Cornflour Slurry Ratio, Crisp Frying and Cornflour vs Arrowroot
Why does the hot and sour soup from the dhaba look glossy while yours goes cloudy and gluey? Almost always it’s the cornflour slurry ratio, and when you add it. Here’s how to measure it, how to crisp chicken with it, and when arrowroot does a better job.
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Cornflour, corn starch and makai ka atta are not the same
This is the first mix-up. In Pakistan and the UK, “cornflour” on a packet means corn starch: a squeaky, bright white powder that is pure starch from maize. In the US, “corn flour” means finely ground whole maize, yellow and slightly gritty, which is closer to our makai ka atta used for makki ki roti. They don’t swap. Makai ka atta won’t thicken a soup; corn starch won’t make a roti.
Custard powder is mostly corn starch with flavour and colour, which is why it thickens milk.
The cornflour slurry ratio for every job
Starch has to be mixed with cold liquid first. Throw dry cornflour into a hot pot and each grain forms a lump with a dry centre.
| You want | Cornflour | Cold water | Per liquid |
|---|---|---|---|
| Light body, clear soup | 1 tsp | 1 tbsp | 1 cup |
| Chinese gravy, manchurian | 1 tbsp | 2 tbsp | 1 cup |
| Thick sauce, coats chicken | 1 1/2 tbsp | 3 tbsp | 1 cup |
| Set pudding, custard | 2 1/2 to 3 tbsp | 1/4 cup milk | 2 cups milk |
- Stir the cornflour into the cold water or milk in a small cup until it looks like thin milk with no dry specks. It settles within a minute, so stir again just before using.
- Bring the dish to a simmer. Starch needs heat close to boiling to thicken fully.
- Pour the slurry in a thin stream while stirring.
- Simmer for 1 to 2 minutes, stirring. It goes from cloudy to glossy and clear. Stopping earlier leaves a raw, chalky taste.
- Don’t boil hard for a long time afterwards, and don’t whisk vigorously. Long, rough cooking breaks the starch and the sauce thins out again.
Added too much? Thin it with hot stock or water a few tablespoons at a time. And if a gravy you made yesterday has turned watery overnight, that’s normal for corn starch sauces, especially with acid like vinegar or tomato. Reheat and add a small fresh slurry.
Crisping: pakoras, fried chicken and aloo
Corn starch fries up with a light, glassy crunch that wheat flour doesn’t give. That’s why restaurant recipes for chicken lollipop or crispy aloo use so much of it.
- For 500 g boneless chicken: marinate with 1 teaspoon salt, 1 teaspoon ginger garlic paste, 1 teaspoon soy sauce and 1/2 teaspoon kali mirch for 30 minutes.
- Add 1 beaten egg, 3 tablespoons cornflour and 1 tablespoon maida. Mix until every piece has a thin, sticky coat, not a thick batter.
- Heat oil to 170 to 180 °C and fry in small batches for 5 to 6 minutes until pale gold and cooked through (no pink, juices clear).
- For extra crunch, rest 5 minutes, then fry again at the hotter end for 1 minute.
For pakoras, swap 2 tablespoons of each cup of besan for cornflour. For french fries, soak cut potatoes in water 30 minutes, dry them thoroughly, toss with 1 tablespoon cornflour per 2 potatoes and fry. Oil temperature and how often you can reuse that oil are covered in our frying oil guide.
The dry-coat shortcut
Pat vegetable pieces or fish completely dry, put them in a zip bag with 2 tablespoons cornflour and your masala, shake, and tap off the excess before frying. A thin coat, and far less mess than batter.
Cornflour vs arrowroot
Arrowroot (araroot) is a starch from a tropical root; older pharmacies and pansaris sold it, and grandmothers used it for kheer and for sick-room “arrowroot biscuits”. Both thicken. They behave differently.
| Point | Cornflour | Arrowroot |
|---|---|---|
| Looks | Slightly cloudy | Very clear, glossy |
| Heat | Needs a simmer | Thickens below boiling |
| Acidic sauces | Can thin out | Holds better |
| With milk | Works well | Can turn slimy |
| Freezing | Goes spongy | Freezes better |
Swap rule: 1 tablespoon cornflour ≈ 2 teaspoons arrowroot. Add arrowroot at the very end, off the boil, and stop cooking once it’s thick, because overheating makes it thin again. Use cornflour for custard and milky desserts, arrowroot for fruit glazes and clear sweet-sour sauces.
Before packet custard, many homes set a simple firni with rice flour, and cornflour pudding arrived later as the “modern” quick version. Arrowroot was thought of as a gentle food for invalids and small children in both British-era households and some desi homes, simply because it’s bland and easy to swallow. That’s a custom of comfort, not a treatment.
Myth vs reality
Myth: cornflour is “gentle” and settles an upset stomach. Reality: it’s plain starch. Bland food can feel easier when you’re queasy, but cornflour does nothing special, and for loose motions the real priority is fluids, ideally ORS.
Myth: more cornflour in the batter means crispier food. Reality: too much gives a hard, powdery shell that falls off. A thin coat and hot oil do the work. And a sauce that looks too thin in the pot often thickens as it cools slightly, so wait a minute before adding more slurry.
Cornflour and babies
Some older advice says to thicken a baby’s milk with cornflour to “keep them full” or stop spit-up. Please don’t. Corn starch adds almost nothing a baby needs beyond calories, thickened feeds can be hard to swallow and can change how much milk a baby takes, and thickening formula should only be done with a product and method a doctor has advised. Babies under 6 months need only breast milk or formula. After 6 months, the family’s own home-cooked foods mashed soft (daal, khichdi, vegetables) are more nourishing than starch puddings. Our moong dal khichdi post is a much better first food idea.
Pure corn starch has no gluten, but factories often process wheat too, and custard or “cornflour” mixes may contain wheat, so if you have coeliac disease, buy a product labelled gluten free. Corn allergy is uncommon but real. Cornflour is almost pure starch: if you have diabetes, a cornflour-thickened soup or a bowl of custard counts as carbohydrate, so ask your diabetes educator how to fit it in. Never eat dry cornflour by the spoon; craving and eating raw starch or clay is sometimes linked with iron deficiency, so mention it to a doctor, particularly in pregnancy. Hot, thick starch sauces hold heat and stick to skin, so take extra care around children, and hold any splash burn under running tap water for 20 minutes.
Storage
Cornflour is one of the easiest pantry items to keep. Airtight jar, dry spoon, cool cupboard, and it lasts well over a year. Moisture turns it lumpy and can let mould in; a musty smell means throw it out. Keep it away from the stove’s steam, and never dip a wet spoon or a spoon that has just been in the slurry cup back into the jar. A small tin kept near the stove for daily use, refilled from the main packet, stops the whole supply going lumpy. Insects bother it far less than atta or besan.
Is cornflour the same as corn starch?
In Pakistan, India and the UK, yes. In the US, corn flour means ground whole maize, which is different.
Why did my cornflour sauce go watery?
It was boiled too long, stirred too hard, or it has a lot of acid. It also thins naturally when stored. Add a small fresh slurry and simmer 1 minute.
Can I use maida instead of cornflour?
Yes, but use about double the amount and cook a few minutes longer. The sauce will be opaque rather than glossy.
Can I give cornflour to my baby?
It isn’t needed and shouldn’t be used to thicken milk feeds unless a doctor advises it.
More pantry know-how in Desi Remedies.