Canola Oil: Deep Frying Lifespan And Best Practices

Canola oil is a popular choice for deep frying due to its neutral flavour and high smoke point. While canola oil can be reused for deep frying, several factors determine its longevity. These include the type of food being fried, the presence of food particles, and the frying temperature. Battered foods, such as onion rings, and bare foods, like French fries, leave minimal residue, allowing the oil to be reused multiple times. In contrast, breaded foods and flour-dredged items can contaminate the oil with crumbs and flour, reducing its lifespan. Additionally, the ideal frying temperature of 375 °F (190 °C) should be maintained to prevent oil absorption and greasiness. By following these guidelines and using your senses to detect signs of oil degradation, you can maximise the lifespan of canola oil in a deep fryer.

Canola oil is suitable for deep frying

However, it's important to note that canola oil is high in polyunsaturated fats, which can react with oxygen and form harmful compounds when exposed to high heat. This means that while canola oil can be used for deep frying, it may not be the healthiest option. Some healthier alternatives include coconut oil, olive oil, lard, tallow, ghee, and animal fats, which are more stable at high temperatures due to their higher saturated and monounsaturated fat content.

When deep frying with canola oil, it's important to maintain the ideal frying temperature of 375 °F (190 °C) to ensure food is cooked through without absorbing excess oil. Preheating the oil to a higher temperature of 390 °F (200 °C) is recommended to compensate for the temperature drop when cold food is added. Additionally, using a batter or bread coating can help create a protective layer that prevents oil from penetrating the food, resulting in less greasy dishes.

To extend the lifespan of canola oil, it's crucial to store it properly. Frying oil can be reused multiple times, but it should be strained and stored in a tightly sealed container in a cool, dark place or the refrigerator when not in use. However, it's important to replace the oil when it shows signs of degradation, such as loose particles, smoke at temperatures below 375 °F (190 °C), or a rancid smell.

In summary, while canola oil is suitable for deep frying due to its neutral flavour and high smoke point, it may not be the healthiest option due to its high polyunsaturated fat content. Proper storage and maintenance can extend the lifespan of canola oil, but it should be replaced when it shows signs of degradation.

Canola oil can be reused several times

When reusing canola oil, it's important to look out for signs that the oil needs to be replaced. Used canola oil should not be used if there is foam on the surface when it is hot, or if it has a strange smell, such as a fishy odour. Additionally, if the oil creates a lot of smoke at a lower temperature than usual, it may be time to replace it. The appearance of the oil can also be an indicator; if it looks dark or dirty, it's best to discard it.

The type of food being fried can also impact the lifespan of canola oil. Battered foods, such as onion rings, tend to leave fewer residues in the oil, while breaded foods like chicken cutlets can leave crumbs that break down faster. Cooking oily or fatty foods like chicken wings or bacon can also cause the oil to break down more quickly. Therefore, canola oil used for frying battered or bare foods may last longer than when used for breaded or flour-dredged foods.

To prolong the lifespan of canola oil, it is recommended to use a thermometer to monitor the oil temperature and avoid overheating. It is also important to keep the oil clean by using a fine-mesh strainer to remove any debris or particles that may fall into the oil during frying. By following these tips, you can safely reuse canola oil several times and maintain its quality for deep frying.

Store canola oil in a cool, dark place

Storing canola oil in a cool, dark place is essential for maintaining its quality and freshness. By keeping it away from direct sunlight and heat sources, you can prevent oxidation and rancidity, which can lead to off-flavours and odours. A cool, dark cupboard or pantry can be a suitable storage location for the short term, protecting the oil from light and air exposure.

However, for long-term storage, it is advisable to choose a very cool and dry spot in the kitchen, preferably with temperatures between 57°F and 70°F (13.9°C and 21.1°C). Lower temperatures slow down the oxidation process, helping to preserve the oil's freshness for longer. To further protect the oil from light, you can transfer it to a dark glass bottle or a dark or opaque container.

Remember to seal the bottle tightly after each use to minimise air exposure and extend the oil's shelf life. Additionally, avoid storing canola oil near the stove or other heat-emitting appliances, as this can affect its quality and freshness.

Factors that can ruin canola oil

Canola oil is a great choice for deep frying due to its high smoke point, neutral flavour, and health benefits. However, there are several factors that can ruin canola oil, shortening its lifespan and reducing its effectiveness. Here are some key factors that can impact the quality and longevity of canola oil in a deep fryer:

High Temperatures

While canola oil has a high smoke point, which means it can withstand high temperatures without smoking or burning, excessive heat can still negatively affect the oil. Oil that is too hot will burn the exterior of the food before the interior has a chance to cook. This can result in an unevenly cooked product with an undesirable texture and taste.

Low Temperatures

On the other hand, if the oil temperature is too low, it can seep into the food, resulting in greasy and soggy food. The ideal frying temperature for canola oil is between 350°F and 375°F. Preheating the oil to a higher temperature, such as 390°F, ensures that the oil returns to its ideal temperature once cold food is added.

Contamination

Contamination can occur when frying moist food or overcrowding the fryer. Moisture can cause the oil to splatter and can also make the food greasy. Overcrowding the fryer can cause the temperature of the oil to drop, affecting the cooking process and the quality of the food. It is important to fry food in small batches and ensure that the food is dry and coated with a thin layer of batter or breading.

Reusing Oil

Canola oil can be reused multiple times, but it is important to follow proper filtering and storage techniques. After each use, the oil should be strained to remove any food particles, and it must be stored in a cool, dark place. Reusing canola oil too many times without proper filtration and storage can cause it to become rancid.

Salt

Adding salt to food before frying can draw moisture to the surface, causing splattering when the food is added to the hot oil. Salt also lowers the smoke point of the oil, making it more susceptible to burning at lower temperatures. It is recommended to avoid adding salt until after the frying process is complete.

Food Particles and Sediment

Over time, loose particles can accumulate as sediment at the bottom of the storage container or become suspended in the oil. This can affect the quality and taste of the oil, as well as the food being fried. Regular filtering and proper storage can help extend the lifespan of the oil and delay the buildup of sediment.

Rancidity

Canola oil can go rancid over time, developing an unpleasant or "off" smell. This can be caused by improper storage, exposure to light and heat, or reusing the oil too many times without proper filtration. It is important to store canola oil in an airtight container in a cool, dark place to prevent rancidity.

How to increase the lifespan of canola oil

Canola oil is a popular choice for deep frying due to its neutral flavour and high smoke point. The oil can be reused for frying multiple times, but its lifespan depends on how it is stored and used. To increase the lifespan of canola oil in a deep fryer, follow these steps:

Maintain the Ideal Frying Temperature:

Keep the oil temperature between 350°F and 375°F (176-190°C). Oil that is too hot will burn the exterior of the food before the interior is cooked. On the other hand, oil that is not hot enough will result in greasy, soggy food.

Use a Thermometer:

By using a thermometer, you can ensure that the oil temperature stays within the ideal range. This will help prevent the oil from burning or breaking down prematurely.

Preheat the Oil:

Before adding food, preheat the oil to 390°F (200°C). This higher temperature ensures that the oil returns to the ideal frying temperature once cold food is introduced.

Avoid Overcrowding the Deep Fryer:

Cook in small batches to avoid overcrowding the fryer, as this will lower the oil's temperature. This will help maintain the ideal frying temperature and reduce the chance of the oil becoming too hot or too cold.

Use a Batter or Bread Coating:

Coating foods with a batter or breading creates a protective layer that prevents oil from penetrating the food, reducing greasiness.

Avoid Adding Salt Before Frying:

Salt draws moisture to the surface of food, which can cause splattering when added to hot oil. Additionally, salt lowers the smoke point of the oil, increasing the likelihood of burning.

Remove Excess Moisture:

When frying frozen foods, remove any excess ice to avoid hot oil splatter. Moisture can lower the oil's temperature and affect its quality.

Store the Oil Properly:

After use, allow the oil to cool, then strain it through paper towels, coffee filters, or cheesecloth into its original container or a clean glass jar. Store the oil in a tightly sealed container in a cool, dark place or in the refrigerator. Proper storage will help prevent oxidation and rancidity, extending the oil's lifespan.

Monitor the Oil's Condition:

Check the oil for any signs of spoilage, such as a rancid smell or off taste. Canola oil should have a neutral, almost imperceptible smell and a clean taste. If the oil shows signs of cloudiness, sediment, or mould, it has gone bad.

Frequently asked questions