Fit to be Fried

How to choose the right oil, equipment and food for frying.

Abbie Westra, Director, Editorial, CSP

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Deep-frying foods may not require the finesse of the sauté pan, but it’s nonetheless a cooking technique fraught with hurdles. Three seemingly simple components—oil, fryer and food—must be carefully chosen and maintained. Further, trans-fat and menu-labeling legislation requires careful consideration of the health implications of fried foods, while hot oil demands proper safety precautions. Add to that daily cleaning, employee training and everevolving technology, and there’s more than meets the eye in a modest french fry.

Following are key tools and tips to help you make important decisions about your fried-foods menu. 

Fryer Terminology  

Cooking Curve: The duration for which food is held at a specific temperature, varying based on the type of food, oil absorption and desired outcome. For best results, temperatures should be maintained at 330 to 350 degrees at the beginning of the fry cycle, reduced to near 330 degrees for a short period, then elevated again to 330 to 350 degrees. Computerized fryers can adjust cook times in response to average oil temperature, and they have the ability to maintain a steady cooking curve for a consistent product.

Fry Life: The amount of time oil lasts in a deep fryer before breaking down to the point where it negatively affects food quality. Consistent fryer maintenance and cleaning practices, as well as the use of a high-quality frying oil, help increase fry life.

Sediment Zones: A more temperate, less turbulent space below the cooking area of the fryer where crumbs and other contaminants from the oil fall. Also called cold zones, these areas help improve food quality and oil longevity by keeping particles from carbonizing.

Open Pot Fryer: Fryers in which heating conductors are located outside of the frypot and feature deep sediment zones. The external heating elements make for easy cleaning and therefore longer oil life. Best for light- to medium-battered foods such as fries and prepackaged items.

Tube-Type Fryers: Heating conductors are located inside the frypot, and wide sediment-collection zones are located below the conductor tubes. Because the tubes are typically fixed, these models can be harder to clean. Best used for fresh battered or heavily breaded foods such as fresh fish and onion blossoms.

Flat-Bottom Fryers: Heat is conducted through the fryer bottom. Some models have a deep sediment zone below the heat source, and others have none—meaning sediment is exposed to the highest temperatures for a longer period of time, leading to rapid oil breakdown. Nonetheless, these fryers are easier to clean and use than open pot and tube-type fryers. Ideal for specialty products that float on top of the oil, such as fried fish, onion rings and doughnuts.

Enclosed Fryer: Automates the frying process and eliminates the need for ventilation. Food enters the machine via an entry shoot, and the employee chooses the proper temperature and time. The food is cooked and dumped into an exterior tray. The enclosed models keep staffers safe from hot oil. Best for stores where staffing and training is minimal, and where ventilation is difficult or unavailable.

Oil Choice

For such a seemingly simple food product, edible oil is a controversial part of the pantry. When Congress sought to eliminate trans fats from the food industry, oil companies had to act fast to supply food manufacturers and operators with enough trans-fat-free oils for all of the restaurant and packaged foods that take a dip in a fryer. Some of these oils had issues with oxidation— a problem those trans-fatladen hydrogenated oils had solved. So seed and oil companies are now working on a next generation of oils that are trans-fat-free and provide the stability and functionality the industry was used to with hydrogenated oils.

Examples of these next-generation oils include:

  • High-oleic canola and sunflower oils: High levels of oleic fatty acids contribute to stability without hydrogenation and keep oils from oxidation and breakdown. The increased stability leads to increased fry life, and hence lower food costs. High-oleic oils are also high in mono-unsaturated (omega-9) fat, considered good for the heart.
  • Low-linolenic soybean oils: When linolenic acid levels are too high, the oil’s stability is reduced and the oil is more prone to oxidative breakdown. Lower levels of linolenic acids increase stability, thereby improving fry life and decreasing food costs. Also, high levels of linolenic acids create a grassy, fishy or otherwise unfavorable aroma in oils, which lowered levels help offset.
  • High-oleic soybean oil:An oil currently in development is Plenish, a higholeic soybean oil that solves a negative trait that soybean oil inherently has: high levels of saturated fat. Plenish is about 20% lower in saturated-fat content than conventional soybean oil. The oil is not commercially available yet; it is being tested with some major food companies while it awaits regulatory reviews.

These newer-generation oils also come at a premium, so it’s vital to take a close look at your operation before making a purchasing decision. Don Banks, president of Edible Oil Technology, a firm that consults on the production and use of vegetable oils, recommends operators assess their fried-food volumes, the amount of downtime between batches (which puts heat stress on the oil), and their ability to test, maintain and manage oil quality shift-to-shift, day-to-day.

“If you have good fryer management, then you’ll be able to use a very wide selection of oils and still produce good product,” says Banks. On the other hand, if an operation puts a lot of heat stress on its oils, with limited addition of replenishment oil, “then I would recommend the highest-stability oil that is consistent with their operation, because the higher stability the oil, the quality of the food will stay closer to the same. It’ll still be subject to heat stress and degredation, but it would take a lot longer.”

 In the end, fry life depends greatly on the specific oil and fryer; consult with manufacturers for best practices. 

Fryer Evolution

More than cauldrons of bubbling oil, fryers are becoming increasingly advanced, with oiltemperature management systems, integrated fryer controls and automated oil-replenishment and filtration capabilities. The technology offers enhanced food quality, longer oil life, reduced labor costs and energy savings—all of which lead to better food costs.

This year, two fryers have been honored with a Kitchen Innovations award from the National Restaurant Association. The Evolution Elite from Henny Penny Corp. was honored for its new iControl, which tracks all fryer activity from oil-filtration history to daily frying stats—providing the operator with data to improve oil usage and product quality and watch for trouble areas. Last year, Henny Penny won for its thennew Evolution Elite, which enables operators to conduct as-needed oil filtering in four minutes. Enclosed-fryer manufacturer Perfect Fry Co. garnered a Kitchen Innovations award for its new Spin Fresh Centrifugal Fryer. During a final convection cooking step, the Spin Fresh spins off excess oil, providing reduced calories and improved taste. The new line will be available late in the second quarter. 

Oil Maintenance

As oil interacts with food, heat and oxygen, its composition changes. Byproducts are created, altering the characteristics of the oil and, therefore, the foods that it’s cooking. There are several steps operators can take to maintain oil quality throughout the day. For some advice on proper fryer management, CSP turned to Paul Drew, executive chef of Phillips at the Pier and Phillips Express in Atlantic City, and Arturo Paz, executive chef of Phillips Harborplace in Baltimore, both of whom fry up hundreds of pounds of shrimp, calamari, crab cakes and french fries weekly.

Fry Frozen. Slacked-out products don’t hold breading as well once they are in the fryer as frozen foods do, harming product quality and shortening oil longevity, says Paz.

Factor in Recovery Time. Ensure you’re maintaining proper oil temperatures and allowing for oil recovery time. “You’re taking a frozen product out of a freezer—it’s very, very cold and it reduces the temperature of your oil,” says Drew. The result? The batter falls off and the food absorbs more oil. French fries have a short cooking time that makes proper recovery time difficult.

Focus on Food Consistency. Paz uses molded-fiber trays to absorb the oil from just-fried products. After a few seconds on the tray, items come off consistently crispy.

Keep Oil Clean.Load and shake fry baskets away from the fryer to keep any loose food particles from falling into the oil.

Create a Stringent Oil Filtration and Replacement Protocol.Careful, frequent filtering will remove food particles and undissolved salts that normally collect in the oil during frying. If oil is contaminated by any unexpected substance or object, it should be disposed of immediately in accordance with safe handling guidelines. The fryer should also be carefully cleaned and sanitized before being used again. Above all, follow your fryer and oil manufacturers’ recommendations and instructions for frypot cleaning and oil replacement. 

Frying Green

Tips for energy-saving frying practices from Energy Star and the Food Service Technology Center (;

  • Fryers are typically idle more than 75% of the time, even in a busy operation. You can save $250 annually by cutting four hours of idle time per day (figure is for gas fryers).
  • If you have a backup fryer, turn it off when you don’t need it, and save up to $150 annually. Energy Star-qualified fryers save $120 on electricity bills annually (electric fryer), or $590 on gas bills (gas fryer). Visit for a list of Energy Star fryers.
  • A high-efficiency gas fryer costs more up front, but it uses up to 30% less energy than a standard gas fryer.
  • Have your fryer recalibrated regularly to ensure further cooking efficiencies.

Additional resources for this article include Fit Frying, The Food Service Technology Center, United Soybean Board, and CanolaInfo.

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