How To Properly Store And Reuse Deep Fryer Oil

Deep-frying produces a flavor like nothing else, but it's a messy, dangerous, and expensive process. One way to reduce the cost is to reuse the oil, and many people swear by it. However, reusing oil can pose health concerns, and it's important to take steps to do it safely.

The chemical composition of oil starts to change at 375°F (190°C), and it's this change that makes reheated oil unhealthy. To reduce the risk of this happening, choose your oil wisely, strain it after each use, and store it correctly.

When reusing oil, it's best to avoid oils that are high in polyunsaturated fats, such as grapeseed or sunflower oil, as these are unstable when heated. Instead, opt for oils with a high smoke point (400°F/200°C or higher), such as olive oil, canola oil, peanut oil, or vegetable oil.

After frying, turn off the heat and allow the oil to cool completely. Then, strain the oil through a fine-mesh sieve lined with cheesecloth or coffee filters to catch any fine particles. Transfer the strained oil into a clean, airtight container and store it in a cool, dry place, or in the refrigerator if you're not planning on using it soon.

Used oil can be reused anywhere from two to eight times, depending on the type of oil, what you're frying, and how well you've strained it. However, it's important to pay attention to the oil and look out for any changes. If the oil becomes dark or dirty, smokes before reaching frying temperature, foams at the top, or develops a rancid or musty smell, it's time to discard it.

Reusing deep fryer oil

Yes, you can reuse deep fryer oil. However, there are some important steps to follow to ensure you do it safely.

How to Reuse Deep Fryer Oil

Firstly, it is important to start with the right oil and equipment. Use an oil with a high smoking point (400°F+) such as peanut oil, canola oil, or vegetable oil. Electric fryers are useful as they regulate the oil temperature and shut down if it gets too hot. If using a stovetop, a thermometer is needed to gauge the temperature of the oil.

When frying, carefully maintain the oil's temperature to prolong its life. When oil surpasses its smoke point, its fats start to break down, releasing a substance called acrolein, which gives burnt food a bitter taste.

Once you have finished frying, allow the oil to cool completely. Then, filter the oil to remove any impurities such as crumbs or sediment. Never filter hot oil as this can cause burns. Drape a few layers of cheesecloth or coffee filters in a fine-mesh strainer over your storage container and pour the oil through.

Each time oil is reused, it gets more and more destabilized until it decomposes. Used oil will have a thicker consistency and a darker colour. It will also develop an acrid aroma. If the oil looks cloudy or foamy, it's time to throw it away. Even if the oil looks and smells fine, it is recommended to reuse frying oil no more than three times before discarding it. Do not reuse frying oil that has been stored for more than 1-2 months.

Storing Reused Deep Fryer Oil

Keep in mind that frying oil will take on the flavour of the food cooked in it. Therefore, it is recommended to label used oils to prevent any unfortunate flavour overlaps. For best results, store the oil in an airtight container in the refrigerator. Over time, used oil can oxidize if exposed to too much light or heat.

Discarding Reused Deep Fryer Oil

Do not pour oil down the drain as it will get stuck in pipes and cause plumbing problems. Instead, place the oil in a closed vessel and chill it, then discard the solidified oil with your regular trash. Alternatively, find a local disposal center that accepts used cooking oil.

Storing deep fryer oil

• Allow the oil to cool completely before storing. Never attempt to filter or store hot oil, as it can cause serious burns if you slip or splash.
• Once the oil has cooled, strain it through a fine-mesh sieve or cheesecloth to remove any crumbs or sediment. This step is crucial if you fried breaded or battered food, as these tend to leave behind debris that can burn the next time you use the oil.
• Store the strained oil in an airtight container, such as a glass jar or the original container the oil came in.
• Label the container with the date, what the oil was used for, and the number of times it has been used. This will help you keep track of how many times the oil has been reused.
• Store the container in a cool, dry, dark place, such as a cabinet or pantry. Do not store it near the oven, fridge, or microwave, as the heat can cause the oil to degrade faster.
• If you are not planning on using the oil again soon, it is best to store it in the refrigerator or freezer. Used oil can oxidize if exposed to too much light or heat, so keeping it cold will extend its shelf life.
• Reused oil takes on the flavour of the food cooked in it, so keep oils used for different types of food separate. For example, don't use oil that was used for frying fish to fry doughnuts.
• Each time you reuse oil, it gets more destabilized until it decomposes. Look out for signs of spoilage, such as a dark colour, thick texture, rancid smell, food residue, or a bubbly appearance. If you notice any of these, it's time to discard the oil.

Straining deep fryer oil

Step 1: Allow the Oil to Cool

Before straining, it is important to let the oil cool down completely. This is a crucial safety measure, as oil burns can be dangerous. Allow the oil to cool to room temperature.

Step 2: Prepare the Straining Setup

There are several methods and tools you can use to strain deep fryer oil. Here are some options:

• Fine-mesh sieve or strainer: Place a fine-mesh sieve or strainer over a bowl or container to catch the strained oil. You can line the sieve with a filter for finer straining.
• Filters: Paper coffee filters, cheesecloth, or flour sack towels can be used as filters. Place the chosen filter inside the sieve or strainer.
• Funnel: If you're straining the oil back into its original container or a narrow-necked bottle, you may need a funnel to avoid messes.

Step 3: Strain the Oil

Once your straining setup is ready, slowly pour the cooled oil into the filter. Stop pouring when you reach the last bit of oil that contains deep-fry debris, such as bits of flour or batter. The oil will slowly pass through the filter and into the container below.

Step 4: Store the Strained Oil

After straining, pour the oil into a clean, airtight container. You can reuse the oil's original container or opt for a glass jar. Label the container with the date, the type of oil, and the number of times it has been used. Store it in a cool, dry, and dark place, such as a cupboard away from the oven or fridge.

By following these steps, you can effectively strain and store deep fryer oil for reuse. Just remember to pay attention to the oil's quality and discard it if it develops an unpleasant odour, dark appearance, or other signs of degradation.

Discarding deep fryer oil

So, what are your options for discarding deep fryer oil? Here are some methods:

• Solidify it, then trash it: Use a product like FryAway to solidify the oil into a block that can be thrown away.
• Transfer to a closed container, then toss it: Pour the oil into a sealable disposable container (like the original bottle) and throw it away.
• Recycle it: Check if there are any recycling drop-offs near you that accept used cooking oil, or contact local services.
• Freeze it: Pour the cooled oil into a plastic container, freeze it, and then dispose of the block of oil.

Remember to always handle the oil with care and dispose of it responsibly to avoid any plumbing or environmental issues.

Health concerns of reusing deep fryer oil

Reusing deep fryer oil can be economical and environmentally friendly, but it's important to be aware of the potential health risks. Here are some key points to consider regarding the health concerns of reusing deep fryer oil:

Health Risks of Reusing Deep Fryer Oil:

• Formation of Harmful Compounds: Reheating oil can lead to the formation of harmful compounds such as aldehydes, including acrolein, which is toxic and potentially carcinogenic. Aldehydes are produced when oil is reheated, and their concentration increases with each reuse. Consuming these compounds has been linked to an increased risk of cancer.
• Increased Inflammation: Reusing deep fryer oil can lead to increased inflammation in the body. This is due to the formation of free radicals, which are bad-for-you atoms that can cause cell damage. Inflammation can reduce your body's immunity, making you more susceptible to infections and diseases.
• Cholesterol and Heart Disease: Consuming food fried in rancid oil can increase the levels of bad cholesterol in the body. This, in turn, can elevate the risk of developing heart diseases, stroke, and chest pain. The real culprit behind these issues is often not the fried food itself but the degraded oil used for frying.
• Acidity and Stomach Issues: Reheated oil can cause acidity and stomachaches. This is a common complaint among people who consume deep-fried food from roadside vendors, as they often reuse oil multiple times without changing it.
• Bacterial Contamination: Reusing deep fryer oil can create an environment conducive to bacterial growth and contamination. This increases the risk of food poisoning and other health issues.
• Particulate Matter: If the oil is not properly filtered and cleaned, it can contain particulate matter and impurities that are harmful to human health. These particles can be left behind by fried foods, especially breaded items, and can burn and negatively impact the oil's quality.
• Oxidation and Free Radical Formation: Reused oil can undergo oxidation, leading to the formation of free radicals. These free radicals can cause cell damage and contribute to inflammation in the body.

Best Practices to Mitigate Health Risks:

• Regular Filtering: To extend the life of deep fryer oil and reduce health risks, it is crucial to filter the oil regularly. Use a high-quality filter to remove impurities and breakdown products that accumulate with each use.
• Proper Storage: Store the oil in a cool, dark place to prevent degradation and contamination. Keep it away from direct sunlight, heat sources, dust, and moisture.
• Temperature Control: Avoid overheating the oil, as higher temperatures accelerate its degradation. Use a thermometer to monitor the oil's temperature and avoid reaching its smoke point.
• Oil Type: Choose the right oil for deep frying. Some oils, like peanut and avocado oil, are more stable and can be reused more times than others.
• Food Type: The type of food fried also matters. Breaded foods, for example, tend to leave more crumbs and particles in the oil, shortening its lifespan.
• Change Oil Frequently: To minimize health risks, change the deep fryer oil frequently. For breaded foods, change the oil after 2-4 uses, while for non-breaded foods, change it after 6-8 uses.

Frequently asked questions