A comparison of the efficacy of radiant and immersion frying using hash brown patties as a model food matrix
Radiant frying is an alternative technique to traditional immersion frying. While enjoyed by consumers, immersion fried foods are typically high in fat. Radiant frying uses infrared energy to produce finished products with similar sensory characteristics to traditional frying, but with significantly less fat. This research compared the efficacy of radiant and immersion frying using hash brown patties as a model food matrix by measuring temperature profiles, heat flux profiles, moisture and oil contents, peak shear force, color, mottling, and crust thickness as well as executing semi-trained and untrained sensory evaluations. The FryLess 100K Radiant Fryer was used for all experimentation. ^ The heat flux profile a hash brown patty is exposed to during radiant frying was measured and the use of reflectors was shown to increase the total power by 197%. Neighboring emitters were shown to provide a 25% increase to the measured heat flux of a single emitter. Radiant fried hash brown patties had a 14.39% higher average moisture content and 52.29% lower average oil content compared to the immersion fried samples. No significant differences (P > 0.05) were found in peak shear force, L*, a*, and crust thickness. Immersion frying resulted in samples with significantly higher average b* value, indicating more yellowness, as well as less mottling and lower average core temperature compared to radiant frying. A consumer panel (n=101) found no significant difference in overall preference, purchase intent, overall liking, and flavor liking between hash browns fried using the two different techniques. Immersion fried hash brown patties scored significantly higher for appearance, color, and crispness liking, while radiant fried samples scored significantly higher for oiliness liking. Descriptors of radiant and immersion fried hash brown patties were generated by a semi-trained panel (n=7) for the appearance, aroma, flavor, and texture. It is believed that with further refinement to the radiant frying process and product formulation, radiant frying could be a suitable alternative to traditional immersion frying^
Brian E. Farkas, Purdue University, Kevin M. Keener, Purdue University.