5 Frying Oil Questions Answered by a Food Scientist

5 Frying Oil Questions Answered by a Food Scientist


Rick Stier is a consulting food scientist experienced with frying oil and frying oil programs. He holds degrees in food science from Rutgers University and the University of California at Davis. Mr. Stier helps foodservice operators develop safety, quality, and sanitation programs with the goals of increasing profits for the establishment. He is a contributing editor for Food Engineering.

Mr. Stier sat down with the Filtercorp team to answer a few important frying oil questions about increasing and maintaining the quality of a commercial foodservice frying program, which always begins with the quality of the oil itself.


Filtercorp: What does food science have to do with frying oil?

Stier: Food science is the science of food, which includes food chemistry, food microbiology, food processing, product development, sensory science engineering, and many other disciplines. A food scientist with an interest in frying oil could study the chemistries associated with oil degradation, or a product development scientist might be interested in optimizing frying parameters to produce a certain product. A food engineer could end up working on new fryers or any of the other equipment involved with bringing the food to the fryer and taking it away. Frying oil, how it’s used, and how it is produced could keep many different persons from food science busy.


Filtercorp: How long have you been working with oil?

Stier: I began working with fats, oils, and frying in 1988, when I joined a small contract laboratory whose mission was to develop and sell test kits to be used for monitoring fry oil quality and safety. Of course, when the intent is to sell such products to a specific industry, it is imperative that one understands that industry.


Filtercorp: Why are there cold zones and hot zones in a deep vat fryer? 

Stier: There shouldn’t be. A well-designed fryer should maintain uniform temperature and have the ability to recover quickly. By recover, we mean the ability to return to operating temperatures after food is dropped into the fryer vat. This is especially important in foodservice fryers and kettle fryers used to produce kettle-style chips. In fact, part of validating the performance of industrial fryers is to monitor temperatures across the length and width of the unit to demonstrate there is uniform heating throughout the system.


Filtercorp: What is the difference between zero (non) trans fat oil and other typical frying oils?

Stier: Before discussing the differences in frying oils with no trans fatty acids and other frying oils, we should probably tell people about trans fatty acids. According to the American Heart Association, there are two broad types of trans fats found in foods: naturally occurring and artificial trans fats.

Naturally occurring trans fats are produced in the gut of some animals, and foods made from these animals (e.g., milk and meat products) may contain small quantities of these fats. Artificial trans fats (or trans fatty acids) are created in an industrial process that adds hydrogen to liquid vegetable oils to make them more solid. The industrial process that produces trans fats is called hydrogenation. Hydrogenation hardens fats and helps to stabilize them by reducing the potential for oxidation. Many fats used for deep fat frying were partially hydrogenated to extend their useable life.

Because of the potential health concerns associated with trans fatty acids, fryer operators are looking for frying fats with zero trans fats. This has led to the utilization of frying fats that are not hydrogenated. However, to enhance stability and fry life of the oil, processors may use oils that are blended from two or more sources such as canola, soybean. or sunflower.


Filtercorp: Why is filtration a vital part of oil maintenance?

Stier: Filtration has been acknowledged as an essential element for maintaining the quality of frying oils for over fifty years. Canadian scientist, Dr. C.J. Robertson, published two papers in 1967 and 1968 that highlighted five elements for quality frying. One of these was that fryer operators “regularly filter” their frying oils.

Dr. Glen Jacobsen from The Campbell’s Soup Company reiterated the importance of Dr. Robertson’s recommendations in a short course organized by the Institute of Food Technologists at the 1990 Annual Meeting of the Institute of Food Technologists. Jacobsen’s presentation was published in Food Technology in 1991. He emphasized the importance of removing solids from oils as they could darken oil, impede heat transfer, contribute to off flavors in foods, and ruin the appearance of the fried foods. Today, we know that filtration does much more, especially if a company adopts an active filtration process or treats the oil.

The First Step to Any Oil Filtration Program

Select a frying oil treatment system that stands above the rest. The right filter pads should absorb more than just the enemies of oil, they should also absorb costs so you don’t have to.

Take the first steps and download our free Guide to SuperSorb® CarbonPads, and see how your frying oil program can benefit.



* Would you like to hear more from Rick Stier? Read part two of the interview.

By | 2018-04-26T18:30:51+00:00 June 24th, 2015|Categories: Frying Oil, SuperSorb Carbon Pads|Tags: , , , |Comments Off on 5 Frying Oil Questions Answered by a Food Scientist

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