches |
| Typical use | Deep frying at scale, neutral-taste cooking | Everyday Indian cooking, tempering, shallow frying, finishing |
When refined oil is a reasonable choice
Refined oil is not illegal, adulterated or unsafe by definition. It is the standard cooking oil in a large part of the country, and it is regulated. If you deep fry in large volume, want a flavour-neutral oil for baking or certain sweets, or buy mainly for shelf life, refined oil does that job. What we would question is marketing that presents a refined oil as “light”, “heart friendly” or “natural” while saying nothing about how it is made.
Two habits matter more than the word on the bottle: do not reuse frying oil again and again, and do not leave any oil smoking on the heat. Both apply equally to refined and unrefined oils.
How to read an oil label
- “Refined”, “double refined”, “physically refined” and “edible vegetable oil” all point to a refined product.
- “Cold pressed”, “wood pressed”, “lakdi ghani” and “kachi ghani” describe pressing, not refining. They are not tightly regulated claims, so find out who actually presses the oil and where.
- An ingredients line mentioning INS 319, 320 or 321 means a synthetic antioxidant (TBHQ, BHA or BHT) has been added.
- Vague wording such as “pure” or “natural” tells you nothing about the process. Our guide to testing cold pressed oil at home lists simple checks you can run yourself.
What to use instead: wood-pressed (kachi ghani) oil
Unrefined oil skips the refinery. At our mill in Hudkeshwar, Nagpur, seeds go into a wooden ghani (kolhu) that turns slowly, so friction heat stays low. The oil is then filtered, rested and bottled at the same site: no hexane, no bleaching, no deodorising, nothing added. You can see each step on our Nagpur oil mill page.
You will notice the difference in the kitchen. Our groundnut oil has a faint golden colour and a nutty aroma, and that carries into tadka, sabzi and shallow frying. Cold pressed groundnut oil is the easiest place to start because it works across everyday Indian cooking.
A simple way to switch
- Start with one oil. Replace the oil you use most rather than changing everything at once.
- Expect a stronger aroma for the first few meals. Most people find it settles as they adjust their recipes.
- Buy a pack you will finish. Unrefined oil has a shorter shelf life, so match the size to how fast you cook. Our guide to how much oil a family of four needs helps with the arithmetic.
- Store it well. Keep it away from light and heat, cap closed, and use it within the date on the bottle.
- Keep a neutral oil for big fry-ups if you cook for large gatherings. Many families run a pressed oil for daily cooking and a refined one for occasional deep frying.
Keep reading
For the processing in more detail, see what the refining steps involve and what to look for on labels. For a side-by-side view, read cold pressed vs refined oil or the complete guide to wood-pressed, cold-pressed, kachi ghani and refined oil. If you want help choosing an oil for a specific dish, start with our guide to cooking oils for Indian cooking.
Frequently asked questions
What is refined oil in simple words?
Refined oil is cooking oil that has been industrially cleaned after extraction. It is degummed, neutralised with alkali, bleached with clay and steam-deodorised until it is pale, odourless and neutral in taste. The result is a consistent oil that lasts a long time but has lost most of its natural colour, aroma and many minor plant compounds.
Is refined oil the same as filtered oil?
No. Filtering only strains out particles and sediment, so a filtered oil can still be completely unrefined. Refining changes the oil itself through heat and chemical treatment. A bottle labelled “double filtered” does not tell you whether it is refined, so look for the word “refined” or ask the producer how the oil is made.
Which oils are usually sold refined in India?
Soybean, sunflower, rice bran, palm, cottonseed and canola oils are almost always sold refined, and refined groundnut, sesame and mustard oils also exist. Traditional oils such as groundnut, sesame, mustard, coconut and flax are also sold unrefined, pressed in a wooden ghani or a steel expeller. The label should state which one you are buying.
Is refined oil safe to eat?
Refined oil sold in India must meet FSSAI standards, including limits on residual solvent and industrial trans fat, so it is legal and widely eaten. The case for unrefined oil is not that refined oil is poison, but that refining strips out natural compounds and flavour. Avoid overheating or repeatedly reusing any oil.
Does refined oil have a higher smoke point than unrefined oil?
Generally yes. Removing free fatty acids and other impurities raises the temperature at which refined oil begins to smoke, which is why it dominates deep frying. Unrefined oils smoke at lower temperatures, so they suit tempering, sautéing and shallow frying better. Whichever oil you use, do not leave it smoking on the heat.
Can I use cold pressed oil for everyday Indian cooking?
Yes. Cold pressed groundnut, sesame and mustard oils are traditional choices for tadka, sabzi, curries and shallow frying. Heat groundnut and sesame oil gently until it shimmers. Mustard oil is traditionally warmed until it just begins to smoke, then cooled, to mellow its sharpness. For repeated deep frying in quantity, a more heat-stable oil is more practical.
Written by Dushyant Waghmare, founder — Parampara Naturals, who operates a wooden ghani oil mill in Nagpur.
Last updated: 6 Oct 2026