Get to Know Your Commercial Fryer

Learn more about your commercial deep fryer with this list of terms and definitions.
Automatic Filter: A built-in system that filters a fryer's oil with very little involvement from the operator. These will typically track time or cook cycles between filter cycles, and prompt the user to initiate filtering with the push of a button when needed. Some also include oil quality testing that alerts the user when filtering is needed.
Automated Top-off: A feature available on some high-end fryer models that automatically adds oil to the frypot when the oil falls below a preset level. The oil used to top off the frypot is usually stored in a jug underneath or near the fryer.
Baffles: Metal pieces located inside burner tubes in tube-style frypots that help diffuse heat. The flame from the burner is aimed into the tube, where it flows over and around the baffles. The baffles are long pieces shaped into zig-zag-shaped folds and have holes to allow for adequate airflow.
Basket Lift: A feature typically found on high-end fryers that consists of an arm or rod that on which fryer baskets are hung. When the user starts a cooking cycle, the system lowers the baskets into the oil and they are automatically lifted out when the timer indicates cooking is done.

Batter: A wet coating for fried food, often a mixture of flour, eggs, and milk or water. When deep-fried, battered food will often sink before floating to the top of the oil, necessitating a smooth fryer vat bottom that will not allow the battered food to stick.

Battery: A series of two or more fryers sold as a single unit that share a common gas or electrical connection, and often also share a filtration system. These can be purchased in pre-made sets or custom-ordered for larger installations.
Boil-Out: The process of cleaning a fryer by way of boiling water and cleaning solution in the vat after it has been emptied of oil.

Breading: A coating used on fried or baked foods that is mostly dry. Chicken, fish, and other items are usually dredged through a milk and egg mixture before being dipped in bread crumbs and cooked. Breaded items produce more sediment than battered products.

Burner: The part of a gas fryer that produces heat to raise the temperature of the oil. These may either be around the walls of the frypot or inside it, with stainless steel tubes fitted with baffles to promote maximal heat distribution. In each design, the gas is burned to create the heat. Despite design innovations meant to make gas fryers more efficient, heat transfer is typically about 40-50 percent in these models, with the remainder of the heat vented through the flue.

Burner Tubes: These hollow cylinders are welded into tube-style frypots, allowing gas burners to distribute heat through the oil from inside the frypot. The heat from the burning gas is fired through the tubes, with baffles enabling maximal transfer of heat to the oil.
Carbonization: A term used to describe what happens to food sediment as it burns in oil, leaving behind a coal-like carbon residue. This process is due to organic material decomposing quickly at high temperatures in an environment lacking in oxygen (in this case, submerged in oil). Carbonized materials can contribute to the increased degradation of cooking oil, so cold zones are provided in many fryers for sediment to settle in without burning.

Clean-out Rod: A narrow rod with one or more bends in it meant for helping clear sediment out of a fryer's drain. Some models have a plastic handle for easier maneuvering.
Clearance: The distance required between a piece of equipment and an adjacent surface, which ensures proper air circulation where needed and also helps reduce heat transferred to nearby surfaces. For heat-emitting equipment like fryers, different clearance requirements may be specified for combustible and non-combustible surfaces. Additionally, extra clearance and a splash guard may be required between fryers and equipment with open flames, such as gas-powered ranges, to help prevent flare-ups.
Cold Zone: An area in some frypots below the burners where sediment can settle without burning. While the oil is not as hot as in the cooking area, "cold" is a bit of a misnomer, as the oil is still hot, just not hot enough to cook and burn the food that falls there.

Crumb Scoop: Designed for removing sediment from the bottom of the frypot, some scoops are wide with short handles, meant for use with flat-bottom fryers, while others are narrow with long handles, meant for scooping crumbs from open-pot cold zone areas and underneath burner tubes.

Drainboard: A shelf-like surface secured to the side of a fryer that can be used to allow excess oil to drain off cooked foods, often used for food items not cooked in baskets. Drainboards are usually slanted to direct the oil that comes off the food back into the frypot.

Drain Valve: Provides a means of draining the oil out of the frypot. Depending on the type of fryer you have, this may be visible from the front of the equipment, or it may be hidden inside the cabinet below the vat. These are equipped with handles that allow you to open and close the valve. The output pipe is usually very short to ensure it doesn’t protrude into nearby walkways, but a drain valve extension can be attached to allow oil to flow into a receptacle.
Drain Valve Extension: A curved pipe that is screwed onto the frypot's drain valve to allow oil to drain into a receptacle.

ENERGY STAR: A program developed by the EPA that sets standards for energy-efficient buildings, lighting, electronics, and equipment. Commercial fryers that have been certified by ENERGY STAR are the most energy efficient models available.

Filter Cone Holder: A conical metal basket that has arms extending from each side to allow it to be positioned over a bucket or pot. Cone-shaped filters are inserted into the cone and oil is poured into it to be filtered.

Filter Paper: Paper made to allow oil to flow through while capturing any particles in the oil that is available in flat sheets for use in oil filter systems and as cone-shaped filters that are inserted into filter cone holders.

Fish Plate: Also called fish grates and fish screens, these are flat, stainless steel grates that are submerged in the oil to keep free-floating battered products from sticking to the burners or burner tubes of the frypot.
Flavor Transfer: Describes the sharing of tastes between foods via frying oil. Strongly flavored items like fish and onions can imbue oil with a distinct flavor that can be passed to other items cooked in that oil. While regular filtering can lessen this, many operators prefer to fry these items in separate fryers or in a split-pot fryer.
Flue: A chimney-like construct at the back of the fryer where heat and fumes are directed up into the exhaust hood. These are only needed on gas fryers and some models offer flue extensions, which release the heat closer to the ventilation to reduce heat in the kitchen.

French Fry Scoop: A handled scoop that is wide on the front and tapers into a narrow chute. Fries are scooped up with the wide end, then directed through the narrow chute and into the serving containers. Scoops can have one handle, usually for use with the right hand, or can have two handles for use with either hand.

Fry Basket Divider: A metal mesh screen made to fit horizontally into a fryer basket, helping keep different types of food separate. The divider has a handle that stands straight up so it can be removed from the oil as needed.
Fry Basket Rack: Also called a fryer basket support screen or support rack, this is a stainless steel or nickel-plated metal screen that is positioned over a fryer's burners, providing the fryer baskets a place to rest when lowered into the oil. These are available in varying shapes and sizes to fit into different fryer models.

Fry Dump Station: A piece of equipment made for keeping fried food warm and crispy. These may have burners underneath a bin that holds food, or they may have warmers above the holding area instead or in addition to the underburners. Some models have a shelf made for holding food that has already been put into a box or bag. Dump stations are available in countertop and floor models, and some fryers have dump stations built in. Most models hold fried foods on grates, allowing sediment to fall out into a crumb tray below.

Fryer Basket: A steel or nickel-plated mesh or grid basket that holds food while it cooks. They are usually rectangular, but can also be square or round in shape. Fryer baskets usually have plastic handles, but some economy models have metal handles. A rectangular basket will typically have a hook on the end to allow the basket to be hung on a basket hanger or basket lift.

Fryer Brush: A long, narrow brush mounted on a long metal rod, usually with a plastic handle at the top. These brushes usually have bends at the very end, allowing users to scrub the undersides of burner tubes without having to reach underneath them, reducing the risk of burns.

Fryer Cover: A metal lid for a frypot that keeps dust and debris out of the oil and can extend the life of the oil by slowing its oxidation. Each fryer cover is made to fit a specific vat and many have notches to accommodate basket handles. Fryer covers will have one or two handles on top, which may be bare metal or have a plastic coating.
Fryer Powder: One of several substances that aid in cleaning oil and extending its life. The power is added directly to the frypot before filtering or sprinkled over the filter paper, with the dirty oil poured over it. The powder bonds with small sediment in the oil, forming larger clumps that are caught by the paper, providing more thorough cleaning. Some types of fryer powder also initiate a chemical reaction and require extended contact with the oil to be effective, so be sure to follow all manufacturer instructions.

Fryer Screen: Also known as a grate, a fryer screen is a metal grid shaped to fit the frypot. These are placed in the vat over the burners to help prevent sediment from reaching them. Fryer screens should be removed regularly and emptied to extend the time between oil filtering and frypot cleaning. Fryer screens are made to fit electric, tube, open-pot, and split-pot fryers, and some models have handles to make removing them from the oil for cleaning easier.

Frypot: Also known as the tank or vat, the frypot is where the oil in a fryer is held and where food is cooked. Frypots come in a variety of shapes, and the burners may be inside or outside them.
Grate: See fryer screen.
Heating Elements: The part of an electric fryer that produces heat in the frypot. These are usually submerged directly in the oil and are often hinged to lift out easily for cleaning. Because they allow for direct heat transfer, electric elements provide significantly more efficient operation.
High-temperature Limit: A safety feature that prevents fires by stopping the flow of gas or electricity if a fryer's oil gets too hot. A thermostatic probe is positioned in the frypot to measure the temperature of the oil and will activate when the temperature reaches that model's upper limit, which is usually between 395 and 425 degrees Fahrenheit.
Hinged Elements: See lift-out elements.

Hood: Part of a commercial ventilation system that must be installed in the kitchen. Fans in the hood work to remove grease-laden vapors and heat from the kitchen, making the area cooler and safer. Fire codes and health regulations require most fryers to be positioned under a hood, though ventless fryers have built-in ventilation and do not require a hood.

Lift-out Elements: A type of electric element that has a hinge on one end so the user can swing it up and out of the oil. This makes cleaning the elements themselves and the frypot underneath easier.
Melt Cycle: A feature that heats the frypot slowly when the unit is first started up. This puts less stress on the welded joints of the frypot and causes oil to degrade more slowly. A melt cycle allows the user to make use of solid shortening, which costs less than liquid oil.

Night Cover: See fryer cover.
Oil Capacity: The amount of oil a frypot can hold, usually given in pounds. A fryer's output per hour can be calculated by multiplying the oil capacity by 1.5 to 2. For example, if a fryer holds 20 pounds of oil, it can be expected to put out 15 to 20 pounds of food product per hour.
Pressure Fryer: These fryers apply pressure as well as heat, making them fast and efficient. Available in electric and gas, these are often preferred for cooking chicken, especially bone-in chicken.
Pressure Regulator: Moderates the flow of gas into the fryer at a rate dictated by the manufacturer.

Quick Disconnect: A type of gas connector hose coupling that allows the hose to be disconnected very quickly. This design is available with both male and female couplings and makes moving gas fryers for cleaning simple. These will cut off the flow of gas when disconnected to prevent gas leaks.
Recovery: Describes how quickly oil in the frypot will return to its set temperature after cold or frozen food is added. Many operators use recovery time as a key indicator of fryer quality, but some also value a slower recovery time, as the temporarily lower temperatures allow the inside of proteins to cook longer without burning the outside. However, if temperatures drop too low, the cooking food will end up overly greasy.
Ribbon Elements: Another name for electric elements that are located inside of the frypot. So named for their narrow, winding shape.
Safety Shut-off: See high-temperature limit.

Sediment: Small pieces that fall off of cooking food in a fryer, often pieces of breading. Food sediment can burn and carbonize, degrading the oil quickly. Cold zones allow sediment to settle in oil that is cool enough to not continue cooking it.
Shortening Disposal Unit: A piece of equipment made for removing spent oil from the frypot using either a pump or gravity. These have wheels to make transporting the oil to a collection point simple.

Skimmer: A long-handled metal utensil made for scooping out free-floating items like donuts and battered chicken. The scooping apparatus can be round or rectangular and has a metal mesh to allow oil to drain off the food.
Solid Shortening: A frying medium made of vegetable oils that have been fully or partially hydrogenated to make them solid at room temperature. These last longer and have a flavor often preferred over solid oil, but require a melt cycle to be used in a fryer.

Splash Guard: A thin, flat piece of metal mounted to one or both sides of the fryer to keep hot oil from splashing out onto the floor, wall, or other pieces of equipment. It is especially important to have one of these when a fryer is positioned next to a gas range, as oil splashing onto the burner's flame could cause dangerous flare-ups.
Split Pot: A frypot that is split into two separate sections with a wall that prevents the oil from mingling. This is often used as a means of preventing flavor transfer.

Tank: See frypot.
Vat: See frypot.
Ventless: A type of fryer that has a built-in ventilation system to remove grease-laden vapors and heat. Because fryers are required by law to be placed under a hood, ventless fryers are often used where there is no room under the current hood or installing a hood is cost-prohibitive.