Effect of basil seed gum coating and ultrasound pretreatment on frying time, oil uptake, hardness, color indexes, and sensory properties of potato slices

Abstract

Fried food products have low oil content with improved nutritional quality, higher crispiness, and better sensory attributes. Edible coatings can decrease the excessive oil uptake in deep-fat fried food products. Furthermore, ultrasound treatment before frying process decreased oil uptake of food products. So, in this study, the impact of gum edible coating and ultrasonic pretreatment (at two different power levels of 75 and 150 W) on the frying time of potato slices, and moisture percent, oil uptake, texture hardness, surface area change, color parameters (lightness, redness, yellowness, and total color change), and sensory attributes of fried potato slices were examined. Edible coating with basil seed gum (BSG) and ultrasonic pretreatment significantly increased the frying time of the slices (p < 0.05). The average moisture content of the fried slices changed from 49.48 % to 60.55 %, and was further increased by edible coating and ultrasonic treatment. The highest (26.92 %) and lowest (14.56 %) oil uptake were for the uncoated and coated-sonicated (150 W) fried potato slices, respectively. The ultrasound pretreatment significantly increased the hardness of fried potato slices (p < 0.05). The low and high intensity ultrasonic pretreatment (75 W and 150 W, respectively) significantly decreased the crust area change of fried potato slices (p < 0.05). The average lightness index of the fried samples changed from 63.30 to 71.58, and increased with increasing ultrasonic power. The minimum redness, yellowness, and total color change indexes were for the coated and high-power sonicated (150 W) samples, respectively. The highest appearance, odor, texture, flavor, and overall acceptance were for the coated and high-power sonicated (150 W) sample.

Keywords: Edible coating; Overall acceptance; Surface area; Texture hardness; Total color change.

Graphical abstract

Fig. 1

Preparation processes of potato slices and basil seed gum dispersion, edible coating and ultrasonic treatment, and samples frying process.

Fig. 2

Effect of edible coating and ultrasound pretreatment (US) on frying time of potato slices. Different letters indicated statistically significant differences between different treatments (p < 0.05).

Fig. 3

Effect of edible coating and ultrasound pretreatment (US) on moisture content of fried potato slices. Different letters indicated statistically significant differences between different treatments (p < 0.05).

Fig. 4

Effect of edible coating and ultrasound pretreatment (US) on oil uptake of fried potato slices. Different letters indicated statistically significant differences between different treatments (p < 0.05).

Fig. 5

Effect of edible coating and ultrasound pretreatment (US) on texture hardness of fried potato slices. Different letters indicated statistically significant differences between different treatments (p < 0.05).

Fig. 6

Effect of edible coating and ultrasound pretreatment (US) on surface area change of fried potato slices. Different letters indicated statistically significant differences between different treatments (p < 0.05).

Fig. 7

Effect of edible coating and ultrasound pretreatment (US) on crust color indexes (lightness, redness, yellowness, and total color change) of fried potato slices. Different letters indicated statistically significant differences between different treatments (p < 0.05).