Frying Fish: How Long Should You Deep Fry?

Frying fish in a deep fryer is a delicious and quick way to cook fish of any kind. The crispy crust formed when fried in hot oil is a treat for all the senses. There are a few things to keep in mind when frying fish in a deep fryer to ensure the best results. Firstly, the type of oil used is important; neutral oils like corn, canola, or sunflower oil are ideal as you want to taste the food, not the oil. Secondly, temperature control is crucial; the oil should be heated between 350 and 375 degrees Fahrenheit. Too low and the food will be greasy, too high and it will burn. Lastly, the batter plays a key role in achieving the perfect crispy texture; a raising agent like baking powder or yeast, or a carbonated liquid like beer or sparkling water, will give the batter a light and crisp texture.

Characteristics of Frying Fish in a Deep Fryer

Oil temperature

The ideal temperature range for frying fish is between 350 and 375 degrees Fahrenheit (180 to 190 degrees Celsius). Heating the oil to this temperature range ensures that the fish cooks evenly and results in a crispy, golden-brown crust. If the oil is too cold, the fish will absorb too much oil and become greasy. On the other hand, if the oil is too hot, the fish will burn and the crust will be uneven.

It is important to use a thermometer to monitor the oil temperature and adjust the heat source as needed. A deep-fry or candy thermometer can be used to accurately measure the temperature of the oil. The thermometer should be placed in the oil before heating to ensure an accurate reading.

When frying fish in a deep fryer, it is also essential to fry in batches. Adding too much fish to the hot oil at once will cause the oil temperature to drop. This can result in uneven cooking and a less-than-desirable crust. By frying in smaller batches, you can maintain the optimal oil temperature and ensure that each piece of fish is cooked perfectly.

Additionally, the size and thickness of the fish fillets can impact the frying time and temperature. Thicker fillets may require slightly lower temperatures and longer cooking times to ensure that the fish is cooked through. It is important to monitor the fish closely and adjust the temperature or cooking time as needed to achieve the desired result.

Oil type

When deep-frying fish, it is important to use an oil with a high smoke point of 400° F or higher. This is because deep-frying is done at high temperatures, usually between 350 and 375 °F. Oils with a high smoke point include peanut oil, vegetable oil, grapeseed oil, canola oil, safflower oil, rice bran oil, sunflower oil, and coconut oil.

Vegetable oil is the most common and affordable option. It has a smoke point of 450° F, but it doesn't prevent flavour transfer. Peanut oil is also affordable and has the same smoke point, but it does prevent flavour transfer. Canola oil is another good option, with a smoke point of 400° F. It is flavourless and rich in omega-3 and omega-6 fatty acids, which are beneficial for heart health. Coconut oil has the same smoke point as canola oil and is flavourless, but it is a more expensive option.

It is also important to fill your vessel with no more than two-thirds of oil. You only want enough to submerge your food.

Fish preparation

Choosing a fish

The type of fish you choose is up to you, but popular options for frying include cod, haddock, sea bass, tilapia, pollock, walleye, whitefish, and orange roughy.

Preparing the fish

Pat the fish fillets dry with kitchen paper. This is important because any excess water will cause the oil to splatter.

Preparing the batter

There are several options for batter. A basic batter can be made by mixing flour, salt, baking powder, and dill. You can then add beer, milk, and eggs. Alternatively, you can use cornflour, plain flour, fine sea salt, real ale, and white wine vinegar. For a lighter batter, you can add a raising agent such as baking powder or yeast, or use a carbonated liquid like sparkling water or beer.

Place the fish fillets in the batter mixture and coat them well. Let the fish stand in the batter for around 15 minutes.

Preparing the fryer

Fill your deep fryer halfway with vegetable oil, peanut oil, corn oil, or sunflower oil. Heat the oil to a temperature between 350 and 375 degrees Fahrenheit.

Frying the fish

Carefully place the battered fish into the hot oil, being careful not to splash. Fry the fish in batches to maintain the oil temperature. Fry for around 4 to 6 minutes, depending on the size and thickness of the fillets. The fish is done when it is golden brown and crispy.

Remove the fish from the oil using a slotted spoon or tongs and place it on a plate lined with kitchen paper to absorb any excess oil. Serve immediately.

Batter consistency

The consistency of the batter is crucial to achieving the perfect fried fish. The ideal batter should be smooth, with a consistency similar to double cream. It should be thick enough to coat the fish evenly and create a protective layer that seals in the moisture and flavour of the fish. Here are some tips to achieve the perfect batter consistency:

• Use a combination of flours: A mixture of plain flour and cornflour or cornstarch will give your batter the right texture and crispiness. The ratio of cornflour to plain flour can be adjusted to your preference, but a common ratio is 1:3.
• Add liquid gradually: The liquid component of the batter, such as water, beer, or milk, should be added gradually and whisked until smooth. This will help you control the consistency and avoid lumps. The batter should be thick but still pourable.
• Rest the batter: Some batters, such as those made with flour and water, can benefit from resting for about 30 minutes before use. This allows the ingredients to hydrate properly and can result in a smoother batter.
• Adjust the thickness: If you prefer a thicker batter, you can reduce the amount of liquid or increase the amount of flour. A thicker batter may be desired for a heartier coating that can stand up to the weight of the fish.
• Avoid over-mixing: Be careful not to over-mix the batter, as this can affect its consistency and make it tough. Mix until all the ingredients are incorporated and you have a smooth batter.
• Season to taste: While a basic fish batter typically includes flour, baking powder or cornstarch, liquid, and salt, you can also experiment with additional seasonings. Just be mindful that too many spices can mask the delicate flavour of the fish.

Frying time

The frying time for fish depends on the thickness of the fillets and the temperature of the oil. It's important to preheat your deep fryer to the correct temperature before adding the fish. The ideal temperature for frying fish is between 350 and 375 degrees Fahrenheit. If the oil is too cold, the fish will absorb too much oil and become greasy. On the other hand, if the oil is too hot, the fish will burn.

When frying fish, it's best to work in batches to avoid overcrowding the fryer, which can cause the oil temperature to drop. Depending on the size of your fryer, you can fry 1-3 pieces of fish at a time. For each batch, carefully lower the battered fish into the hot oil, being careful not to splash. Fry the fish for 4-6 minutes, or until the batter is golden brown and the fish is cooked through. Use a slotted spoon or tongs to remove the fish from the oil, and place it on a plate lined with paper towels to absorb any excess oil.

For thicker fillets, you may need to increase the frying time by a minute or two to ensure that the fish is cooked all the way through. It's important to keep an eye on the fish while it's frying, as it can go from golden brown to burnt very quickly. Once the fish is done to your liking, remove it from the oil and drain any excess. Serve immediately while hot and crispy!

Some recipes recommend letting the battered fish sit in the refrigerator for an hour or even overnight before frying, as this can help the batter adhere better to the fish and result in a crispier crust. However, this is not necessary for all recipes, and you can achieve excellent results without this step by following the instructions above for frying time and temperature.

Frequently asked questions