Sunflower oil-soybean wax oleogel: An oxidation stable alternative to traditional frying methods for doughnut

Abstract

Deep-frying changes the quality of the oil through hydrolysis, oxidation, and polymerization, which makes both positive and harmful changes in the oil and fried food items. In this study sunflower oil was combined with soybean wax to create oleogels that were assessed for their ability to reduce fat uptake and maintain oxidative stability during the deep-fat frying of doughnut samples. The oleogel was tested as a potential alternative to traditional deep-fat frying with sunflower oil for frying doughnuts. The different frying times of oleogel were examined to assess the physical properties of the oleogel. Afterward, a comparative analysis was conducted between doughnuts fried in sunflower oil and oleogel. The results showed that doughnuts fried in oleogel absorbed approximately 37.8% less oil than those fried in sunflower oil. Additionally, the doughnuts fried in oleogel had a better appearance, with a higher lightness value (L*) (87.73 ± 0.8) than those fried in oil (77.72 ± 1.35). Moreover, the redness value, (a*) of oleogel doughnuts was also lower (0.33 ± 0.25) than those fried in oil (0.37 ± 0.9). The blueness or yellowness (b*) of the doughnuts was not significantly different which was found as 1.52 and 1.54, for oleogel and oil samples, respectively. Although the viscosity values of oleogel were higher during extended frying, the lower peroxide, free fatty acid, p-Anisidine, conjugated diene, and triene values suggest that oleogel is more stable. These results will provide a significant advantage in the usage of sunflower oil-soybean wax oleogel as a frying medium with improved stability.