Oiling Pan: Before Or After Preheating?

There are differing opinions on whether you should oil a pan before or after preheating it. Some sources suggest that adding oil to a hot pan prevents food from sticking, while others argue that it doesn't make a difference. Proponents of adding oil to a hot pan claim that it gives a more even coating, prevents the oil from breaking down and forming a gummy substance, and provides a warning sign if the pan gets too hot. On the other hand, those who prefer to add oil before preheating believe that it gives the oil less time to burn and that a hot pan is necessary for cooking regardless of when the oil is added. Ultimately, the decision may depend on the type of pan and the temperature required for cooking.

Non-stick pans: add oil first to avoid damage

Non-stick pans are convenient for cooking sticky foods like eggs, pancakes, seafood, and rice. However, there are some best practices to follow to ensure you don't ruin your non-stick pan. One of the most important things to remember is to add oil to the pan before heating it up.

Adding oil to a non-stick pan first may seem counterintuitive, but it serves an important purpose. The oil enhances the non-stick effect of the pan, and more importantly, it acts as a lubricant to prevent the pan from emitting potentially unhealthy fumes. By adding the oil first, you allow it to heat up gradually along with the pan, reducing the risk of burning or breaking down the oil.

It's worth noting that non-stick pans should not be preheated without any oil or food inside, as high dry heat can cause deterioration of the non-stick coating. Always add a small amount of oil to the pan before turning on the heat. Suitable oils include canola, olive, vegetable, or corn oil. Butter can also be used.

Additionally, it's crucial to use the right utensils with non-stick pans. Avoid using metal utensils as they can scratch and scrape the non-stick surface. Instead, opt for wooden spoons, heatproof silicone spoons, and spatulas.

By following these simple guidelines, you can extend the lifespan of your non-stick pan and enjoy the benefits of easy cooking and cleanup.

Stainless steel pans: heat first to avoid food sticking

Food sticks to stainless steel pans because of their porous surface. The pores expand and contract with heat, and when cold food is added, the pores relax, causing the food to get stuck.

How to avoid food sticking to stainless steel pans:

Firstly, it is recommended to preheat the pan. Place the pan on the stove, turn the stove to medium heat, and allow the pan to preheat for 2-3 minutes. The ideal temperature is between 225°F and 235°F.

You can test if the pan is at the right temperature by using the water droplet test. Add a teaspoon of water to the pan. If the water forms a large, marble-like drop that bounces off the sides of the pan, it is ready. If the water fizzles and foams, the pan is too cold. If the water breaks into many small beads and evaporates, it is too hot.

Once the pan is preheated, add oil or fat and ensure it covers the surface entirely. If using a high-heat culinary thermometer, the ideal temperature for frying is between 160°C and 180°C.

When the oil is hot enough, it will glisten, shimmer, and spread around the pan. To test this, bring a small portion of your ingredient to the surface of the pan. If it sizzles immediately, the pan is ready.

Additional tips to avoid food sticking:

• Bring ingredients to room temperature before adding them to the pan.
• Once your ingredients are sizzling, leave them for a couple of minutes before flipping or moving them.
• Do not overcrowd the pan, as this will drop the temperature and cause food to steam rather than sear.
• Use dry ingredients instead of wet ingredients.
• Do not move the food around too often. Allow it to cook and develop a steam layer or brown crust that will release it from the pan.
• Ensure proper care of your stainless steel pan. Do not wash a hot pan with water. Instead, let it cool down and then rinse with hot water and soap.

Wok searing: add oil last to avoid a smoking mess

When wok searing, it is best to add the oil to the wok after preheating it. This is because woks are usually heated to very high temperatures, and oils have a smoke point—a temperature at which they begin to smoke and decompose.

Preheating a wok

A well-seasoned and properly cleaned wok will have micropores in the metal that hold some oil or food particles. When preheating a wok, it will begin to smoke, releasing the flavour stored in the wok before you add the oil.

The importance of oil smoke points

Most neutral oils have a smoke point above 200°C (around 400°F), which is well above the temperature required for most cooking tasks. However, oils like sesame oil, olive oil, and soybean oil have lower smoke points and will burn at high temperatures, so they are not suitable for wok cooking.

Wok hei

To achieve wok hei, the signature smoky dragon's breath flavour of good wok cookery, it is essential to have a hot wok and a spare cooking environment. Adding oil to a hot wok will result in a smoking mess, so it is best to add the oil and ingredients in quick succession to minimise the time the oil has to burn.

Pan-frying: add oil to a cold pan to avoid a burn risk

There are conflicting opinions on whether to heat a pan before adding oil. Some sources suggest that adding oil to a hot pan prevents food from sticking, while others claim that adding oil to a cold pan is safer and just as effective.

The case for adding oil to a hot pan

Some cooks prefer to add oil to a hot pan because they believe it prevents food from sticking. This is because a hot pan will heat the oil instantly, and a hot pan with hot oil is less likely to cause sticking than a cold pan.

The case for adding oil to a cold pan

Adding oil to a cold pan is safer because oil can burn and smoke if added to a hot pan, especially if the pan is empty when heated. Oil has a smoke point, which is the temperature at which it starts to smoke and decompose. If a pan is heated beyond the smoke point of the oil, the oil will burn when added.

Adding oil to a cold pan also allows the cook to use the oil as a temperature gauge. They can add the food to the pan when the oil becomes runny or starts to shimmer, indicating that the pan is at the right temperature.

Exceptions

There are some exceptions where it is necessary to heat the pan before adding oil. For example, when searing meat or cooking in a wok at high temperatures, the pan needs to be hot before oil is added, otherwise, the oil will smoke and burn before the food can be added.

Adding oil to a cold pan is generally safer and just as effective at preventing food from sticking as adding oil to a hot pan. However, there are some exceptions where it is necessary to heat the pan first. Ultimately, it is a matter of personal preference, as long as the oil is not heated above its smoke point.

Sweating vegetables: no benefit to preheating

When it comes to sweating vegetables, there's no need to preheat the pan. This technique involves cooking vegetables at a gentle heat to soften them and draw out their flavours. It's often used as a preliminary step in longer cooking methods, such as braises and soups, where the vegetables will continue to cook for an extended period.

The goal when sweating vegetables is to avoid browning, so keeping the heat relatively low is important. This means that preheating the pan is unnecessary, as you'll want to add the vegetables to the pan as soon as it reaches the desired temperature.

To sweat vegetables successfully, start by heating a small amount of oil in a pan over medium-low heat. Add your chopped vegetables and a pinch of salt, stirring to coat them in the oil. Adjust the heat to maintain a gentle sizzle, and stir frequently to prevent browning. Once the vegetables are softened and translucent, you're ready to move on to the next step in your recipe.

So, while preheating the pan may be beneficial for certain cooking techniques, such as searing meat or wok frying, it's not necessary when sweating vegetables. In this case, it's more important to control the temperature carefully to avoid overheating the vegetables.

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