Fried foods are coveted for their rich flavor and golden brown exterior. Creating these delicacies in a home or commercial kitchen is easy as long as you procure the proper oil and cooking vessel.
Food should be fully submerged in oil during deep frying. When using an electric or gas fryer, fill oil to the “max fill” so that the fryer baskets can be fully submerged. Generally, a deep fryer will require 9 to 16 cups of oil to have sufficient liquid to submerge a medium-sized batch of food, depending on the size of the fryer.
Because of the varying sizes of fryers and foods, there is no one size fits all answer for how much oil is needed to deep fry food. Continue reading for an extensive guide on how much oil to use for a variety of common foods.
Different Types of Deep Fryers
Deep frying is different from cooking with oil in a frying pan over the stove. All deep fryers essentially fulfill the same purpose: immerse the food in hot oil to cook it all the way through while dehydrating the outside of the food for a crispy texture.
Depending on what type of food you’d like to cook may determine what type of deep fryer you need. Below is a list of common fryers that require oil.
- Electric countertop fryer
- Commercial natural gas tube floor fryer
- Propane countertop gas fryer
- Commercial countertop pressure fryer
- Freestanding outdoor propane fryer
- Outdoor propane fryer cart
Most fryers will come with instructions for the oil level and maximum temperature. Deep fryers for commercial and home use are typically heated between 325 and 375 degrees F.
Deep Fryer Oil Chart
Displacement occurs when a solid is added to a liquid, such as oil. The mass of the food, or solid, takes up space and pushes the oil up and out to fill more of the container. Without care, the oil can overflow from adding too much food to an overfilled deep fryer.
When oil heats up and cooks food, it expands. Filling a fryer to the top will cause it to bubble over and out of the fryer, creating a kitchen hazard. This is why most fryers have a max fill line.
It’s important to have enough oil to cook food thoroughly. It’s also a bonus not to waste oil by adding an unnecessary amount. Below is a chart that details the safe recommended quantity of oil needed for common fried foods.
Food to Deep Fry | Amount of Oil Needed |
Chicken Nuggets | Fill fryer to ½ capacity |
French Fries | Fill fryer to ⅓ capacity |
Donuts | At least 2 qt oil, fryer at no more than ¾ capacity |
Eggs | At least 2 cups of oil, fryer at no more than ¾ capacity |
| Fish | Fill fryer to ½ capacity |
Pork Chops | Fill fryer to no more than ⅔ capacity |
Chips | Fill fryer to no more than ½ capacity |
Churros | Fill fryer to no more than ½ capacity |
Aside from the fried foods listed above, there are some larger foods that require specific quantities of oil. Deep-fried turkey for example is a popular Thanksgiving tradition.
How Much Oil Do You Need To Deep Fry a Turkey?
Outdoor turkey fryers are used to fry turkeys whole. Turkey fryers can range in sizes from 29 quarts to 44 quarts. Peanut or canola oil are common for turkey frying.
There are different sizes of turkeys available depending on the number of people that need to be fed. Below is a table detailing the amount of oil needed to fry small, medium, and large turkeys.
| Turkey Size (lbs) | Oil Needed to Deep Fry |
| 10 | 2 to 3 gallons |
| 11 | 2 to 3.5 gallons |
| 12 | 2.2 to 4 gallons |
| 13 | 2.4 to 4.5 gallons |
| 14 | 2.6 to 5 gallons |
| 15 | 2.8 to 5 gallons |
| 16 | 3 to 5 gallons |
| 17 | 3.2 to 5 gallons |
| 18 | 3.5 to 5 gallons |
| 19 | 3.8 to 5 gallons |
| 20 | 4.5 to 5 gallons |
| 21 | 5 to 6 gallons |
| 22 | 5 to 6 gallons |
| 23 | 6.5 to 7 gallons |
| 24 | 6.5 to 7 gallons |
If the table above does not accommodate your home setup, there is an easy way to measure how much oil you need. Place the turkey in the fryer and then fill it up with water until the turkey is submerged, measuring the amount of water added to the fryer.
Then, take the turkey and water out carefully, dry the fryer, and add as much oil as water. The turkey should be submerged so that it bobs beneath one to two inches of oil.
How Far Up Should Oil Be Filled In a Deep Fryer?
In a deep fryer, the oil should never exceed the “max fill” line. There should be enough room for the baskets and food to displace the oil already in the fryer.
If there is no “max fill” line, leave at least six inches of space between the oil and the top of the fryer’s reservoir in a commercial fryer. For a countertop fryer, fill no more than ¾ of the way with oil.
Can You Reuse Oil In a Deep Fryer?
Oil in a deep fryer can be reused. However, the quality of the oil deteriorates over time depending on the amount of foods fried in one batch and the types of food fried.
After a while, you may start to notice oil turning from a light golden yellow to a dark brown color. Frying with darker oil will make food look more done than it actually is from color contamination.
Another disadvantage to using leftover oil is that it can transfer potential allergens to the next batch. For example, frying chicken nuggets will leave traces of gluten in the oil since the breading on the chicken nugget is made with flour.
If a gluten intolerant person eats french fries cooked in that same oil, there is a risk of them ingesting gluten from the previous batch.
How Many Times Can You Reuse Oil In a Deep Fryer?
In a restaurant setting, it is common to change fryer oil every two to seven days for quality and cost efficiency. Oil can be strained off food particles that accumulate in the fryer after a day of food service so that old particles that fall off of fried foods do not attach themselves to newly fried foods.
There are many pros and cons to consider for how frequently to change oil. To read more about reusing oil in a deep fryer, we recommend reading this article.
What’s the Best Oil For Deep Frying?
The classic aroma of deep-fried foods is a result of particular fatty acids heated to high temperatures. There are three types of fatty acids: saturated fatty acids, monounsaturated fatty acids, and polyunsaturated fatty acids.
The smoke point determines at what temperature a certain oil will begin emitting smoke from its surface. Smoking occurs when the fat reaches a temperature that causes it to break down from a liquid to a gas.
The best oil for deep frying has a high smoke point and will not deteriorate or spontaneously ignite at the standard fryer temperature of 375 degrees F. Fresh refined vegetable oils can withstand up to 450 degrees F.
Different varieties of oil have different smoke points depending on their free fatty acid content. The fat is more stable and less likely to smoke at a high temperature if the oil has fewer free fatty acids. Below is a table detailing commonly used oils for deep frying and their fatty-acid content and smoke point.
| Oil | Saturated Fatty Acids | Monounsaturated Fatty Acids | Polyunsaturated Fatty Acids | Smoke Point |
| Canola Oil | 7% | 55% | 33% | 375 to 450 degrees F |
| Peanut Oil | 17% | 46% | 32% | 450 degrees F |
| Soybean Oil | 14% | 23% | 58% | 450 to 475 degrees F |
| Sunflower Oil | 13% | 24% | 59% | 450 degrees F |
Many commercial kitchens purchase pre-mixed blend oil for their deep fryers. A blend of 50/50 soybean and peanut oil is cheaper than purchasing 100% pure peanut oil. Its smoke point remains stable at 450 degrees F.
Frying foods in a blend of canola and soybean oil keeps the food from absorbing flavors carried by the oil. It also contains 0% trans fat which is ideal for people with health concerns surrounding high cholesterol or risk of heart disease.
Can You Use Oil Left In a Deep Fryer Overnight?
Restaurants may use oil that has been left out in a deep fryer overnight. However, this is not always the case, and there are certain precautions to take when doing so.
Oil can harbor hazards in the form of biological, physical, and chemical contaminants. Anaerobic oil left unrefrigerated can grow the bacteria Clostridium botulinum which is a biological contaminant.
To prevent physical contaminants such as hair, tools, and bugs from falling into the oil overnight, it’s best left covered. For example, it is common practice to cover the top of the oil reservoir with a sheet pan or lid overnight.
During rounds of cleaning, it is important to shield the oil from chemical contaminants such as sanitizers and detergents. If an exterminator sprays insecticide in the kitchen, it is also important to properly cover the oil so that the chemical does not seep into the oil and transfer to the food fried in that oil later on.
If leaving oil in a frying vessel overnight, make sure to turn off the fryer completely to let the oil cool. In a home setting, leftover oil can be stored in a clean glass jar in the freezer or refrigerator with the date of use labeled on the container.
Use or get rid of any leftover oil that has been in storage for 30 days. Rancid or “bad” oil has a sour, bitter, or stale flavor and contains carcinogens that are dangerous for the body. Never use leftover oil if it has gone rancid.