A lot of curry recipes have instructions for frying some of the ingredients. Most curries would be pretty tasteless if they didn’t include fried onions or spices and deep fried prawn pakoras or beef koftas wouldn’t exist without deep fat frying.
So just how do you know when the cooking oil is hot enough to use? It isn’t any good just looking at the oil – if it is smoking then it is too hot – you should not cook in smoking oil at all.
A lot of recipes say “heat the oil over a medium heat” or “heat the oil over a medium to high heat”. But people’s cookers/stoves heat at different rates and the thickness of saucepans and frying pans, as well as the different amount of oil used, means that the oil heats at different speeds for different people.
We’ve searched the internet for the most obvious tips for you.
The obvious thing to use to test the oil temperature is a thermometer. A thermometer is probably the best method. You just put it into the oil and keep checking until the temperature gets to the level that you want.
But there are problems with using a thermometer. First of all, most recipes don’t say to which temperature you should heat the oil. Next, a thermometer is best used when you are deep frying – it’s going to be difficult to measure the temperature of a couple of tablespoons of oil in a large frying pan and you’ll probably end up measuring the temperature of the metal of the frying pan, rather than the oil.
Here’s the first tip. Most deep fat frying takes place when the oil temperature is around 188C (370F). So if you’ve got a thermometer to use then at least you now know what temperature to aim for.
Of course, not everyone has a thermometer and some thermometers don’t even go up to 188C (370F).
One tried and trusted way of testing the oil temperature is to check with the handle of a wooden spoon (or even using a wooden chopstick). If you dip the end of the handle into the oil, the oil is hot enough when bubbles of oil freely form around the handle. And this technique apparently works for testing the oil temperature in frying pans (or saucepans) as well as for oil being used for deep fat frying.
Another test is to drop an unpopped popcorn kernel into the oil. The popcorn kernel will pop when the temperature gets between 176C (350F) and 185C (365F). The internet postings that discuss this method say that the popping corn will not spray you with hot oil.
And yet another test for deep fat frying is to drop a small cube (about 1/2 cm or 1/4 inch) of bread into the oil when you think it’s hot enough. If the bread comes back up to the surface crackling and frying then the oil is hot enough.
A favourite among many for checking the oil in a frying pan (or saucepan) is to flick a drop of water into the oil. If the drop of water splutters as soon as it is flicked into the oil, then the oil is hot enough. Obviously you need to be careful not to flick too much water into the oil – a single drop is enough and I’ve never had any problems using this method.
If you’re still not sure, put in a small amount of food you’re going to be frying and wait for it to start frying before you add the rest of the ingredient.
The general tips that people give out include “heat the pan before adding the oil – don’t heat the pan and oil from cold at the same time”, “don’t overheat the oil – smoking oil is bad, bad, bad”, “be very careful and treat hot oil with respect – being burnt with hot oil is painful and can give you horrific burns” and “never let a child cook using hot oil – ever”.
You can use whatever method you want to test to see if the oil is hot enough to use and with experimentation you’ll find the best method for you.