The process can be used to remove surface oil from a number of fried foods, including potato chip products, snacks, taco shells and pizzas.
General Mills said using an air flow technique meant manufacturers could remove and capture excess oil after frying in a controlled way – something that had previously been a challenge.
Usually, it said excess oil either dripped off the surface or was absorbed into the product surface during transportation to the next processing step.
Air flow chamber
General Mills detailed design elements of its air flow chamber which were important to controlled oil removal.
The snack, it explained, was placed on a moving, vibrating conveyor belt in between an inlet and outlet of air that could be configured accordingly.
Pressure inside the chamber, it said, was maintained at a level equal or less than ambient to prevent oil-laden air being transmitted outside the chamber and temperatures are kept above 100°c.
The company used two air flow types inside the chamber – laminar which flows in parallel layers and turbulent which is less orderly. “In non-scientific terms, laminar flow is ‘smooth’, while turbulent flow is ‘rough’,” General Mills wrote in its patent filing.
The company also integrated an air flow diverter element, enabling air flow to move easily around more complex shapes like rounded or v-shaped snacks.
Frito-Lay patent granted
Last year, rival snack maker Frito-Lay was granted a patent on its two-step oil removal process.
Its processing method relies on differential pressures and a vacuum centrifuge that it said drew out oil from the interior spaces of potato slices.
Frito-Lay claimed its method almost doubled oil reduction.
Source: WIPO Publication No. WO2015065465
Published: May 7 2015. Filed: November 1 2013.
“Oil Removal from Food Surface”
Authors: General Mills – D. Hunzeker