Oil Fryer Systems: Features and Applications

Chapter 1: What is an Oil Fryer System?

An oil fryer system involves heating, cooking, and drying food by immersing it in hot oil. During this process, heat is transferred to the food, enhancing its taste and texture. Oil absorption occurs at different phases, initially on the surface, with some removed through vapors. The amount of oil retained in fried food varies according to the food's shape and the specific oil removal methods employed in the oil fryer system.

Oil fryers are primarily categorized into continuous and batch systems. Batch fryers are ideal for small-scale production and niche products, where oil is brought to frying temperatures for cooking small amounts of food items at a time. On the other hand, continuous oil fryer systems are designed for high-volume production, where food is introduced at one end and comes out at the opposite end. Various strategies are applied to ensure the product is evenly and consistently processed within a continuous oil fryer system.

Chapter 2: What are Batch Oil Fryer Systems and How Do They Work?

Oil fryer systems are essential equipment in commercial and industrial food processing, and are primarily divided into two general categories: batch oil fryer systems and continuous fryer systems. These commercial frying systems break down further by their methods of power supply—most commonly electric fryers or gas fryers—and by construction type. Batch-style fryers are typically compact, manually operated, and are ideal for small-volume food production, while continuous fryers are engineered for high-capacity environments and demand significantly more energy, footprint, and setup. Understanding the differences and benefits of each style is critical for food manufacturers, restaurant owners, and catering operations seeking to optimize cooking efficiency, product consistency, and operational costs.

A vital element in maximizing the performance and lifecycle of any industrial oil fryer is its oil filtration system. Proper cooking oil filtration not only reduces operating costs by extending oil life, but also ensures superior food quality and greater equipment efficiency. Cooking oil in commercial fryers degrades with each cycle, affected by the amount and weight of food processed. To maintain the ideal fry quality, operators should monitor the oil turnover rate—a calculation based on usage volume and frequency. Routine oil filtration and replenishment of fresh oil are recommended to achieve optimal taste, food safety, and equipment longevity. High-performance cooking oil filter systems are especially important in fast-paced kitchens, large-scale snack production, and food manufacturing plants.

Batch oil fryer systems are engineered to cook food products in comparatively small batches, allowing for greater control over the frying process. Standard features of commercial batch fryers include removable fry baskets or racks for easy loading and unloading, precision temperature control, integrated or modular oil filtering systems, and efficient draining mechanisms. Batch fryers are available in a diverse array of designs, from compact countertop fryers for limited spaces to robust floor models for high-demand operations. The advanced filtration options for batch oil fryers often feature built-in filtration systems or the flexibility to pair with external mobile oil filter units, maximizing productivity and minimizing downtime.

One of the most significant advantages of batch oil frying systems is their energy efficiency and reduced oil consumption compared to larger continuous systems. These fryers offer improved control, as food is prepared for precisely timed intervals at a consistent and uniform temperature, promoting both high-quality output and lower operating costs. Batch fryers also excel in product versatility, ease of operation, and safety, making them a top choice for food preparation across snack foods, specialty products, quick-service restaurants, and institutional kitchens. Their adaptability makes batch fryers a favorite among chefs and food technologists focused on quality and flavor consistency for a wide variety of fried products.

A key subcategory within batch oil fryer design relates to heat transfer methodology: direct heating and indirect heating. With the direct heating method, the heat source comes into direct contact with the frying oil, commonly found in rectangular and circular commercial fryers, resulting in faster temperature response. Indirect heating, on the other hand, utilizes a heat exchanger that separates the heat source from the oil, thereby reducing oil breakdown and substantially increasing the operational life of the cooking oil—a critical factor in industrial-scale operations where oil replacement costs and waste reduction are important.

Open Vat Batch Fryer System

Open vat batch fryers are a widely used type of industrial fryer and are recognizable by their large, open vats. Similar in concept to residential deep fryers but on a far larger scale, these units enable food baskets to be lowered directly into the heated oil. Open vat fryers accommodate medium to large volumes and are valued for their rapid cooking times, minimal oil filtering cycles, and straightforward cleaning procedures. Both gas-fired and electric open vat fryers are available, allowing flexibility based on operational requirements.

Advanced open vat systems are equipped with computerized temperature controls that can quickly detect drops in oil temperature—such as when a new batch of food is introduced—and automatically signal the heating element to restore optimal frying temperatures, ensuring consistent product quality. Many open vat fryers feature multiple baskets for high-throughput cooking and stainless steel construction to comply with stringent food safety and sanitation standards required by health regulators and certification agencies.

Additional features often include particle screens to capture food debris, further protecting oil quality and simplifying maintenance. Open vat batch fryers are the go-to choice for restaurants, catering kitchens, and food processing lines requiring reliable performance, easy maintenance, and compliance with the latest food hygiene standards.

Tube Batch Oil Fryer System

Tube batch oil fryers are a specialized form of vat fryer, popular in commercial kitchens and food factories, known for their efficient gas heating technology. Heat is applied via tubes located at the vat's bottom, distributing warmth uniformly throughout the oil for consistent cooking performance and exceptional energy efficiency. Notably, tube fryers have a well-designed cold zone situated beneath the heating tubes, where food particles and sediment collect, preventing oil contamination and prolonging the useful life of cooking oil—a crucial feature for operations that prioritize cost reduction and quality control.

Construction details such as welded burner tubes and precision baffles enhance direct heat transfer and rapid recovery rates, making tube batch fryers a preferred solution for busy foodservice environments and large-scale snack manufacturing. The cold zone's impact on sedimentation reduces frequent oil filtration intervals, while the design maximizes oil yield and product quality. These features make tube batch oil fryers an optimal choice for businesses seeking both durability and efficiency in food frying processes.

Flat Bottom Batch Oil Fryer System

Flat bottom batch fryers utilize heating elements located underneath the fry pot, transforming the entire base into an efficient heat transfer surface. However, due to the absence of a cold zone, food fragments and sediment continue to cook and burn, requiring frequent oil filtration and generally limiting these fryers' applications to low-volume, specialty products such as tortilla chips, tempura, and other delicate snacks.

Operators benefit from a wide, unobstructed cooking area, as heating elements are external to the oil vat. This arrangement is ideal for preparing large, flat products or items that need even heat exposure. While flat bottom fryers are relatively high-maintenance due to increased cleaning frequency, their expansive cooking surface and precise temperature control make them well-suited for boutique food manufacturers and commercial kitchens producing artisan fried foods.

Open Pot Batch Oil Fryer System

Open pot batch oil fryers feature exterior heating elements, strategically positioned along the pot's rounded bottom but outside the main cooking area. This engineering creates a small cold zone at the base of the pot, below the heating elements, which helps trap sediments and minimizes oil degradation for products with lower particle output. Open pot fryers are easier to clean due to their accessible interiors and convenient drainage systems, reducing downtime and facilitating quick batch turnover.

With a design optimized for oil savings and ample space to accommodate larger batch sizes, open pot fryers are well-suited for high-volume, low-sediment foods and are commonly found in quick-serve restaurant kitchens and cafeterias. However, the limited cold zone restricts their use for products that generate significant sediment or breading. Their versatility and ergonomic configuration make open pot batch oil fryers a smart investment for efficient food production and streamlined maintenance.

Ribbon Element Oil Fryer System

Ribbon element oil fryers merge the benefits of tube and flat bottom fryers by featuring a shallow vat and a ribbon-shaped electrical heating element beneath the oil. This innovative design achieves fast, uniform heating and rapid recovery—qualities highly valued in both food manufacturing and commercial restaurant operations. Ribbon fryers often have expanded fry pot widths, supporting higher batch volumes and enabling efficient cooking for products prone to flotation or clustering.

Powered exclusively by electricity, ribbon element batch fryers deliver quick heat-up times, reduced energy consumption, and straightforward maintenance due to the uncomplicated layout of the heating elements. These fryers are especially prevalent in high-output environments, such as snack food factories, commissaries, and specialty food kitchens, where speed, efficiency, and product consistency are top priorities.

The five types of batch oil fryer systems described above represent just a selection of the many available fryer technologies. Businesses today can choose from a wide spectrum of commercial batch fryers, with custom-engineered solutions available to address unique production requirements. Regardless of the batch fryer type, core features remain consistent: an oil vat or fry pot, a robust heating mechanism (electric or gas-powered), and advanced drain and filtration systems that ensure lasting performance.

When selecting a batch oil fryer system, consider key factors such as production volume, food type, available footprint, energy source, oil filtration needs, safety standards, and ease of cleaning. Partnering with reputable fryer manufacturers for customized solutions and ongoing technical support can further enhance your food processing operation, improve fry quality, and drive greater operational efficiency and profitability. To learn more about commercial oil fryer options, manufacturers, and buying advice, explore our in-depth fryer system resources.

Chapter 3: What are Continuous Oil Fryer Systems?

In contrast to batch oil fryer systems, continuous oil fryer systems are large industrial fryers that cook and fry food continuously with exceptional efficiency. They are a necessary part of large-scale food production and are used by fast food restaurants, snack manufacturing companies, and corporate commercial food producers. Continuous oil fryer systems use a complex filtration system in order to save money and ensure the quality of fried food products.

Conveyor Belt System

The feeding apparatus for a continuous oil fryer system is a metal conveyor belt that carries the food products to the oil bath. Metal conveyor belts for the food industry are made of galvanized steel, carbon steel, mild steel, or stainless steel. The alloys that are chosen are sufficiently resilient to be able to withstand the over 600°F (315.6°C) temperatures produced during the cooking process. In addition to their heat resistance, the materials have to meet the food handling requirements of the Food and Drug Administration (FDA). Metal conveyor belts prevent slippage, maintain their tightness, can endure substantial weight, and are exceptionally reliable.

Food products are loaded on one end of the conveyor from another conveying system or manually and are placed evenly over the surface of the conveyor belt. Continuous oil fryer system conveyor belts are constantly in motion as food products are loaded. The loaded belt moves forward and down into the oil bath where the food is cooked.

A second conveyor belt runs above the feed conveyor belt to prevent food materials from floating in the oil bath. The success of the cooking process is dependent on the even speed of the conveyor belts to ensure the food remains immersed for the required cooking time.

Oil Bath

The oil bath is the central part of a continuous oil fryer system. It is the part of the fryer where the food is cooked by being immersed in hot cooking oil. For the cooking process to be successful, the oil is kept at 350°F to 375°F (175°C to 190°C). The height of the conveyor belt is adjustable to allow for the frying of all types of foods. The oil in the oil bath is constantly being filtered by being sent to an oil filter system that quickly filters the oil and returns it to the oil bath.

Cooking

The food placed on the conveyor is moved along to the oil bath that contains heated oil designed to rapidly cook the food. The method of cooking is referred to as immersion since the food is immersed in the hot oil until it is completely cooked. The hot oil in the oil bath boils off the water in the food, which evaporates quickly. The speed of the process causes the formation of a crispy layer that seals in the flavor and moisture in the food. The result of the process is an enjoyable texture with a crispy exterior and tender interior.

Cooling

At the completion of the cooking process, the food passes through a cooling zone to lower its temperature. The function of the cooling zone is to ensure the food is safe for handling and to prevent the food from overcooking. As with the loading process, when the food exits the fryer, it has to be ready to be handled for packaging or transfer to another process. It is for this reason that cooling zones are continually monitored and controlled to ensure production efficiency.

Continuous Oil Fryer System Filters

A necessary part of continuous oil fryer systems is their filtration system, which filters the oil to remove minute particles that can foul the oil and ruin the flavor of the food. Filtration systems can be built into continuous oil fryer systems and be part of their mechanism or be a self-contained unit that has the oil fed from the fryer. The process of fryer oil filters includes a constant flow of oil from the oil bath to the filter equipment and back to the fryer. It is a cost saving, economical, and efficient method for ensuring food quality.

Continuous fryer oil filter systems remove micron (µ) sized fines and impurities using a continuously operating filtering system. Fryer oil that contains contaminants is delivered by an automatic oil flow system to a large machine that uses conveyor driven moving filter paper. As fryer oil flows by gravity through the filter paper, impurities, fines, and other matter is captured. The cleaned fryer oil moves through a circulation system back to fryers for reuse.

As the filter paper automatically removes fines and impurities, it becomes loaded and is automatically advanced such that unclean fryer oil can be filtered by a clean portion of the filtering system. Paper that has been loaded with fines and impurities is removed from the continuous fryer oil filter system and disposed of. The rolls of filter paper come in a variety of porosities and can easily be changed to fit the needs of different types of fryer oil or filtering requirements.

When the fryer oil filter paper rolls are loaded into a continuous fryer oil filter system, the rolls are placed over a conveyor belt with a rod and woven metal format, which holds the paper in place as contaminated oil moves through the filter paper. As with most metal conveyors, the rods and weaving are made of steel in order to endure the heat and chemical properties of the oil.

This particular oil filtering method is one of many types of oil filtering systems which vary by system design, type of fryer, mobility, method of filtering, and several other factors. Many continuous oil fryer systems have filters as part of their structure for fasting filtering and greater efficiency.

Monitoring and Control

A continuous oil fryer system is a piece of production equipment that prepares food and has the same control requirements as other forms of industrial devices. As any chef can tell you, close temperature control is the key to the success of food preparation. Whether food is being prepared in a small batch fryer or a large voluminous continuous oil fryer, the success of the process is dependent on the ability to set the proper temperature, ensure that it is maintained, and continually oversee the process.

The size of continuous oil fryer systems necessitates the use of automatic controls that monitor the temperature of the oil and adjust the temperature. This aspect of the process needs to be automated since human oversight would not be able to react swiftly enough. Additionally, the control system monitors the cooking time to ensure that the food is immersed for the correct amount of time.

Unlike batch oil fryers, which have small panel controls, continuous oil fryers can have programmable logic controllers (PLC) that have the appearance of a computer screen. They make it possible to monitor, program, and control every aspect of the cooking process. The screen visuals vary between manufacturers with all types providing configurations that are easy to access and read.

During the frying process, workers have to monitor several chemical factors to ensure quality and success. The most important element that must be monitored is the quality of the cooking oil and the filtration system. The automated aspects of continuous oil fryer systems make it possible to oversee every aspect of the cooking process from the feeding of food materials to their completed form.

Chapter 4: What are the Different Types of Fryer Oil Filters?

The types of fryer oil filters are divided into manual, mechanical, and types of filtering methods. The determination of the type of fryer oil filter is dependent on the size of an operation and the quantity of fryer oil used. Small, mom and pop kitchens can filter their fryer oil manually since they normally have a single fryer that uses a small limited amount of oil. Large, fried food producers with continuous oil fryers require technologically advanced fryers that use a high volume of fryer oil.

Regardless of the size of an organization, the filtering of fryer oil is a necessity, cost saving, and environmentally responsible. Unlike fryer oil that is used for home cooking, organizations that use frying oils to produce their products purchase fryer oil in bulk, which can cost from $36 a container up to over $100 a container depending on how many pounds of frying oil is purchased. Being able to reuse frying oil, by filtering and cleaning it, can help a company realize substantial savings.

Continuous Fryer Oil Filter System

Continuous fryer oil filter systems are a high-capacity filtering system that is similar to the continuous fryer oil filter system. The continuous fryer oil filter treatment method has a complex set of steps that is used with high volume fryer oil filtering. The system is very similar to an industrial process and is designed for filtering fryer oil from industrial cooking and kitchens. The goal of the process is to remove free fatty acids (FFA), fines, and other impurities.

The structure of a batch fryer oil filter system includes a pressure filter, a mix tank, feed pump, and FFA powder. The system is designed for extremely high capacity and high-volume filtering. The process begins with hot fryer oil being sent from the fryer to the mix tank where it is exposed to FFA powder, which absorbs the free fatty acids. With the fatty acids removed, the fryer oil moves to the pressure filter chamber where 1 µ solid particles in the fryer oil are trapped and removed by the filter in the upper chamber of the pressure filter. The clean oil moves from the pressure filter tank to a clean fryer oil tank from which it is sent back to the fryers. Once the mix tank is refilled, the process is repeated.

Portable Fryer Oil Filter System

Portable fryer oil filter systems are a high-performance fryer oil filter solution that is light enough to be used in any sized kitchen. They are available in several forms from hand held versions to ones that are on wheels. Portable fryer oil filter systems have a rotor that is similar to larger fryer oil filter devices and filtering mesh that is made of various types of filtering materials.

The different sizes of portable fryer oil filter systems make them adaptable for any size kitchen and frying application. Portable fryer oil systems are used with stand alone gas fryers, cooking centers, and pressure fryers. The key to any type of fryer oil filter system is the rate at which it filters fryer oil. Although portable fryer oil filter systems do not have the capacity of larger more complex filtering systems, they are capable of filtering fryer oil in minutes, which makes them ideal for a fast-paced cooking environment.

Paperless Fryer Oil Filter Systems

A common form of fryer oil filter system is a paperless system that uses layers of stainless steel to remove fine and impurities as small as 100 µ. They are a cost saving type of fryer oil filter system that efficiently cleans oil during the frying process. Paperless fryer oil filter systems have to be frequently cleaned using a dishwasher or scrubbing in hot water with dish soap.

The use of paperless oil filter systems is a cost cutting method that saves on the purchase of paper filters. They can be built into a fryer or come as part of a portable fryer oil filter system.

Built-in Fryer Oil Filter System

An efficient and high-quality method for fryer oil filtration is having the fryer oil filter system built-in to a fryer. Built-in fryer oil filtration systems are available for all forms of fryers. The filter system is connected to the fryer by a drain at the bottom of the fryer. The filtering process involves pulling a lever to drain the oil from the fryer into the filtering drawer and pulling a lever to open the return valve and activate the pump that returns the fryer oil to the fryer vat.

When the drain at the bottom of the fryer is opened, fryer oil passes through a drawer that contains a filter screen and filter envelope that catch residue, fines, and sediment that darken the fryer oil. The pump in the system returns the cleaned fryer oil to the fryer vat. Once the fryer oil has been returned to the vat, the frying process can be resumed. The large manifold of the system allows for fast draining. The filter system prevents pump clogs and allows for smooth movement of fryer oil.

One of the dangers of working in large kitchens is the handling of fryer oil. The use of a built-in system enhances the safety of the workplace and protects workers. The fewer times that fryer oil is handled increases safety and provides for a smooth and efficient frying process.

Portable Fryer Oil Filters on Wheels

Portable fryer oil filters on casters or wheels come in several forms with some having four wheels while others have only two wheels. In addition to the variations in wheels, there are differences in how they filter, the type of filter, the amount of power they require, vertical or horizontal orientation, and how many pounds of fryer oil they can process. Although there are similarities between manufacturers, each manufacturer has their own proprietary fryer oil filtering process.

The casters on portable fryer oil wheel filters make it easy to move the filter and position it for use with a lift off filter pan for easy cleaning or replacement of the filter. The flexibility of portable fryer oil wheel filters makes it possible to filter any type of fryer from counter top ones to floor models with or without drains. A differentiating factor for portable fryer oil wheel filters is their capacity, which can vary from 50 lbs. and 55 lbs. up to over 100 lbs. (22.67 kg and 25 kg up to over 45.36 kg).

The operation of a portable fryer oil filter on wheels includes placing the mobile fryer oil filter next to the fryer and draining the oil in the fryer into the portable fryer oil wheel filter’s crumb pan located above its filter, which can be a paper filter or metal mesh filter. Once the oil has been filtered, it is pumped from the portable fryer oil filter on wheels back through a hose and wand into the fryer.

Fryer Oil Filters Capacity

Part of the selection process for determining the right fryer oil filter for an operation, restaurant, or kitchen is knowing the required capacity for efficient fryer oil filtering, which is dependent on how often fried foods are required. More frequent frying requires the use of a fryer oil filter with a capacity well over 100 lbs. while less frequent frying can make use of a fryer oil filter that is less than 100 lbs.

• 40 to 80 Pound Fryer Oil Filters – Fryer oil filters with a 40 to 80 lb. (18 kg to 36kg) capacity are used with drain type fryers. They are compact, which makes them ideal for small kitchens and small operations. To comply with health requirements, smaller fryer oil filters are made of stainless steel with hoses, pumps, and motors that are able to withstand high temperatures. Small fryer oil filters are easy to assemble and operate. Regardless of their small size, they work quickly and efficiently with a sturdy hose assembly and easy access to the filter and crumb pan.

  

  
  

• 130 to 210 Pounds Fryer Oil Filters – The choices for high capacity 130 to 210 pounds (59 kg to 95 kg) fryer oil filters include extremely high-capacity fryer oil filters that function like large production machines. The varieties of fryer oil filters with high capacity include large continuous fryer oil filters and extremely high-capacity batch fryer oil filters that process several hundred pounds of fryer oil and large portable fryer oil filters that function like smaller fryer oil filters but with a higher capacity.

  Higher capacity fryer oil filters tend to be more complex than small portable fryer oil filters and require oversight and monitoring. In many cases, they process fryer oil faster and more efficiently and return oil to storage tanks. This type of fryer oil filter involves several steps with each step planned and programmed into the system.

The fryer oil filtering methods described above are a small and general description of the many different fryer oil filtering methods that are available from manufacturers who work with their clients to find fryer oil filter solutions that perfectly fit the client’s needs. The fryer oil filtering process is a valuable tool for lowering costs, improving fried products, and increasing efficiency. Working closely with manufacturers and distributors, restaurants, kitchens, and food producers are able to find fryer oil filtering processes that fit their fryers and the needs of their workers.

Oil Fryer System Filter Process

There are several factors that define and characterize the fryer oil filter process. In many cases, the method of filtering, manual or electric, is the initial parameter that determines how fryer oil is filtered. In all cases, the goal of fryer oil filtering is to clean, purify, and prepare fryer oil for frying high quality foods.

In general, fryer oil filtering is a passive process, active process, or a combination of active and passive with the passive process involving the use of a filter while the active process involves the use of chemicals. In either case, the end goal is to remove contaminants, impurities, fines, and other matter from fryer oil.

The process of fryer oil filtering is an essential part of food preparation since its effects influence several aspects of food preparation. The foundational principles upon which fryer oil is filtered are cost savings and quality. It is very obvious that changing fryer oil after each time it is used is inefficient and expensive since fryer oil is one of the most expensive costs of an industrial kitchen.

The quality of prepared food and its taste is what keeps customers coming back, which is a foundational principle of running any business. Used and unclean fryer oil produces off flavors and is dirty and contaminated, a combination of factors that lowers the quality of food. Fryer oil filters ensure exceptional quality, high performance, and customer satisfaction.

The conceptual framework in regard to quality frying is built on six elements, each of which refers to proper care and maintenance of frying equipment with the final two elements being removal of contaminating materials from fryer oil and proper filtration. Of the six basic ideas, the proper and efficient filtering of fryer oil yields the greatest benefits and rewards. Passive filtration and active filtration are the general forms of fryer oil filtration.

Passive Filtration

Passive filtration is defined as a mechanical process where fryer oil is passed through a filter made of paper, fabric, or metal screen. The passive process is able to remove particulate matter as small as 2 mm, 4 mm, or 50 µ. Various forms of mechanical filters have the potential of filtering particles lower than 1 µ.

The passive filtering process can be completed using one of the various types of fryer oil mechanisms or by simply pouring fryer oil from the fryer, by hand, through a filter into a bucket or barrel. Passive filtration is completed frequently on a regular schedule, which is determined by how much is being cooked and how often.

The steps for passive filtration involve removing fryer oil from the fryer through its drain valve from which the fryer oil empties into the fryer oil filter device. During the process, the fryer is off. The fryer oil unloads into the filtering mechanism, which can take several shapes and forms and is dependent on the size and type of kitchen. Draining of the oil is the first of other steps that are necessary for the filtering process with each step designed to ensure the oil and fryer are cleaned of impurities.

Active Filtration

The active filtration process is referred to as fryer oil treatments and is a complex and intricate system for removing particulate matter and oil soluble matter. Active filtration involves the use of powders, impregnated paper or pads, and paper coated with active powder. The process for active filtration reduces oil impurities physically and chemically while removing suspended materials in fryer oil.

Fryer oil filtering is a method for repurposing and reusing fryer oil. It does not return fryer oil to its original condition since initiating frying permanently damages fryer oil, a process that cannot be reversed. The use of active and passive treatments and filters slows the degradation of fryer oil, makes it usable, and extends fryer oil’s useful life.

Chapter 5: What Are the Different Fuel Types for Oil Fryer Systems?

The choice of fuel or power for an oil fryer system is dependent on a few factors beginning with the availability of fuel types in a company’s area. The two basic types of fuel for oil fryer systems are electricity and gas that are contracted with local energy providers. A third type of fuel that can serve as an alternative to the common fuels is propane.

Natural Gas

Natural gas tends to be the first choice for a fuel source for oil fryer systems since it puts out high amounts of heat (BTUs) that is easily absorbed by the oil by direct or indirect heat from the natural gas. The wide use of natural gas is due to how quickly and efficiently it heats the oil to the needed cooking temperature. In addition, it maintains the temperature throughout the cooking process with exceptional consistency.

A restriction on the use of natural gas as a fuel source is access to a hardline since it is not portable. In many instances, buildings will have multiple electrical outlets but no gas connections. Working with utility companies and natural gas providers, it is possible to examine alternative methods for getting natural gas service.

Continuous oil fryer systems depend on natural gas as their heat source since natural gas is less expensive than electricity and heats up rapidly. All high volume food production facilities that use continuous fryers are hardlined to natural gas lines.

Electricity

Electricity is universally available and easily accessible. It is normally used for batch oil fryers with low capacity. Electricity is the most versatile of the fuel choices due to its wide availability. Of the various methods used for oil fryer systems, electricity is the least efficient since it takes the longest to heat cooking oil and has long recovery times at temperature drops. Electricity is a highly efficient fuel source and does not produce any pollutants. The restrictions on its use are in reference to the amount of oil to be heated with 30 lbs. or more of cooking oil needing a more powerful fuel source such as natural gas.

Liquid Propane

Propane has the same advantages as natural gas with the added advantage of being portable to make it universally available. It is the main source of fuel for oil fryer systems that are located in remote rural areas that do not have access to natural gas. Manufacturers provide conversion kits for clients to convert their natural gas oil fryer to a propane gas fryer.

The negative aspect of propane is its high cost, which is far higher than natural gas. Part of the high cost can be balanced against the easy availability of propane and its flexibility. Since it provides the same speed, heat, and efficiency as natural gas, it is an excellent alternative.

Fuel Supply Types

The fuel supply types align with the different types of oil fryers, since the fuel supply type, in some cases, determines the type of fryer. The heat from the fuel is supplied directly or indirectly depending on the design of the fryer where the direct method includes direct contact with the oil while the indirect method provides heat to the oil through heat transfer or heat exchange.

• Open Pot - With open pot fuel supply, the heating elements are on the outside of the fryer and supply heat through heat transfer.
• Flat Bottom - Flat bottom heating elements are under the bottom of the fryer pot and supply heat to cooking oil through heat transfer.
• Tube and Baffles - Tube and baffles are submerged in the fryer pot at its bottom and make direct contact with the oil.
• Ribbon Elements - Ribbon elements are used in electric oil fryers and are curled electric elements that use the heat transfer method.

Conclusion

• Oil turnover is a critical part of the success of any oil fryer. The rate of oil turnover is determined by the amount of oil in the system and the rate at which it is removed through frying. With a more frequent turnover rate, products are more consistent and have a better shelf life.
• The three power sources of fuel for oil fryer systems are propane, electricity and natural gas, which are applied directly or indirectly depending on the design of the oil fryer.
• Oil fryer systems are used by the food industry to produce pre cooked foods, snacks, and meals and can contain up to 5000 gal (18927 L) of cooking oil and reach temperatures of 670°F (354.4°C).
• Part of the popularity of oil fryer systems is due to the flavor and texture the process adds to food products.
• There is a wide assortment of oil fryer systems with all versions and types being batch type oil fryers or continuous oil fryers. These two general categories divide into multiple oil fryers with different designs, heat sources, and cooking methods.