What a difference an oil change makes
Laurie Gorton, Baking & Snack
Sometime this spring, we’ll learn the fate of the oils we now use for frying foods. If the balance tips away from partially hydrogenated oils (PHOs), as it could, bakers and snack food producers will need to reevaluate their frying equipment as well as their ingredients.
In November, the Food and Drug Administration (FDA) gave notice that PHOs would no longer be “generally recognized as safe,” or GRAS. FDA cited the trans fat content of PHOs as the reason for proposing this change. Trans fats, formed during hydrogenation of vegetable oils, have been linked to increased risk of coronary heart disease.
Partial hydrogenation stabilizes vegetable oils by raising their resistance to oxidative breakdown. Seeking alternatives to hydrogenation, shortening suppliers turned to palm oil and to high-oleic, low-linolenic oils pressed from soybean, sunflower and canola. (See “Fry with Stability” in September Baking & Snack, Page 91.) Available now, these new-generation frying shortenings do the job but usually at higher costs than PHOs and commodity oils.
Equipment ramifications play out not in the fryer but in oil filtering and temperature control systems. “The type of oil used does not really affect the frying modules,” explained Ken Weekes, international sales manager and product manager, roll lines, WP Kemper, WP Bakery Group. “The difference would be in frying time or filter size.”
As noted by Don Giles, director of sales, processing equipment, Heat and Control, Inc., “More attention must be paid to oil turnover rate and oil filtration to assure good oil quality and high-quality finished products.”
Frying shortenings, including the new trans-fat-free styles, harden on cooling. “Remnants of shortening could sometimes be left to solidify in the pump mechanism, making pump seizure a possibility,” explained Irene Kimmerly, vice-president, sales, Belshaw Adamatic Bakery Group. For this reason, the company made some design changes in its filtration systems. It added all-over heat to its filtering systems to keep shortenings fluid throughout the operation, including the pump.
Filtering systems have gone continuous, especially for larger fryers, noted Patricia Kennedy, president, WP Bakery Group USA. “The introduction of continuous filter systems, some with automatic ejection of larger particulates, increases the oil life,” she said. “This means oil replenishment happens less often, and the product quality remains high throughout the lifetime of the oil.
“Better quality oils have a higher smoking point, meaning they should last longer between changes,” Ms. Kennedy added. “That’s a good thing, but if you use more expensive oils, then looking after them to maximize their usable life makes even more sense.”