For most Indian deep frying, groundnut oil is the most dependable everyday choice. It copes with the long, hot sessions that pakoras, puris, vadas and murukku need; its mild flavour suits almost every snack, and it has been the frying oil of Gujarat, Maharashtra, Andhra Pradesh and Tamil Nadu for generations. Mustard oil and gingelly oil are excellent when you want their flavour in the food, and coconut oil works well for Kerala-style chips and shorter frying jobs. Oils very high in polyunsaturated fat, such as regular sunflower oil, are better kept for lighter cooking.
The rest of this guide explains why, and how to match the oil to what you are frying.
What deep frying asks of an oil
Finding oil for deep frying is the hardest job. A kadhai sits at roughly 170°C to 190°C for twenty minutes or more; food releases water into it, batter crumbs fall to the bottom, and air keeps reaching the surface. Under that stress, oils break down. They oxidise, darken, foam, thicken, and start to smell.
Two properties decide how well an oil copes.
Fatty acid makeup. Saturated and monounsaturated fats are chemically steadier under heat. Polyunsaturated fats have more points in their structure where oxygen can attack, so oils rich in them break down faster when held hot for a long time. Groundnut oil is rich in monounsaturated fat, coconut oil is mostly saturated, and regular sunflower oil is dominated by polyunsaturated fat.
Smoke point. This is the temperature at which an oil visibly smokes. It matters, though it gets more attention than it deserves. An oil can sit below its smoke point and still oxidise steadily through a long frying session, so stability over time is the more useful question for deep frying. If you want the numbers for common oils, our guide to smoke points of cooking oils in India lists them.
How each oil behaves in the kadhai
Groundnut oil
Groundnut oil is the all-rounder. Its high monounsaturated content gives it staying power, and its gentle flavour does not fight with besan, rava, maida or rice flour batters. Cold-pressed groundnut oil carries a fuller, nutty aroma than refined versions, which many families enjoy in bhajji, bonda and sabudana vada. If you fry several times a week, this is the oil to keep in a larger pack. Our cold pressed groundnut oil comes in sizes from small bottles to family cans.
Mustard oil
In Bengal, Bihar, Odisha, Punjab and much of North India, mustard oil is the frying oil. Its sharp, pungent warmth suits fish fry, aloo pakora, luchi and Bengali beguni. Mustard oil is high in monounsaturated fat and also carries some omega-3, which is unusual among frying oils. Traditional cooks heat it until it just begins to smoke before adding food, which mellows the raw pungency. If your family dislikes the mustard bite, they will taste it in every snack, so pick it when you want that flavour.
Gingelly (sesame) oil
Gingelly oil has a mix of monounsaturated and polyunsaturated fat, along with natural compounds such as sesamol and sesamin that help it resist oxidation better than its fatty acid profile alone would suggest. Tamil Nadu and Karnataka kitchens use it for murukku, seedai and thattai, where its toasted note is part of the recipe. It usually costs more than groundnut oil, so many homes reserve it for festive snacks. See our cold pressed gingelly oil if you make these often.
Coconut oil
Coconut oil is around 90 percent saturated fat, which makes it very stable. Cold pressed coconut oil has a lower smoke point than refined coconut oil and a strong coconut aroma. It is the classic oil for Kerala banana chips, jackfruit chips and many fish fries, and it suits moderate heat better than long, very hot sessions. It turns solid below about 24°C, so in winter you may need to warm the bottle before pouring.
Sunflower oil
Regular sunflower oil is high in linoleic acid, a polyunsaturated fat. It does a fine job for quick shallow frying and everyday sabzi, and it is the least suited of these oils to long or repeated deep frying. If sunflower is your family’s preferred taste, fry in smaller batches and avoid reusing the oil.
A dish-by-dish guide
| What you are frying | Oil that suits it best | Why |
|---|---|---|
| Pakoras, bhajji, bonda | Groundnut or mustard | Stable through long batches; mustard adds North and East Indian flavour |
| Puri, luchi, bhatura | Groundnut; mustard for luchi in Bengal | Clean taste, good heat tolerance |
| Medu vada, masala vada | Groundnut | Thick batter needs long, steady frying |
| Murukku, thattai, seedai | Gingelly or groundnut | Traditional flavour, good stability |
| Banana and jackfruit chips | Coconut | Classic Kerala flavour, very stable fat |
| Fish fry | Mustard (East), coconut (Kerala), groundnut (elsewhere) | Regional taste |
| Samosa, kachori | Groundnut | Low, slow frying for a flaky crust |
| Cutlets, quick shallow fry | Any of these, including sunflower | Short heat exposure |
Checking oil temperature without a thermometer
Drop a small piece of batter into the oil. If it sinks and stays at the bottom, the oil is too cool and the food will soak up oil. If it sinks briefly and then rises steadily with bubbles around it, the oil is ready. If it rises instantly and browns within seconds, the oil is too hot, and the outside will darken before the inside cooks.
A wooden spoon handle dipped into the oil gives a similar signal. A steady stream of small bubbles means you are in the frying range.
Heavy smoke means the oil is breaking down, and it fills the kitchen with irritating fumes. Mustard oil is the one exception where a brief first smoke is part of tradition. Lower the flame as soon as it appears.
Habits that matter as much as the oil
- Fry in batches. Overloading the kadhai drops the temperature and makes food greasy.
- Skim crumbs often. Burnt particles speed up breakdown.
- Use a heavy kadhai. Iron or thick steel holds heat steadily.
- Avoid endlessly topping up old oil with fresh oil. The old oil drags the fresh oil down with it.
- Limit reuse. FSSAI’s household guidance says frying oil can be filtered and used for curries within a day or two, and should be discarded once it turns dark, thick or foamy. Our guide on reusing cooking oil after frying walks through it.
For safety steps such as keeping water away from hot oil and handling flare-ups, read our guide on how to deep fry safely.
Where fried food fits in everyday eating
Fried snacks are part of Indian food culture, and quantity matters most. The ICMR-NIN Dietary Guidelines for Indians (2024) recommend using oils in moderation and rotating between different oils over time. Picking a stable oil, frying at the right temperature and avoiding repeatedly reheated oil all help, and so does keeping fried food an occasional treat. For daily cooking choices, our guide to the best oils for Indian cooking compares the common options.
Frequently asked questions
Which oil is best for frying pakoras at home?
Groundnut oil is the most reliable choice because it stays stable through several batches and has a mild taste. Mustard oil is the traditional pick in North and East India if you want its pungent flavour.
Can I deep fry in cold-pressed oil?
Yes. Cold-pressed groundnut, mustard, gingelly and coconut oils have been used for frying in Indian homes for centuries. Keep the flame moderate, fry in batches and avoid letting the oil smoke heavily.
Is sunflower oil good for deep frying?
Regular sunflower oil is high in polyunsaturated fat, which breaks down faster during long frying. It suits quick, lighter cooking better. If you do fry with it, avoid reusing it.
Why does my oil foam while frying?
Some foaming is normal when wet food enters hot oil. Thick foam that will not settle usually means the oil has been heated too long or reused too often, and it is time to discard it.
When should I throw away frying oil?
Discard it when it turns dark and murky, thickens, smells sharp or stale, smokes at normal frying heat, or forms foam that will not settle. These are the same signs listed in FSSAI’s guidance on used cooking oil.
