The selection of an appropriate edible coating and effective pretreatment before the frying process can prevent moisture loss and also reduce oil uptake during frying. As a non-thermal pretreatment, ultrasound offers a wide range of applications in frying processes, especially in reducing oil absorption. In this study, the effect of guar gum based edible coating and ultrasonic pretreatment on the quality parameters of fried potato slices (FPS) was investigated. The frying time, moisture content, oil uptake, texture hardness, surface area change, surface color parameters (lightness, redness, yellowness, and total color change), and sensory attributes were assessed after the frying process. Edible coating with guar gum and ultrasonic pretreatment significantly increased the frying time of the slices (p<0.05). Ultrasonic power (75 W or 150 W) did not have a significant impact on changing the moisture content of fried potato pieces (p>0.05). The guar gum based edible coating inhibits the oil uptake in samples by reducing water evaporation. The highest (26.36%) and lowest (10.74%) oil uptake were for the uncoated and coated-high-power-sonicated (150 W) FPS, respectively. The ultrasound pretreatment significantly decreased the hardness of fried potato pieces (p<0.05). The low and high intensity ultrasonic pretreatment (75 W and 150 W, respectively) significantly decreased the crust area change of FPS (p<0.05). The minimum redness, yellowness, and total color change indexes were for the coated and high-power sonicated (150 W) samples. The highest appearance, odor, texture, flavor, and overall acceptance were for the coated and high-power sonicated (150 W) sample.
