Everyone wants a long life, just not old age. That’s especially true for snack makers searching for ways to get the most out of their soy, palm, canola, sunflower and other cooking oils that have possibly doubled or even tripled in price due to global weather, geopolitical and supply chain challenges.
While large food manufacturers can rely on hedging to control the cost of commodities, small to midsize producers of donuts, chips and other finger-lickin’ treats often have had to eat profits, pass costs onto consumers or find other ways to fry another day.
Cutting corners, however, might not be the best idea, as tempting as it sounds.
“One of the biggest mistakes is selecting low-cost oils in an effort to improve the bottom line,” said Don Giles, snack applications, Heat and Control. “For product consistency, maintaining oil quality is a key element, of which the cooking oil turnover rate is a crucial component. Because oil is absorbed into the product, it is important that it is of a high quality for taste and product appearance and shelf life.”
Alan Craker, international sales manager for Belshaw Adamatic Bakery Group, emphasized a focus on the fundamentals such as daily filtering and cleaning of the fryer if continuous filtering is not an option.
“If there are longer breaks in production, fryer temperature should be reduced to help expand the life of the oil,” he advised. “Fryers have more accurate controls that help keep the oil at a more consistent temperature.”
Another hot tip is to ensure that the oil is not heated above the recommended temperature, noted Patricia Kennedy, president and chief executive officer, WP Bakery Group USA. For standard palm oil, for example, the temperature shouldn’t exceed 363°F (184°C) because that’s when the oil tends to crack. However, the maximum heat differs with other oils.
“In the case of exceeding the maximum oil temperature, you need to develop a process to keep below this temperature and ensure that the heating system for your fryer is gentle and accurate,” she said.
A solution for one type of fryer, Ms. Kennedy recommended, involves taking thermal oil through a heat exchanger where the large pipe surface area eliminates hot spots while ensuring accurate temperature control.
Snack makers should also avoid running their fryers below 80% of the nominal capacity, which extends the oil turnover time and results in reduced oil quality, observed Dan Luna, processing solution specialist, TNA North America.
If changeovers or unexpected downtime interrupt the process and production halts for more than 30 minutes, he suggested draining the fryer and cooling the oil before it’s pumped into the tank.
“Circulating the oil for a prolonged period, while maintaining the frying temperature at the nominal level, will unavoidably lead to air entering under the fryer hood as no steam is being created,” Mr. Luna explained. “This can lead to oil deterioration.”
Various filtering options are available from batch to continuous. Mr. Craker pointed out that batch filtering is normally used for operations that run 8 to 16 hours a day and have breaks in production. Continuous filtering, he added, is most practical in a 24-hour operation and can use a paper-style filtering system, centrifuge or other means of cleaning the oil.
Ms. Kennedy noted that some processes, such as modern, thermal heating systems with a heat exchanger, continuously pump and filter the frying oil before it’s heated to the desired temperature.
With filtering, Mr. Giles said, eliminating fines from the oil will help maintain good oil quality.
“A properly designed fryer system with the proper oil turnover rate can eliminate the need to discard oil entirely,” he explained. “This saves money and time because the oil does not need to be replaced, and the production line does not need to be interrupted to change the oil.”
Mr. Giles added that the most effective oil cleaning systems include both full-flow filtration, which captures larger particles by filtering the fryer’s oil volume once per minute, and partial-flow oil filtration, which removes smaller particles at a rate of roughly five to six times per hour.
“This helps maintain oil quality by preventing oil breakdown and ‘peppering’ fines — or tiny particles — that leave black specs on the finished product,” he said.
Heat and Control recently introduced the NIA OilSaver Filtration System, which is a partial-flow filter that uses vacuum technology to remove fines as small as 10 microns from the oil.
Mr. Giles stated this partial-flow filter can be used with a full-flow oil filtration system to preserve cooking oil quality and lengthen its shelf life. OilSaver can be added to existing systems in most cases.
Mr. Luna mentioned that new online filtration methods remove particulates left behind from sliced products, especially low-oil intake products, while the fryer is running. New offline chemical filtering can also help snack producers extend oil life with some offline oil chemical treatments eliminating oil waste altogether.
“It’s important for snack producers to evaluate their oil costs versus treatment costs to determine the best solution for them,” he said.
In addition to filtering, snack makers should keep track of the oil turnover rate, which monitors the amount of oil used during the frying process. That rate is calculated by determining the time it takes for oil usage to equal the total volume of oil in a fryer.
“The product itself plays the greatest role in determining the rate of oil consumption, so one type of fryer does not inherently consume more oil than another type,” said James Padilla, general fryer and filter applications, Heat and Control. “However, different fryer types have different total system oil volume, which will result in varying oil turnover rates. So, choosing a fryer with the lowest practical system oil volume is always important. The key is to operate the fryer at the designed production rate to ensure oil consumption is optimized.”
Overall, a faster oil turnover rate promotes good oil quality and should always be looked at closely.
“Choosing fryer systems that have a low system oil volume and highly effective frying oil filtration is very important,” Mr. Padilla said. “The low oil volume results in faster oil turnover rates, and good filtration keeps the oil cleaner, which helps maintain good oil quality. These two aspects always should be examined closely.”
When it comes to increasingly costly cooking oil, the secret to a long life involves investing in technology that prevents it from aging and following best practices that prolong the inevitable.
This article is an excerpt from the August 2022 issue of Baking & Snack. To read the entire feature on Frying, click here.